Humans are not apex predators

[RonO]

There is a paper that I haven't read because I'd have to pay to see it,
but summaries of the paper indicate that the authors contend that humans
are not apex predators based on their diet. Probably not a good way to
define apex predator because it only means that we eat so many different
things that we have the ability to eat the planet bare before we go
extinct. Carnivores are self regulating. When they eat their prey to
low population levels their own population levels crash. This doesn't
apply to an apex predator like humans who just find something else to
eat and can take multiple species to extinction without slowing down much.

http://www.pnas.org/content/early/2013/11/27/1305827110

Apparently we have the diet of an anchovy, and not an apex predator.
Maybe they will start calling humans Alpha Apex Omnivores. We eat the
other apex predators and just about anything else. What can you call a
species that eats vegemite, and make expensive beverages from the poop
of wild cats.

Ron Okimoto

[Richard Norman]

I think we went through this once before. According to the ecological
definition, we are not apex predators. Whether you think that is not
a good way to define it doesn't change its use in ecology.

Sadly, your attitude seems to be sort of a peevish reaction to
discovering that we are not the end-all and be-all of life. It is
like the reaction of those bothered by the fact that we are apes. Why
should it be necessary for us to be "the" apex predator just because
we are terribly selfish bullies in our behavior within the ecosystem?

By the way, if you want the full text, just email me and I will email
it back to you. Remove the two underscores in my listed address.

[jillery]

On Fri, 06 Dec 2013 07:41:31 -0600, RonO <roki...@cox.net> wrote:

Australians?

[J. J. Lodder]

RonO <roki...@cox.net> wrote:

> There is a paper that I haven't read because I'd have to pay to see it,
> but summaries of the paper indicate that the authors contend that humans
> are not apex predators based on their diet. Probably not a good way to
> define apex predator because it only means that we eat so many different
> things that we have the ability to eat the planet bare before we go
> extinct. Carnivores are self regulating. When they eat their prey to
> low population levels their own population levels crash. This doesn't
> apply to an apex predator like humans who just find something else to
> eat and can take multiple species to extinction without slowing down much.
>
> http://www.pnas.org/content/early/2013/11/27/1305827110
>
> Apparently we have the diet of an anchovy, and not an apex predator.
> Maybe they will start calling humans Alpha Apex Omnivores. We eat the
> other apex predators and just about anything else.

Of course not.
We just exterminate them,

Jan

[Burkhard]

Only if they don't hide on top of staircases. Tricky things, them staircases

[William Morse]

Sadly, currently we are the end-all and be-all of most of the megafauna
on earth. We are exterminating much of it. That turns out to have
profound impacts on ecosystems. And we don't have any idea what those
impacts are.

[jonathan]

"Richard Norman" <r_s_n...@comcast.net> wrote in message
news:qlp3a9d3t5fhlm644...@4ax.com...

> On Fri, 06 Dec 2013 07:41:31 -0600, RonO <roki...@cox.net> wrote:
>
>>There is a paper that I haven't read because I'd have to pay to see it,
>>but summaries of the paper indicate that the authors contend that humans
>>are not apex predators based on their diet. Probably not a good way to
>>define apex predator because it only means that we eat so many different
>>things that we have the ability to eat the planet bare before we go
>>extinct. Carnivores are self regulating. When they eat their prey to
>>low population levels their own population levels crash. This doesn't
>>apply to an apex predator like humans who just find something else to
>>eat and can take multiple species to extinction without slowing down much.
>>
>>http://www.pnas.org/content/early/2013/11/27/1305827110
>>
>>Apparently we have the diet of an anchovy, and not an apex predator.
>>Maybe they will start calling humans Alpha Apex Omnivores. We eat the
>>other apex predators and just about anything else. What can you call a
>>species that eats vegemite, and make expensive beverages from the poop
>>of wild cats.
>>
>
> I think we went through this once before. According to the ecological
> definition, we are not apex predators. Whether you think that is not
> a good way to define it doesn't change its use in ecology.
>
> Sadly, your attitude seems to be sort of a peevish reaction to
> discovering that we are not the end-all and be-all of life. It is
> like the reaction of those bothered by the fact that we are apes.

Speak for yourself

> Why
> should it be necessary for us to be "the" apex predator just because
> we are terribly selfish bullies in our behavior within the ecosystem?
>

Bullies, don't you mean saviors?

The Earth usually goes into a long cold murderous
ice-age for a good hundred thousand years at a time.
With life getting these short windows where it can
bloom for a bit. But due to humans, the long ice-age
that should be showing up any day now, probably won't
happen.

[Jimbo]

Yeah. Instead we're getting, along with the warming, ocean
acidification, loss of coral reefs and decline of reef communities,
the decline of both marine and terrestrial apex predators with
associated disruptions of ecosystems.

Jellyfish, which are tolerant of acidic and low oxygen conditions, may
be taking over the oceans. If they become the ecean's primary apex
predators they may serve to stabilize future oceanic ecosystems, but
they won't be the ecosystems we know and depend on.

And there's the distinct possibility that we're creating conditions
that could precipitate another extinction event comparable to the
Permian-Triassic event when up to 96% of all marine species and 70% of
terrestrial vertebrate species became extinct.

<http://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event>

If this is global warming saving the earth, maybe an ice-age would be
better.

[Walter Bushell]

In article <l7sk6d$sq3$1...@dont-email.me>, RonO <roki...@cox.net>
wrote:

> What can you call a
> species that eats vegemite, and make expensive beverages from the poop
> of wild cats.

s/./?/

What kind of question is that, rhetorical?

Homer the sap.

--
Gambling with Other People's Money is the meth of the fiscal industry.
me -- in the spirit of Karl and Groucho Marx

[RonO]

Thanks, but I don't need the full text. You seem to be missing the
point that minimizing our impact on nature in this way is stupid. You
can't define away what humans can do on the basis of something as
unimportant as our overall diet. We can destroy the population of any
other apex predator on a whim, not just by going out and hunting them to
extinction, but we clear cut whole forests. Too many bunnies jumping
around and we can introduce a plague that decimates the population. We
don't have to eat giants like whales and elephants, we just have to make
oil and corsets from their carcasses, or make nice looking carvings from
their tusks.

The people that are concentrating on trying to place humans into our
ecology using their stupid definitions are basically just lying to
themselves. Reality should be what they deal with. What do humans
actually do and what we are capable of is what should be the issue.

I was driving with a colleague a couple of weeks ago and she noted how
large the crow flocks are getting, and it was only a couple hundred
crows. In the US we used to have a bounty on crows, they used to flock
in the millions, but with diesel fuel and dynamite you could kill
hundreds of thousands at one time, and our Ag and Forestry service did
just that. Even when the large flocks were decimated we maintained a
bounty on individual crows so that it would be economical to keep
shooting them. We changed their life style and we nearly drove them to
extinction. If they start to become a pest again (do any children know
why those stuffed humanoid forms in fields were called scarecrows?) we
will reduce their numbers again. If they weren't so smart crows would
likely have gone the way of the dodo. Most people never ate a crow,
they were just a pest. We clear cut forests for wood and land to grow
soybeans and corn on industrial farms to feed domestic animals, so that
we can eat them. Just check out Brazil, US investors are funding 30,000
acre soybean farms that used to be virgin forest. Defining away what we
do doesn't change reality.

Ron Okimoto

[Walter Bushell]

In article <qlp3a9d3t5fhlm644...@4ax.com>,

Richard Norman <r_s_n...@comcast.net> wrote:

> Sadly, your attitude seems to be sort of a peevish reaction to
> discovering that we are not the end-all and be-all of life. It is
> like the reaction of those bothered by the fact that we are apes. Why
> should it be necessary for us to be "the" apex predator just because
> we are terribly selfish bullies in our behavior within the ecosystem?

It's not a species level thing, its every animal for itself wherein
sometimes cooperation furthers individual interest. Every other
species would exhibit the same behavior, if they could and, of course,
their is a lot of fights over territory or right to breed, usually
among males.

[Walter Bushell]

In article <l7u95...@news1.newsguy.com>,

William Morse <wdNOSP...@verizon.net> wrote:

>
> Sadly, currently we are the end-all and be-all of most of the megafauna
> on earth. We are exterminating much of it. That turns out to have
> profound impacts on ecosystems. And we don't have any idea what those
> impacts are.

In broad detail we do, disaster for us.

[eridanus]

El s�bado, 7 de diciembre de 2013 12:58:55 UTC, Jimbo escribi�:

the Triassic extinction was also caused by humans? These humans are very naughty people. They are of the skin of devil.

Eridanus

[eridanus]

El s�bado, 7 de diciembre de 2013 14:12:45 UTC, Walter Bushell escribi�:

of course, wild animals are doing delayed abortions. They need to kill
their competitors even if they are of the same species. I had watched a
few videos of wildlife.

Eridanus

[Richard Norman]

The subject is not at all whether humans are destroying the ecosystem.
And the paper is not at all an apologetic for that destruction. The
simple fact is that the human diet in no way shape or form resembles
the diet of an apex predator. Because humans are guilty of some truly
grievous faults you seem to argue that nobody should pay any attention
to any other subject because that is just another way of minimizing or
justifying those faults.

[Jimbo]

The Permian-Triassic extinction may have been initiated by global
warming caused by CO2 released by massive Siberian volcanic eruptions.
The volcanic warming then brought about Arctic methane release which
kicked into motion a positive feedback cycle. Methane is a very
powerful greenhouse gas, and this combined CO2 plus CH4 greenhouse
effect caused earth's temperatures to spike.

<http://en.wikipedia.org/wiki/Permian%E2%80%93Triassic_extinction_event#Volcanism>

<http://en.wikipedia.org/wiki/Arctic_methane_release>

Although there's no direct evidence of huge methane releases at the
end of the Permian, but various other types of data, including
carbon-isotope fingerprints support it. The two-stage theory accounts
better for a wide range of evidence than do any previous theories. It
ties together lines of evidence that had been separate.

<http://www.newscientist.com/article/dn2088-methane-prime-suspect-for-greatest-mass-extinction.html#.UqNP1OLJeUk>

[Jimbo]

It seems to me that some human populations function as apex predators
but that other populations don't. We don't behave as proper species
are supposed to behave. We're hard to categorize.

[Nick Roberts]

In message <onh6a9p4l901u8qml...@4ax.com>
Richard Norman <r_s_n...@comcast.net> wrote:

[Snip]

> The subject is not at all whether humans are destroying the ecosystem.
> And the paper is not at all an apologetic for that destruction. The
> simple fact is that the human diet in no way shape or form resembles
> the diet of an apex predator.

I've not had any training in ecology, but it struck me while reading
this thread that pre-agriculture humans may indeed be apex predators.
Would this be accurate?

If so, humans may be in the unique position of being an ex
apex predator, not because a different species got better at predation,
but for social reasons.

--
Nick Roberts tigger @ orpheusinternet.co.uk

Hanlon's Razor: Never attribute to malice that which
can be adequately explained by stupidity.

[Arkalen]

On 07/12/13 18:01, Nick Roberts wrote:
> In message <onh6a9p4l901u8qml...@4ax.com>
> Richard Norman <r_s_n...@comcast.net> wrote:
>
> [Snip]
>
>> The subject is not at all whether humans are destroying the ecosystem.
>> And the paper is not at all an apologetic for that destruction. The
>> simple fact is that the human diet in no way shape or form resembles
>> the diet of an apex predator.
>
> I've not had any training in ecology, but it struck me while reading
> this thread that pre-agriculture humans may indeed be apex predators.
> Would this be accurate?

Insofar as the article says we're more like pigs and anchovies than apex
predators, I think the answer would be "no". Most pre-agriculture humans
also had varied diets including fruit, seeds, roots etc as well as meat,
and this relative omnivory is the reason we aren't apex predators (cf
the sentence in the abstract, "This value has increased with time,
consistent with the global trend toward diets higher in meat.")

This might be different in environments like the Arctic, or most of
non-tropical areas during the Ice Age.

[Jimbo]

On Sat, 07 Dec 2013 18:01:46 GMT, Nick Roberts
<tig...@orpheusinternet.co.uk> wrote:

>In message <onh6a9p4l901u8qml...@4ax.com>
> Richard Norman <r_s_n...@comcast.net> wrote:
>
>[Snip]
>
>> The subject is not at all whether humans are destroying the ecosystem.
>> And the paper is not at all an apologetic for that destruction. The
>> simple fact is that the human diet in no way shape or form resembles
>> the diet of an apex predator.
>
>I've not had any training in ecology, but it struck me while reading
>this thread that pre-agriculture humans may indeed be apex predators.
>Would this be accurate?

That's how it seems to me. If omnivorous brown bears can be
categorized as apex predators, I don't see why Eskimos, or various
cattle herders wouldn't be also.

http://en.wikipedia.org/wiki/Apex_predator

The only basic difference I see is that non-human apex predators tend
to stabilize their ecosystems while humans often destabilize ours.
Newly introduced predators can be destabilizing, but eventually a new
ecosystem dynamic develops around them. Humans can just go on and on
destabilizing ecosystems.

>If so, humans may be in the unique position of being an ex
>apex predator, not because a different species got better at predation,
>but for social reasons.

Yes. Social reasons that are tied up with the creation of new ways of
life. The main difference between humans and other species is that
different human populations can develop and culturally pass on to the
next generation entirely new ways of interacting with the environment.
Some of us can continue as apex predators even after other populations
have developed a different way of life. That's why our patterns of
environmental interaction can't really be encompassed by any of the
standard ecological categories. We may just be reshaped Pliocene apes,
but we are also, in terms of our patterns of ecological interactions,
fundamentally different from any other species that has ever existed.

[Richard Norman]

Arkalen is right, a really major reason we are not apex predators is
because a major portion of our diet is plants. Another major reason
is that there are other predators in the world who prey on humans,
especially pre-agriculture humans.

[Arkalen]

So basically you think words in ecology should mean what you think they
should mean, and not what they actually mean to ecologists. That's...
familiar.

Trophic levels don't include impact on the environment; if they did
ants, poisonous plants or invasive species of anything would have very
different trophic levels than what they do. And said level would be a
much more nebulously-defined, hard-to-measure concept, making it much
less scientifically useful.

I originally though you might have a point insofar as we kill animals
for their hides or their oil; while we aren't *eating* them,
ecologically speaking it looks like predation to me. We are actively
killing animals for our direct benefit.

But then I remembered what trophic levels are actually about, which is
the transfers of energy through the ecosystem. The concept being that
energy is captured from the sun and stored by primary producers, and
then each successive act of predation captures only a fraction of the
energy contained in the food source. An organism's trophic level in that
context, i.e. where the energy for its metabolism and carbon for its
tissues come from, i.o.w. what it eats (not what it kills or otherwise
impacts), tells you what fraction of the Sun's energy it has access to.
So defining trophic levels as anything other than diets is nonsensical,
not until humans become battery powered.

It's also bizarre that you talk about the article "minimizing our impact
on nature" when its title includes the phrase "Eating up the world's
food web". The abstract makes it clear they are presenting the
calculation of humans' trophic level as a synthetic tool to study human
diet on a sociological level. It seems you're just objecting to the
sentence saying that humans "cannot be considered apex predators", but
as you point out that just means we eat everything and no specific
shortage can constrain our growth, so it implies a greater impact on the
environment, not a lesser one. Why you think the article would suggest
anything different is a mystery to me.

[Jimbo]

But Brown bears, with the possible exception of the polar bear
subspecies, are also omnivores. Are the apex predators or not? Well,
no other predators prey on them, except for humans. Paleolithic
Europeans apparently had the formidable cave bears as at least an
occasional item in their diet. Of course the bears no doubt also dined
sometimes on humans. Were they co-mutual apex predators? I don't think
our own ecological patterns can be adequately encompassed within the
standard scheme of categorization.

[Arkalen]

On 07/12/13 20:01, Jimbo wrote:
> On Sat, 07 Dec 2013 18:01:46 GMT, Nick Roberts
> <tig...@orpheusinternet.co.uk> wrote:
>
>> In message <onh6a9p4l901u8qml...@4ax.com>
>> Richard Norman <r_s_n...@comcast.net> wrote:
>>
>> [Snip]
>>
>>> The subject is not at all whether humans are destroying the ecosystem.
>>> And the paper is not at all an apologetic for that destruction. The
>>> simple fact is that the human diet in no way shape or form resembles
>>> the diet of an apex predator.
>>
>> I've not had any training in ecology, but it struck me while reading
>> this thread that pre-agriculture humans may indeed be apex predators.
>> Would this be accurate?
>
> That's how it seems to me. If omnivorous brown bears can be
> categorized as apex predators, I don't see why Eskimos, or various
> cattle herders wouldn't be also.
>
> http://en.wikipedia.org/wiki/Apex_predator

I don't know how trustworthy that Wikipedia article is on the subject.
The text is quite short, focusing at length on one example of the
ecological consequences of adding an apex predator to a system, and the
texts associated with the pictures seems a bit more concerned with the
awesome fierceness of the organisms mentioned than technical
calculations of their trophic level. They also bring up the T.Rex as
"one of the supreme predators of its time", when IIRC we don't really
know whether that's true or not.

[Jimbo]

The captions on the pictures do seem a bit off. But the first part of
the article, I think, is relevant. If the article referenced by Ron is
attempting to assign a fixed trophic level to our own species, it may
be missing the point. Is it even possible to assign a specific trophic
level to our species as a whole? Trophic level varies with different
populations and changes over time. That isn't how it works with other
species.

[Arkalen]

For one thing, it could be a matter of where your energy intake comes
from by percentage, with brown bears being omnivorous yet only getting a
small proportion of their energy intake from plants.

But that said, do you have a cite on Brown bears being apex predators ?
I've tried Googling but have found contradictory results. But if you did
get your info from the Wikipedia page I guess that would answer your
question, since that page also says humans are apex predators. In other
words, given the Wikipedia disagrees with the article we're talking
about, for all we know said article wouldn't call brown bears apex
predators either.

[Jimbo]

On Sat, 07 Dec 2013 13:02:22 -0700, Richard Norman
<r_s_n...@comcast.net> wrote:

But Brown bears, with the possible exception of the polar bear
subspecies, are also omnivores. Are the apex predators or not? Well,
no other predators prey on them, except for humans. Paleolithic
Europeans apparently had the formidable cave bears as at least an
occasional item in their diet. Of course the bears no doubt also dined

sometimes on humans. Did they trade off the apex predator role in
different situations? I don't think our own ecological patterns can be

adequately encompassed within the standard scheme of categorization

that is routinely applied to other species.

[Jimbo]

The Wikipedia article could be improved, but is there some unambiguous
and definitive definition of the term 'apex predator?' And, if so, can
it be applied to all human populations now and in the past? If we're
down to quibbling about relative percentages of meat intake then it
seems to me once again that the term can't adequately encompass the
variety of human ecological interactions.

[Robert Carnegie]

On Friday, 6 December 2013 15:04:48 UTC, Richard Norman wrote:
> I think we went through this once before. According to the ecological
> definition, we are not apex predators. Whether you think that is not
> a good way to define it doesn't change its use in ecology.
>
> Sadly, your attitude seems to be sort of a peevish reaction to
> discovering that we are not the end-all and be-all of life. It is
> like the reaction of those bothered by the fact that we are apes. Why
> should it be necessary for us to be "the" apex predator just because
> we are terribly selfish bullies in our behavior within the ecosystem?

Surely not that God said after the Flood that, having saved
all the animals, we are now allowed to eat them.

[Vincent Maycock]

On Sat, 07 Dec 2013 20:21:50 +0000, Arkalen <ark...@inbox.com> wrote:

Right. T. Rex may have been a scavenger rather than an apex predator,
and there may have been predators larger than T. Rex.

[RonO]

The subject is what are apex predators. Humans obviously qualify in the
only ways that matter. It isn't so much about ecology as ridiculous
classification. It is as stupid as if cladists had concentrated on fins
and body shape so that they could classsify whales as fish and miss what
whales actually are. Reality is that simple in this case. Why can
humans affect the ecology so drastically? If you ignore reality what do
you end up with? Whales as fish.

Ron Okimoto

[Steven L.]

On 12/7/2013 9:14 AM, Walter Bushell wrote:
> In article <l7u95...@news1.newsguy.com>,
> William Morse <wdNOSP...@verizon.net> wrote:
>
>>
>> Sadly, currently we are the end-all and be-all of most of the megafauna
>> on earth. We are exterminating much of it. That turns out to have
>> profound impacts on ecosystems. And we don't have any idea what those
>> impacts are.
>
> In broad detail we do, disaster for us.

PROVE IT.

Was it a disaster for cavemen when they hunted the mammoths to extinction?

Or when the ancient Hebrews and their contemporaries deforested the
Levant, driving large animals (except for camels) deeper into Africa?

Or when the arriving Europeans exterminated the vast herds of buffalo
and bison that used to cover much of the North American continent?

Nope.

We brought our own. Europeans brought domesticated horses to North America.

Humans have been hunting megafauna for thousands of years. But what you
have evidently ignored is that while that might be a problem for the
existing ecosystem, we can change that ecosystem, by replacing large
wild animals with large domesticated animals.




--
Steven L.

[Richard Norman]

Possibly you should read the paper to see what the actual subject
matter is.

[RonO]

The subject matter was trophic level which obviously is not a good
indicator of what an apex predator is. Just like fins and body shape
aren't the defining attribute of fish or whales.

Ron Okimoto

[Walter Bushell]

In article <81l6a9pk20orpn75c...@4ax.com>,

I don't think any human population is Apex predators and if any are
close they have fallback foods

[Richard Norman]

Yes the subject matter was exactly trophic level. The paper reports
"Specifically, trophic levels describe the position of species in a
food web, from primary producers to apex predators" indicating that
"apex predator" in this instance, as is the case in a very large
number of papers in ecology, is at the highest trophic level.

The article also states: "We find significant links between HTL [human
trophic level] and important World Bank development indicators, giving
insights into the relationship between socio-economic, environmental,
and health conditions and changing dietary patterns"

The article is about food, nutrition, agricultural patterns and such,
not about environmental devastation.

Just because a research paper describes what the authors wanted to
study and not what you would have preferred them to study is no reason
to dismiss it.

[Jimbo]

On Sun, 08 Dec 2013 11:20:28 -0500, Walter Bushell <pr...@panix.com>
wrote:

Is there some single defining feature that makes a species an apex
predator? And can this feature be applied to individual human
populations? Or is there some defining set of features with some
counting more heavily than others? The terminology seems vague and
ambiguous, at least when attempts are made to apply it to human
beings.

It even seems somewhat vague when applied to creatures like wolves.
Among some wolf populations at least, mice or other small rodents
along with vegetable foods, make up a good part of the diet at certain
times of the year. Does their trophic level shift at times? Or is the
'average diet' of many different wolf populations considered to
determine the trophic level of the species as a whole?

However the determination is made with respect to other species, it's
clearly not applicable in the same way to human populations. If you
don't consider the Sioux, or Eskimos to have been apex predators, why
not? Do you consider grizzly bears to be apex predators? Why or why
not? What do fallback foods have to do with it? If the utilization of
fallback foods disqualify humans and bears from being apex predators,
do they also disqualify wolves?

[Jimbo]

How did they determine the trophic level of individual human
populations? Or did they consider this question at all?

[Jimbo]

On Sun, 08 Dec 2013 08:50:59 -0800, Jimbo <Jimbol...@nospam.com>
wrote:

Uh, Walter... I've reread this post and it may come off as rude. I
wasn't criticizing you for doubting that humans are ever apex
predators. I was just expressing my own doubts that the concept, as
it's currently understood, can be usefully applied to our own species
at all. Perhaps there's no ambiguity when it's applied to nonhuman
species, though it appears to me right now that it can be ambiguous.
But, if the authors of the study are trying somehow to average out the
past and present diets of all human populations, I think they're
employing a faulty methodology.

[Richard Norman]

On Sun, 08 Dec 2013 09:33:15 -0800, Jimbo <Jimbol...@nospam.com>

The authors are not averaging past and present diets of all human
populations. They are looking at how different populations, defined
as "country" have changed in trophic level over time as judged by
their diets. See my other post for the details of methodology.

There definitely are problems considering humans as part of any
biological ecosystem because our enormous impact is created by social
and technological factors that lie outside what biology, especially
ordinary ecology, usually considers. The human impact on the
environment far exceeds what we eat, our trophic level. The notion of
"apex predator" has nothing whatsoever to do with the paper under
consideration, though, and is an incidental mention.

The paper uses trophic level because shifts between agriculture and
animal husbandry and shifts between terrestrial meat, freshwater fish,
and marine seafood are important economically, culturally, socially,
and nutritionally in addition to ecologically. People do understand
that shifts between herbivory and carnivory have enormous impacts on
the ecology because we have to grow on the order of ten times as much
plant mass to feed our cows and sheep and chickens and pigs as we
would have to just to feed ourselves. And shifting from terrestrial
meat to aquatic creatures, both freshwater and marine, causes
devastating changes to those environments. So wouldn't knowing just
how trophic feeding levels in different parts of the world have
historically changed be important in trying to figure out how better
to live in a way that is closer to sustainable? Please don't simply
produce kneejerk simplistic solutions: eat only plants grown locally.
The problem is sociological, economic, cultural, political -- not just
biological.

[Bob Casanova]

On Sat, 07 Dec 2013 18:01:46 GMT, the following appeared in
talk.origins, posted by Nick Roberts
<tig...@orpheusinternet.co.uk>:

>In message <onh6a9p4l901u8qml...@4ax.com>
> Richard Norman <r_s_n...@comcast.net> wrote:
>
>[Snip]
>
>> The subject is not at all whether humans are destroying the ecosystem.
>> And the paper is not at all an apologetic for that destruction. The
>> simple fact is that the human diet in no way shape or form resembles
>> the diet of an apex predator.
>
>I've not had any training in ecology, but it struck me while reading
>this thread that pre-agriculture humans may indeed be apex predators.
>Would this be accurate?
>
>If so, humans may be in the unique position of being an ex
>apex predator, not because a different species got better at predation,
>but for social reasons.

Quite a few of the comments I've read in this thread seem to
assume that an apex predator (in fact, a predator in
general) is necessarily a carnivore. This doesn't seem to
square with the definition of "predator" ("an animal which
preys on others"), which only seems to exclude herbivores;
bears and humans are both predators, and I'd consider both
to be candidate apex predators. Comments?
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

- Isaac Asimov

[Jimbo]

On Sun, 08 Dec 2013 11:18:41 -0700, Richard Norman

Thanks for clearing that up. Yes, a sociological and economic analysis
of changing patterns of food production might usefully consider the
associated shifts in trophic level. But if that's what the paper's
about, I hope the authors made clear that they weren't trying to
assign any fixed trophic level to the human species itself. Terms like
'apex predator' are out of place in such a discussion. They don't
apply to our own species in the same way they might with non-human
species.

[Jimbo]

On Sun, 08 Dec 2013 11:39:53 -0700, Bob Casanova <nos...@buzz.off>
wrote:

>On Sat, 07 Dec 2013 18:01:46 GMT, the following appeared in
>talk.origins, posted by Nick Roberts
><tig...@orpheusinternet.co.uk>:
>
>>In message <onh6a9p4l901u8qml...@4ax.com>
>> Richard Norman <r_s_n...@comcast.net> wrote:
>>
>>[Snip]
>>
>>> The subject is not at all whether humans are destroying the ecosystem.
>>> And the paper is not at all an apologetic for that destruction. The
>>> simple fact is that the human diet in no way shape or form resembles
>>> the diet of an apex predator.
>>
>>I've not had any training in ecology, but it struck me while reading
>>this thread that pre-agriculture humans may indeed be apex predators.
>>Would this be accurate?
>>
>>If so, humans may be in the unique position of being an ex
>>apex predator, not because a different species got better at predation,
>>but for social reasons.
>
>Quite a few of the comments I've read in this thread seem to
>assume that an apex predator (in fact, a predator in
>general) is necessarily a carnivore. This doesn't seem to
>square with the definition of "predator" ("an animal which
>preys on others"), which only seems to exclude herbivores;
>bears and humans are both predators, and I'd consider both
>to be candidate apex predators. Comments?

The term usually refers to 'top' predators which aren't themselves
prayed upon and which serve to stabilize their ecosystems and keep
them 'healthy.' By that criterion bears usually qualify but humans
often don't. We haven't physically adapted to a specific ecological
niche, so we tend to destabilize ecosystems as much or more than we
stabilize them.

I don't think being a pure carnivore is a necessary feature. Cats are
pure carnivores but canids and ursids aren't. Their backteeth are
adapted both to slicing meat and to grinding vegetation. Felines have
slicing backteeth with no grinding surface, and their digestive system
is adapted to a pure meat diet. So being an apex predator refers to
the role in an ecological community rather than to the percentage of
meat intake.

As for human beings, the ecological term just doesn't apply to the
species as a whole because different groups can figure out different
ways to live that incorporate different sets of ecological
interactions. It's like how the laws of physics break down when
attempts are made to apply them to the center of black holes. Some of
the laws of ecology just don't apply to our own species in the same
way they apply (more or less) to every other sort of living thing.

[Richard Norman]

On Sun, 08 Dec 2013 11:39:53 -0700, Bob Casanova <nos...@buzz.off>
wrote:

>On Sat, 07 Dec 2013 18:01:46 GMT, the following appeared in
>talk.origins, posted by Nick Roberts
><tig...@orpheusinternet.co.uk>:
>
>>In message <onh6a9p4l901u8qml...@4ax.com>
>> Richard Norman <r_s_n...@comcast.net> wrote:
>>
>>[Snip]
>>
>>> The subject is not at all whether humans are destroying the ecosystem.
>>> And the paper is not at all an apologetic for that destruction. The
>>> simple fact is that the human diet in no way shape or form resembles
>>> the diet of an apex predator.
>>
>>I've not had any training in ecology, but it struck me while reading
>>this thread that pre-agriculture humans may indeed be apex predators.
>>Would this be accurate?
>>
>>If so, humans may be in the unique position of being an ex
>>apex predator, not because a different species got better at predation,
>>but for social reasons.
>
>Quite a few of the comments I've read in this thread seem to
>assume that an apex predator (in fact, a predator in
>general) is necessarily a carnivore. This doesn't seem to
>square with the definition of "predator" ("an animal which
>preys on others"), which only seems to exclude herbivores;
>bears and humans are both predators, and I'd consider both
>to be candidate apex predators. Comments?

In ecology, trophic levels are a very important idea because of the
flow of energy between levels: there is roughy a 90% "loss" between
levels, only 10% of the caloric content of one level being made
available to the next higher level feeding on them. I put "loss" in
quotes because that energy is lost only in terms of producing new
biomass. It really is used to carry out the functions of life and to
reproduce which are certainly not losses in the more general sense.

The important terms in ecology are producers, making biomass from
inorganic substances and using external sources of energy, mostly
sunlight, and consumers, feeding on other organisms for energy and
chemical substrates. We are familiar with these as "plants" and
"animals" but fungi are consumers there are both consumers and
producers in the microbe world. In turn, consumers can be first order
(eating producers), second order (eating first order consumers), and
so on. In terrestrial habitats, the "top level" trophic level is
usually a tertiary consumer, something that eats not just carnivores
but carnivores that themselves feed on carnivores. An example would
be a hawk they preys on owls who prey on mice who eat plants. Aquatic
ecosystems are very different because of the tiny size and abudance of
the usual planktonic producers. This allows for a wide variety of
invertebrate herbivores, also tiny, to be eaten by fish who are then
eaten by bigger fish and so on. So there tend to be more trophic
levels in aquatic systems although the limiting energetics still keeps
the chain rather short.

It is quite obvious that there are many carnivores who feed at more
than one trophic level. That is why there is a food "web" rather than
a simple food "chain" or ladder of levels. You can readily compute an
"effective trophic level" as a weighted average of feeding. If 40% of
your food comes from level 1 (plants) and 60% from level 2
(herbivores), then you are at trophic level 1.4. That is exactly the
notion of trophic level used in the paper.

I do all this because those are the important "pure" concepts. Then
there are terms whose usage is sometimes variable, terms like
"predation" and "apex predator". Ordinarily predation means feeding
on animals. Grazing and parasitism are means of "preying" on others
but are considered different. Even herbivores that kill the plants
they eat are not ordinarily considered to be predators. Sometimes
even predation, selectively seeking out which organisms to eat, is
separated from filter feeding where you indiscrimitately eat
everything you manage to catch.

Apex predator merges two concepts, sometimes applied with different
force by different users for different purposes. One is that the apex
predator is at the top of the food chain, the highest level consumer.
Ordinarily that means that it is a tertiary or even a quaternary
consumer on land. In marine systems it would ordinarily be a fifth
level consumer. A second aspect is that the apex predator has no
"natural enemies". That is, there is nothing that normally preys on
it. Detritus feeding and scavenging already dead carcasses is a
separate category. Modern humans, as has been pointed out many times,
have an effect on the ecosystem far in excess of simple trophic
feeding. But to concentrate simply on feeding, our trophic level is
somewhere between 2 and 3 meaning most populations do get a reasonable
abount of nutrition from aquatic carnivores. Even most hunter
gatherers don't many calories from eating terrestrial carnivores.
Since there are many organisms at trophic level 3 to 4, he don't
qualify. Also, before the advent of modern technology (and still
continuing today in many parts of the world) there are plenty of
predators that regularly take humans as food. Again, we fail to
qualify as unambiguous apex predators.

[Richard Norman]

On Sun, 08 Dec 2013 08:53:23 -0800, Jimbo <Jimbol...@nospam.com>

From the "Materials and Methods" section of the paper:

The HTL is a mean of the trophic level of food items in the diet,
weighted by quantity. It is calculated as
HTL =1 + Sigma(Qi * TLi)/Sigma Qi
where Qi is the quantity (in kilograms) of the food item i consumed,
and TLi is the trophic level of the food item. We use the FAO national
data on the human food supply per food item per capita per year
(1961�2009). The FAO human food supply data represent each country�s
production of foodstuffs for human consumption, accounting for
imports, exports, and food used for livestock (SI Appendix). Food
supply data are available for 176 of 196 countries.

We assume that food supply is a good proxy for food consumption,
although it includes waste (21). The trophic level of each food item
is gathered from the literature (SI Appendix, Table S1). We assume
that the trophic level for animals was constant between countries,
although there is likely to be variability due to differences in feed
and production methods of the lower trophic levels.

Note: the SI Appendix includes some 50 pages of data, charts, and
tables. The food we eat includes mostly trophic levels 1 (plants) and
2 (herbivores). Some types of seafood goes up to trophic level 3
(carnivore that eat herbivores) or even higher (carnivores that eat
other carnivores). Most "apex predators" are trophic level 5 meaning
that they include trophic level 4 in their diet.

Note: aquatic ecosystems generally have higher trophic levels than
terrestrial. Most of us eat virtually nothing terrestrial higher than
trophic level 2 (the paper used a value of 2.05). Aquatic mammals,
though, are at trophic level 4 but none of the populations studies ate
any substantial amount of that kind of food. Yes, people here have
referred to arctic peoples but this paper did not have data for that
specific group.

The major factors controlling human trophic level is the relative
proportion of plant matter, terrestrial meat, and seafood in the diet.
Increasing quatities of meat and, especially seafood, are the reasons
for changing trophic levels.

[James Beck]

Good for you. I'm surprised that PNAS would take such a crappy paper.

[Richard Norman]

On Sun, 08 Dec 2013 14:02:22 -0700, James Beck <jdbec...@yahoo.com>

Have either you or Ron actually read the paper to see whether it is
really crappy?

[Jimbo]

On Sun, 08 Dec 2013 13:18:36 -0700, Richard Norman

Thanks. The study is limited in the sorts of economies they
considered, but apparently they weren't attempting to characterize
human ecological interaction in the same way that we can characterize
the ecologies of non-human organisms. They were talking about economic
institutions and means of production. If the paper contributes to a
better understanding of the impacts of shifting patterns of resource
utilization on terrestrial and marine ecosystems, that's all to the
good.

I think Ron's comments and my own were based on the idea that they
were trying to make generalizations that apply to the species as a
whole. If they make a blanket statement that humans aren't apex
predators, they're neither wrong nor right. We can interact with
habitat in ways that correspond to the interactions of apex predators,
or to grazers. They would simply be misapplying the terminology. The
ordinary categorizations just don't apply.

..

[James Beck]

The real question is why you can't tell at a glance that it's crap.

[Richard Norman]

On Sun, 08 Dec 2013 13:10:57 -0800, Jimbo <Jimbol...@nospam.com>

Ron's comments were based on misreading and misinterpreting what was
written in the abstract of the paper that he cited. Your comments and
those of others then seemed to be based on Ron's presentation rather
than on what the original authors either intended or wrote.

Here are the conclusions from the abstract that was available to Ron:

"We find significant links between socio-economic and environmental
indicators and global dietary trends. We demonstrate that the HTL is a
synthetic index to monitor human diets and provides a baseline to
compare diets between countries"

In other words, there is absolutely no reason to think that this paper
deals with whether or not humans are "apex predators" except
incidentally where they clearly define "apex predator" as having a
trophic level of 5 whereas they show that the human trophic level is
between 2 and 3.

[Richard Norman]

On Sun, 08 Dec 2013 14:16:08 -0700, James Beck <jdbec...@yahoo.com>

Generally I try to read and understand the content before making such
judgements.

Can you provide cogent arguments based on the actual content of the
paper to indicate that it is crap?

[Jimbo]

On Sun, 08 Dec 2013 14:24:43 -0700, Richard Norman

Lions and tigers are at trophic level 3. They can feed on both primary
and secondary producers. So do some humans. I think that's what Ron
was getting at. The paper claims to have measured a 'human trophic
level' which gives the impression that they're using the term in the
same way it's applied to non-human species' ecological interactions.
Actually they're using food production statistics in the surveyed
countries to calculate this 'HTl'. This may serve their purposes and
may even be useful in some ways, but it doesn't correspond to what is
generally meant when ecologists refer to the trophic level of a
non-human species within a particular ecosystem. It's an analogy and
in some respects it's not a good one.

[Richard Norman]

On Sun, 08 Dec 2013 14:12:34 -0800, Jimbo <Jimbol...@nospam.com>

First you are wrong about lions and tigers. Herbivores feed on
primary producers. Lions and tighers feed on primary or secondary
carnivores. That means they are between 3 and 4. Humans rarely eat
terrestrial carnivores (level 3) and when they do it forms just a very
small part of their diet. The question is not what some humans or
some other species does some of the time. It is what forms the most
important parts of the diet calorically. That is why the weighted
average used in this paper is necessary. It accounts for feeding at
multiple levels.

Second you are wrong about the impression given by the paper. They
use the term exactly in the same way that it is applied to non-human
species ecologial interactions. They do not use food production by
region to do the calculation. They use food supply by region. That
is different, for example, to a region that grows a lot of grain but
imports a lot of meat for consumption. They do say that food supply
does not equal food eaten because it does not account for waste. But
they do say it is a good proxy and, in those regions where food is
scarce, is a very accurate one.

I think a problem is that trophic level does not so much correspond to
what you kill but rather to what you eat. The biological notion is
strictly based on eating. When biologists refer to the trophic level
of a non-human species within a particular ecosystem they refer
exactly to what these researchers tried to study.

I really do not understand why people have trouble accepting this
study for what it is rather than criticizing it for what it is not.

[Jimbo]

On Sun, 08 Dec 2013 15:28:10 -0700, Richard Norman

We could quibble about whether lions and tigers and bears eat more
humans or humans eat more lions, tigers and bears. In some countries
the eating of cats and especially great cats is thought to increase
one's chi, and I've personally eaten bear meat. I've also eaten tuna,
salmon and even shark. Well, maybe I'm not typical. That's the point -
there is no universal or even 'typical' human diet. Some peoples diets
are rich in fruit and nuts, while others rely heavily on rice. The
plains Indians relied almost exclusively on the bison. And Eskimos ate
fish, seal and also polar bears that ate fish and seal.

Perhaps the authors of the paper under discussion didn't consider it
necessary to take account of the trophic level of traditional Eskimos,
but then they should make clear that their 'HTL' doesn't correspond to
the 'LTL' of lions or the 'TTL' of tigers.

>Second you are wrong about the impression given by the paper. They
>use the term exactly in the same way that it is applied to non-human
>species ecologial interactions. They do not use food production by
>region to do the calculation. They use food supply by region. That
>is different, for example, to a region that grows a lot of grain but
>imports a lot of meat for consumption. They do say that food supply
>does not equal food eaten because it does not account for waste. But
>they do say it is a good proxy and, in those regions where food is
>scarce, is a very accurate one.

How does that correspond to non-human species' ecological
interactions? In a region dominated by rice farming the trophic level
of the farmers will be different from that of fisher people or hunters
like the Sioux.

>I think a problem is that trophic level does not so much correspond to
>what you kill but rather to what you eat. The biological notion is
>strictly based on eating. When biologists refer to the trophic level
>of a non-human species within a particular ecosystem they refer
>exactly to what these researchers tried to study.

The difference is that different human populations can and do create
different patterns of ecological interaction while other species
maintain a single species-wide pattern of ecological interactions. The
authors of this study seem to think it's alright to sample food
production in certain countries and from that calculate a 'HTL' for
the entire human species. That kind of measure may be what they're
after for their particular purposes, but it doesn't correspond with
the way trophic level is assigned to non-human species.

>I really do not understand why people have trouble accepting this
>study for what it is rather than criticizing it for what it is not.

Tell them to find some other term for what they measured. It's wrong
to characterize it as a measure of a universal 'human trophic level.'

[Richard Norman]

On Sun, 08 Dec 2013 15:04:02 -0800, Jimbo <Jimbol...@nospam.com>

Perhaps if you read the paper you would realize that the whole purpose
was to look at the differences in trophic levels of different groups
of people as well as how the trophic level of one group has changed
with time. You are the one who insists that HTL necessarily refers to
a universal human attribute. The "human" value represents a rough
average of all the groups. The Inuit were not studied because no data
was available for that particular group. Also you may be interested
that modern Inuit get most of their food from a grocery store. Still
they did have data for 176 countries and about 98% of the total human
population. Yes, trophic level differs by class and socioeconomic
status within a single country. My granddaughter insisted on being a
vegetarian for a short time (until she discovered that bacon would
then be excluded). So does that mean that I have to recalculate my
notion of a regional or population trophic level because some
individuals have weird or specialized feeding habits?

You still do not understand the "weighted average" of trophic feeding.
If you eat an occasional high level carnivore it does not change the
population average by any considerable degree. The question is: where
do the bulk of calories come from?

I already said that eating marine seafood puts you higher in the
trophic level than eating terrestrial animals. Still, count calories
and see what percentage comes from what kind of meat in general for a
large group of people and what percentage comes from plant matter.

[John S. Wilkins]

Nominated as being very informative.

--
John S. Wilkins, Associate, Philosophy, University of Sydney
http://evolvingthoughts.net
But al be that he was a philosophre,
Yet hadde he but litel gold in cofre

[Richard Norman]

On Sun, 08 Dec 2013 15:04:02 -0800, Jimbo <Jimbol...@nospam.com>
wrote:

<snip>

>
>The difference is that different human populations can and do create
>different patterns of ecological interaction while other species
>maintain a single species-wide pattern of ecological interactions. The
>authors of this study seem to think it's alright to sample food
>production in certain countries and from that calculate a 'HTL' for
>the entire human species. That kind of measure may be what they're
>after for their particular purposes, but it doesn't correspond with
>the way trophic level is assigned to non-human species.
>
>>I really do not understand why people have trouble accepting this
>>study for what it is rather than criticizing it for what it is not.
>
>Tell them to find some other term for what they measured. It's wrong
>to characterize it as a measure of a universal 'human trophic level.'

Let me illustrate me point by quoting from the actual paper to
illustrate that people really have to look at the source before
criticizing something based on impressions. See if this is the work
of people who do not understand that different human populations at
different times have different eating patterns.

------ start of quoted material ----------------------

We find the global median HTL in 2009 to be 2.21 (SD = 0.13).
This represents a percentage increase of 3% since 1961 (Fig.
1A). The median HTL is weighted by the population size of each
country, and thus this trend is mainly driven by China and India,
whose median HTL has increased from 2.05 to 2.20 during this
period (+7.4%; Fig. 1A). When these countries are removed
from the analysis, the global HTL is stable over time at 2.31
(Fig. 1A).

HTL has a broad range of values that reflects large variations
in diet between countries and over time (Fig. 1B). For example,
in 2009, Burundi had an HTL of 2.04, representing a diet that is
almost completely (96.7%) plant based. In contrast, Iceland had
an HTL of 2.57 for the same year, representing a diet composed of 50%
meat and fish and 50% plants (SI Appendix, Fig. S5).
Likewise, we find a wide range of values within countries over
time, e.g., Iceland�s HTL has decreased dramatically since 1974,
when it was 2.76 (-7%).

Although there is remarkable diversity in diet between the 176
countries of this study...

------ end of quoted material ----------------------

OK, nothing "universal" here, folks, except for taking a weighted
average over all the groups studied and clearly stating that is what
is being done.

[Burkhard]

On Sunday, December 8, 2013 11:46:34 PM UTC, John S. Wilkins wrote:

Seconded, one of the most informative exchanges in a long time

[Jimbo]

And specifying that these figures apply only to the year 2009. I
appreciate that they were trying to analyze broad human trends. Still
I think a term like 'current weighted mean human trophic level' would
be more accurate. More cumbersome though. At any rate I admit that I
would have been less critical if I'd read the paper.

[Richard Norman]

On Sun, 08 Dec 2013 17:04:48 -0800, Jimbo <Jimbol...@nospam.com>

Perhaps your evaluation would have been less critical if you also had
know that they analyzed data for every year from 1961 through 2009 to
see trends as various parts of the world started to transition to more
developed socioeconomic status.

Perhaps Ron would have been less critical had he read that

---------- start quoted section -----------------

Positioning Humans in the Food Web. Humans dominate
ecosystems through changes in land use, biogeochemical cycling,
biodiversity, and climate (11, 13, 14). It is not sufficient to
separate
humans from analyses of ecosystem processes, because
there are no remaining ecosystems outside of human influence
(15). Thus, investigations of ecosystems, without accounting for
the presence of humans, are incomplete (13). There is a variety
of other ecological indicators based on trophic ecology theory or
diets, e.g., the omnivory index, that may also prove useful in
assessing the impact of humans in the functioning of ecosystems.
However, a first estimate of an HTL gives us a basic tool that
places humans as components of the ecosystem and assists in
further comprehending energy pathways, the impact of human
resource use, and the structure and functioning of ecosystems.

-------------- end quoted section --------------------------

He also may not have been so critical had he read the section saying
"For carnivorous apex predators, such as polar bears or killer
whales, trophic levels range up to 5.5". Compare that to humans at a
globally averaged value or 2.21 +/- 0.13.

In any event it really does pay to actually read a paper before
totally trashing it.

[Walter Bushell]

In article <gha9a91gsdqovembv...@4ax.com>,

Jimbo <Jimbol...@nospam.com> wrote:

> Uh, Walter... I've reread this post and it may come off as rude. I
> wasn't criticizing you for doubting that humans are ever apex
> predators. I was just expressing my own doubts that the concept, as
> it's currently understood, can be usefully applied to our own species
> at all. Perhaps there's no ambiguity when it's applied to nonhuman
> species, though it appears to me right now that it can be ambiguous.
> But, if the authors of the study are trying somehow to average out the
> past and present diets of all human populations, I think they're
> employing a faulty methodology.

OK, no offense, if I were easily offended I wouldn't dare post here,
or even read here, and I agree the idea of apex predator is kinda
shaky. The food chain in a cycle after all as Edgar Allen Poe pointed
out graphically and Shakesphere before him. Eventually every plant or
animal ends up as scavenger food. And then there are the parasites,
see _Parasite Rex_, which makes the case that it's parasites that
allow predation. Getting sick for a zebra, means being an easy prey.

I suppose getting cremated allows humans to avoid being worm food, but
burial at deep sea also works means being eaten by jawless fish.
Whales falling to the deep are known to nourish whole ecosystems for
years.

--
Gambling with Other People's Money is the meth of the fiscal industry.
me -- in the spirit of Karl and Groucho Marx

[Walter Bushell]

In article <e7h9a953adftd3v1h...@4ax.com>,

Jimbo <Jimbol...@nospam.com> wrote:

> As for human beings, the ecological term just doesn't apply to the
> species as a whole because different groups can figure out different
> ways to live that incorporate different sets of ecological
> interactions. It's like how the laws of physics break down when
> attempts are made to apply them to the center of black holes. Some of
> the laws of ecology just don't apply to our own species in the same
> way they apply (more or less) to every other sort of living thing.

I'd like to restate that as "Ecologies including humans need more
general laws than those that don't include humans." Humans though do
require foods of high nutrient density. We cannot extract much food
value from leaves because our ancestors lost the ability to process
leaves and grass and went to nutritionally dense foods such as meat,
fruit and roots. This makes us even more disruptive to ecologies than
grass eats would be for our numbers.

[Walter Bushell]

In article <1ldlxqt.rmq35epgqr3bN%jo...@wilkins.id.au>,

<SINP><

Second.

[RonO]

>>>>> The subject is not at all whether humans are destroying the ecosystem.
>>>>> And the paper is not at all an apologetic for that destruction. The
>>>>> simple fact is that the human diet in no way shape or form resembles

No one said that trophic levels were not good for something, they just
aren't a good trait to define apex predators. To miscatagorize
something like humans can have a huge impact on the environment and
eventual socio-economic levels of the majority of humans.

Ron Okimoto

[Jimbo]

On Sun, 08 Dec 2013 19:32:04 -0700, Richard Norman

Did they find anything that provides significant new insight into the
socio-economic trends they analyzed? If they discovered that people in
some countries can afford to eat more meat nowadays, and chose to do
so, or that increased exploitation of fisheries is damaging ecosystems
and causing some fisheries to crash, then that's pretty much something
that most people already know.

>Perhaps Ron would have been less critical had he read that
>
>---------- start quoted section -----------------
>
>Positioning Humans in the Food Web. Humans dominate
>ecosystems through changes in land use, biogeochemical cycling,
>biodiversity, and climate (11, 13, 14). It is not sufficient to
>separate
>humans from analyses of ecosystem processes, because
>there are no remaining ecosystems outside of human influence
>(15). Thus, investigations of ecosystems, without accounting for
>the presence of humans, are incomplete (13). There is a variety
>of other ecological indicators based on trophic ecology theory or
>diets, e.g., the omnivory index, that may also prove useful in
>assessing the impact of humans in the functioning of ecosystems.
>However, a first estimate of an HTL gives us a basic tool that
>places humans as components of the ecosystem and assists in
>further comprehending energy pathways, the impact of human
>resource use, and the structure and functioning of ecosystems.
>
>-------------- end quoted section --------------------------
>
>He also may not have been so critical had he read the section saying
>"For carnivorous apex predators, such as polar bears or killer
>whales, trophic levels range up to 5.5". Compare that to humans at a
>globally averaged value or 2.21 +/- 0.13.

I'm not so sure about that. How useful is a globally averaged value?
Traditional Eskimos, including the Inuit, ate the same seals and fish
that killer whales and polar bears eat. They also wore polar bear
hides, and didn't waste the meat. Their trophic level would have been
at least as high as that of the bears. A globally averaged value
completely misses the wide variation in human diet that has existed
until recently. It focuses completely on modern
agricultural-industrial means of food production and utilization.

OK, fine, that's what they set out to do. I understand that they were
attempting to do a cross-disciplinary study incorporating ecological
concepts into the socio-economic analysis of food production and
utilization trends. But what does it all amount to? Their global
weighted mean human trophic level may be somewhat useful, but it
doesn't appear to be 'the basic tool' they make it out to be. It's
perhaps a marginally useful measure of shifting diets in
agro-industrial economies. It would have been useful perhaps to
emphasize that it's not a basic feature of human ecology, but rather a
measure of shifts in particular culture's food habits.

I still think Ron is correct in his basic complaint. The authors are
trying to take an old-fashioned socio-economic trend analysis and
dress it up in the language of ecology. So far as I can tell from the
sections of the paper you've excerpted, the language contributes very
little to a better understanding of the underlying dynamics of human
social, cultural and economic change. In order to understand human
socio-economic change you need to understand how reshaped Pliocene
apes can function ecologically as apex predators in one place and
vegetarian farmers in another. Not only does this paper contribute
nothing to that understanding, it ignores precisely those types of
data that could lead to such an understanding.

>In any event it really does pay to actually read a paper before
>totally trashing it.

Sure, I agree. But from what you said and the sections you've
excerpted, it doesn't appear worth reading. The analysis seems fairly
misdirected and superficial. I may be wrong. What's the most
significant insight you took from it?

[Richard Norman]

On Mon, 09 Dec 2013 05:53:27 -0500, Walter Bushell <pr...@panix.com>
wrote:

Wow, wait until the ecologists learn about this! It will completely
change their notions of food webs!!!

Please, the fact that a scavenger or decomposer feeds on the dead body
of a polar bear does not mean that the fungi are apex predators. In
ecology there are energy flows described by trophic levels which are
NOT cyclic. Then there are material cycles: carbon, nitrogen,
water... which are. Ecologists do not confuse the two concepts but
just looking at who eats what superficially does.

[Jimbo]

On Mon, 09 Dec 2013 06:04:25 -0500, Walter Bushell <pr...@panix.com>
wrote:

>In article <e7h9a953adftd3v1h...@4ax.com>,
> Jimbo <Jimbol...@nospam.com> wrote:
>
>> As for human beings, the ecological term just doesn't apply to the
>> species as a whole because different groups can figure out different
>> ways to live that incorporate different sets of ecological
>> interactions. It's like how the laws of physics break down when
>> attempts are made to apply them to the center of black holes. Some of
>> the laws of ecology just don't apply to our own species in the same
>> way they apply (more or less) to every other sort of living thing.
>
>I'd like to restate that as "Ecologies including humans need more
>general laws than those that don't include humans." Humans though do
>require foods of high nutrient density. We cannot extract much food
>value from leaves because our ancestors lost the ability to process
>leaves and grass and went to nutritionally dense foods such as meat,
>fruit and roots. This makes us even more disruptive to ecologies than
>grass eats would be for our numbers.

You have a point. On the other hand, with the right know-how and
equipment, we can rig up a digester that ferment leaves in a big vat,
and break down their cellulose that way. Humans have developed all
sorts of tricks and work-arounds. Manioc can be rendered non-poisonous
through proper treatment, as can a variety of other foods. Non-human
species can't do this sort of thing. They either have the digestive
apparatus that can deal with the unprocessed food item or they don't.
Even in the case of leaf-cutter ants who create mold 'gardens', the
process is part of their innate biology. So, in this sense, ordinary
ecological constraints don't exist for humans whose traditions
incorporate various culturally transmitted food-processing techniques.

[Richard Norman]

On Mon, 09 Dec 2013 06:41:39 -0800, Jimbo <Jimbol...@nospam.com>

Once again, you criticize the paper for being what you want it to be,
not for what it is.

I think it is time to revert to the long-standing classroom practice:
if you didn't read the material in preparation for a discussion,
please leave the class.

[Richard Norman]

Is it necessary to repeat it once again? I guess it is.

The paper is not about defining apex predators nor is it about whether
humans are apex predators or not. The paper is not about whether
humans have a huge impact on the environment. It is about what
different populations of humans eat.

[Richard Norman]

On Mon, 09 Dec 2013 06:04:25 -0500, Walter Bushell <pr...@panix.com>
wrote:

>In article <e7h9a953adftd3v1h...@4ax.com>,
> Jimbo <Jimbol...@nospam.com> wrote:
>
>> As for human beings, the ecological term just doesn't apply to the
>> species as a whole because different groups can figure out different
>> ways to live that incorporate different sets of ecological
>> interactions. It's like how the laws of physics break down when
>> attempts are made to apply them to the center of black holes. Some of
>> the laws of ecology just don't apply to our own species in the same
>> way they apply (more or less) to every other sort of living thing.
>
>I'd like to restate that as "Ecologies including humans need more
>general laws than those that don't include humans." Humans though do
>require foods of high nutrient density. We cannot extract much food
>value from leaves because our ancestors lost the ability to process
>leaves and grass and went to nutritionally dense foods such as meat,
>fruit and roots. This makes us even more disruptive to ecologies than
>grass eats would be for our numbers.

Would you say the same about birds, that they are disruptive to
ecologies, because they also eat those nutritionally dense foods you
mention instead of leaves? Well, about 97% of birds do and only about
3% eat leaves and those tend not to fly.

It is also true that many animals in temperate zones change their
diets drastically in different seasons. Migratory animals tend to
occupy different ecosystems at different seasons. Many animals are
widely distributed around the globe occupied different habitats and
ecosystems in different areas. We are not the only organisms that "

[Jimbo]

It's possible, Richard, that You're missing the implication of
Walter's post. Ecosystems are stabilized by the niche specialization
of various bird species. Each species utilizes a slightly different
resource or has a different method of utilization. Stable resource
partitioning occurs. Alien species can disrupt the system, but
eventually a new equilibrium develops. Humans, however, are different.
We constantly come up with new techniques of utilization and
exploitation that are highly disruptive. Right now we're degrading
ecosystems everywhere.

[Jimbo]

On Mon, 09 Dec 2013 08:00:13 -0700, Richard Norman

So, young Richard... It appears that you can't share with the class
the most significant insight you took from this paper. Perhaps you
should reread it and perhaps you will find something of value within
it.

[Richard Norman]

On Mon, 09 Dec 2013 07:33:43 -0800, Jimbo <Jimbol...@nospam.com>

I think I have a different take on Walter's post. In describing the
human practice of feeding on high density nutrients he said " This

makes us even more disruptive to ecologies than grass eats would be

for our numbers." And you previously said: "As for human beings, the

ecological term just doesn't apply to the species as a whole because
different groups can figure out different ways to live that
incorporate different sets of ecological interactions."

It is very true that we humans have, through cultural and social
inheritance, come up with technology that makes us highly disruptive.
It is very true that we are degrading ecosystems everywhere. What is
not true are the reasons you and Walter give. It is not that we feed
on high nutrient density foods: birds do that but are not disruptive.
It is not that we figure out different ways to live in different
ecosystems: many animals do that but are not disruptive.

I noted that our technology arises primarily through cultural and
social inheritance that lets us transmit knowledge across generations.
That is something beyond biological inheritance and makes us very
different from other species. Part of our destructivenessd arises
simply from our large population size. Any species with such numbers
and population densities causes large alterations in the ecosystem. We
usually don't say "destructive" when it is "natural" but the
"alteration" caused, say, by a locust swarm is somewhat severe and
ecosystems subject to such periodic events are very different from
those without the events. But much of our destructiveness and,
indeed, our ability to sustain large population size comes from our
modification of the environment to produce enough food and that means
technology.

[Richard Norman]

On Mon, 09 Dec 2013 07:41:12 -0800, Jimbo <Jimbol...@nospam.com>

I am not a proponent of this particular paper. I am merely trying to
correct total misinterpretation of what it is about based on the
impression of people who have not read it.

I think understanding the changing patterns of food consumption in
different countries around the world, undeveloped, developing, and
developed, is an important tool. In particular, shifts from eating
agricultural products to those of animal husbandry (herbivory to
carnivory) are very important because animal husbandry requires far
more land use (and resulting environmental impact and energy use) to
grow feed. Also in particular, shifts from eating terrestrial animals
(animal husbandry) to eating seafood (fisheries) involves other major
environmental impacts. What is clear from the paper is that the
major impact on total averaged human feeding patterns in the last
several decades has come about almost exclusively from changes in
India and China where economic and social changes resulted in eating
at higher trophic levels. There is no humane or ethical way of
preventing other populations in the world from participating in the
life style that we in the developed world enjoy. I think that
emphasizing the shift in feeding patterns by using the measure of
trophic level can help us plan better strategies to mitigate the
environmental harm we do cause.

As the paper concludes: "We find significant links between

socio-economic and environmental indicators and global dietary
trends. We demonstrate that the HTL is a synthetic index to monitor
human diets and provides a baseline to compare diets between

countries."

There is a lot more: correlating changes in trophic level with GDP,
life expectancy, CO2 production, and urbanization, for example.
Describing five patterns of feeding among the 176 countries studies is
another.

[Jimbo]

On Mon, 09 Dec 2013 08:50:29 -0700, Richard Norman

I think you're mistaken here. Other species *don't* figure out entire
new patterns of ecological interaction with habitat. Individuals of
some species - those that are ecological generalists and whose members
are relatively intelligent - may be very crafty and versatile, but
they are employing the same basic techniques and tricks as all other
members of their species. Crows, raccoons, coyotes and other
generalists can come up with new tricks. They don't come up with
entirely new ways of obtaining and processing previously unobtainable
foods and resources.

>I noted that our technology arises primarily through cultural and
>social inheritance that lets us transmit knowledge across generations.
>That is something beyond biological inheritance and makes us very
>different from other species. Part of our destructivenessd arises
>simply from our large population size. Any species with such numbers
>and population densities causes large alterations in the ecosystem. We
>usually don't say "destructive" when it is "natural" but the
>"alteration" caused, say, by a locust swarm is somewhat severe and
>ecosystems subject to such periodic events are very different from
>those without the events. But much of our destructiveness and,
>indeed, our ability to sustain large population size comes from our
>modification of the environment to produce enough food and that means
>technology.

I'm not sure that's a different take. It appears that you're agreeing
with us. Although other species, such as lynxes and hares, go through
'boom and bust' cycles, these population fluctuations (drastic though
they may be) are aspects of an ecosystem that is stable over the long
term. The current human population explosion isn't part of a stable
cycle. It's precipitating what may be the largest mass extinction the
earth has ever seen.

We don't need old-fashioned socio-economic trend analyses with
ecological terminology added as window-dressing. Such studies may
provide the illusion of greater understanding, but in fact they merely
obscure the underlying adaptational dynamic that has led us to this
situation. Understanding *how* we come up with new techniques and new
ways of incorporating these techniques is more important. A better
understanding of politics, religion and philosophy are essential.
Creating a measure of 'HTL' isn't.

[Richard Norman]

On Mon, 09 Dec 2013 08:23:43 -0800, Jimbo <Jimbol...@nospam.com>

Of course we agree on the fact that humans utilize the resources of
the environment in very different and in enormously destructive ways
unparalleled in the world of biology and that our way of life is
totally unsustainable.

What we seem to disagree on is whether the paper in question is crappy
or whether the purpose of the paper is to establish that humans are
not "apex predators." That is the general tenor of the thread that I
am responding to. You may fall into a different category of
respondent.

[Jimbo]

On Mon, 09 Dec 2013 09:13:19 -0700, Richard Norman

The shift in feeding patterns is already known to everyone who has
paid any attention to world events. An observation that the trophic
level of populations within agro-industrial nations has risen by a few
percentage points isn't going to provide significant new input to
strategies for mitigating the ongoing and accelerating catastrophe. It
may contribute to an illusion that the problems are being addressed
'scientifically,' but that's about all.

>As the paper concludes: "We find significant links between
>socio-economic and environmental indicators and global dietary
>trends. We demonstrate that the HTL is a synthetic index to monitor
>human diets and provides a baseline to compare diets between
>countries."

And you read this whole thing without once saying, "Well, DUH!"? China
and India's economies have been expanding fast for twenty years.
They're eating more meat. Mechanized trawlers are scouring the seas of
every fish that's remotely edible. Everybody who reads this paper will
probably already know this.

>There is a lot more: correlating changes in trophic level with GDP,
>life expectancy, CO2 production, and urbanization, for example.
>Describing five patterns of feeding among the 176 countries studies is
>another.

A good analysis of the five patterns of feeding may be useful, but the
'HTL' measurement seems useless.

[Richard Norman]

On Mon, 09 Dec 2013 08:55:32 -0800, Jimbo <Jimbol...@nospam.com>

You have convinced me. The paper is absolute crap. PNAS should be
ashamed of themselves for allowing such trash to appear under their
byline. And you could tell all that without even reading it for
yourself!

[Jimbo]

On Mon, 09 Dec 2013 09:37:15 -0700, Richard Norman

I may be a different category of respondent, but I agree with Ron that
humans can function ecologically in a way that corresponds to the way
a non-human apex predator might function within a particular
ecosystem. Bison hunting tribes in North America split off from tribes
that practiced a combined hunting and gathering life in a more wooded
environment. They just up and switched ecological niches while
developing new customs, values and religion. They would have jumped up
a trophic level or two, but a study that analyzed this shift wouldn't
have contributed much to an understanding of the underlying
adaptational dynamics that made possible the transition into a whole
new way of life.

Similarly, we need to understand the socio-economic, political,
religious, philosophical and motivational dynamics that underlies all
past and present shifts. How do we manage, almost unconsciously, to
weave all the threads together that create the fabric of the altered
lifestyle? We can't gain this understanding without inter-disciplinary
collaboration. The authors of this study took a stab at such
collaboration, but it's a fumbling first attempt. Hopefully future
attempts will be more successful.

[Jimbo]

On Mon, 09 Dec 2013 10:12:36 -0700, Richard Norman
<r_s_n...@comcast.net> wrote:

>On Mon, 09 Dec 2013 08:55:32 -0800, Jimbo <Jimbol...@nospam.com>
>wrote:

<snip>

>>A good analysis of the five patterns of feeding may be useful, but the
>>'HTL' measurement seems useless.
>
>You have convinced me. The paper is absolute crap. PNAS should be
>ashamed of themselves for allowing such trash to appear under their
>byline. And you could tell all that without even reading it for
>yourself!

It's a knack.

[Bob Casanova]

On Sun, 08 Dec 2013 11:30:17 -0800, the following appeared
in talk.origins, posted by Jimbo <Jimbol...@nospam.com>:

>On Sun, 08 Dec 2013 11:39:53 -0700, Bob Casanova <nos...@buzz.off>

>wrote:
>

>>On Sat, 07 Dec 2013 18:01:46 GMT, the following appeared in
>>talk.origins, posted by Nick Roberts
>><tig...@orpheusinternet.co.uk>:
>>
>>>In message <onh6a9p4l901u8qml...@4ax.com>
>>> Richard Norman <r_s_n...@comcast.net> wrote:
>>>
>>>[Snip]
>>>

>>>> The subject is not at all whether humans are destroying the ecosystem.
>>>> And the paper is not at all an apologetic for that destruction. The
>>>> simple fact is that the human diet in no way shape or form resembles
>>>> the diet of an apex predator.
>>>

>>>I've not had any training in ecology, but it struck me while reading
>>>this thread that pre-agriculture humans may indeed be apex predators.
>>>Would this be accurate?
>>>
>>>If so, humans may be in the unique position of being an ex
>>>apex predator, not because a different species got better at predation,
>>>but for social reasons.
>>
>>Quite a few of the comments I've read in this thread seem to
>>assume that an apex predator (in fact, a predator in
>>general) is necessarily a carnivore. This doesn't seem to
>>square with the definition of "predator" ("an animal which
>>preys on others"), which only seems to exclude herbivores;
>>bears and humans are both predators, and I'd consider both
>>to be candidate apex predators. Comments?
>

>The term usually refers to 'top' predators which aren't themselves
>prayed upon and which serve to stabilize their ecosystems and keep
>them 'healthy.'

I can see where that comes from, but I'm curious... Is there
an oceanic apex predator? I'd nominate both orcas and large
sharks such as Great Whites, but I can't see how either
stabilizes the ecosystem in any significant way, the way,
for instance, wolf packs do for deer populations or foxes
(and wolves) do for rabbits.

> By that criterion bears usually qualify but humans
>often don't. We haven't physically adapted to a specific ecological
>niche, so we tend to destabilize ecosystems as much or more than we
>stabilize them.

Agreed, with the proviso that non-technological societies
such as traditional Inuit or Bushmen don't tend to
destabilize ecosystems more than any other omnivores such as
bears.

>I don't think being a pure carnivore is a necessary feature. Cats are
>pure carnivores but canids and ursids aren't. Their backteeth are
>adapted both to slicing meat and to grinding vegetation. Felines have
>slicing backteeth with no grinding surface, and their digestive system
>is adapted to a pure meat diet. So being an apex predator refers to
>the role in an ecological community rather than to the percentage of
>meat intake.

Agreed, and my initial point.

>As for human beings, the ecological term just doesn't apply to the
>species as a whole because different groups can figure out different
>ways to live that incorporate different sets of ecological
>interactions.

True, but if a particular society adapts to a particular
ecosystem, and doesn't attempt to change that ecosystem (see
above for two examples) I'd argue that they qualify as well
as any species for the term "apex predator".

> It's like how the laws of physics break down when
>attempts are made to apply them to the center of black holes. Some of
>the laws of ecology just don't apply to our own species in the same
>way they apply (more or less) to every other sort of living thing.

In general, no, we don't. But as I commented above, I
believe that's a result of culture rather than of biology
per se.

Anyway, thanks for the response; again, I've learned
something far outside my field.
--

Bob C.

"The most exciting phrase to hear in science,
the one that heralds new discoveries, is not
'Eureka!' but 'That's funny...'"

- Isaac Asimov

[Bob Casanova]

On Sun, 08 Dec 2013 13:16:13 -0700, the following appeared
in talk.origins, posted by Richard Norman
<r_s_n...@comcast.net>:

I assume the inclusion of "carnivores" was an error, since
I've never seen anything which restricts a predator to the
consumption of carnivores.

>Since there are many organisms at trophic level 3 to 4, he don't
>qualify. Also, before the advent of modern technology (and still
>continuing today in many parts of the world) there are plenty of
>predators that regularly take humans as food.

Agreed, but I don't think any predators, as a species, rely
on humans as food the way wolves rely on deer and rabbits
(and mice). Aberrant individuals, yes, but humans tend to
remove such individuals when they appear.

> Again, we fail to

>qualify as unambiguous apex predators.

Thanks for the response, which was *far* more detailed and
informative than I expected.

[Bob Casanova]

On Mon, 9 Dec 2013 10:46:34 +1100, the following appeared in
talk.origins, posted by jo...@wilkins.id.au (John S.
Wilkins):

>Nominated as being very informative.

Seconded.

>> Since there are many organisms at trophic level 3 to 4, he don't
>> qualify. Also, before the advent of modern technology (and still
>> continuing today in many parts of the world) there are plenty of

>> predators that regularly take humans as food. Again, we fail to

>> qualify as unambiguous apex predators.

[Jimbo]

On Mon, 09 Dec 2013 13:38:00 -0700, Bob Casanova <nos...@buzz.off>

it works pretty much the same in the oceans as on land:

https://www.sharksavers.org/en/education/the-value-of-sharks/sharks-role-in-the-ocean/

Probably killer whales are similar, but I don't think they've been as
extensively studied.

>> By that criterion bears usually qualify but humans
>>often don't. We haven't physically adapted to a specific ecological
>>niche, so we tend to destabilize ecosystems as much or more than we
>>stabilize them.
>
>Agreed, with the proviso that non-technological societies
>such as traditional Inuit or Bushmen don't tend to
>destabilize ecosystems more than any other omnivores such as
>bears.

Perhaps. But there's evidence that Australian aboriginals changed the
landscape by their deliberate use of fire, and may have hunted some
species to extinction. Similarly the Maori killed off the nine species
of moa, probably through combined hunting and habitat destruction.
Eventually the altered ecosystems became somewhat stable, but
initially humans have tended to be very destructive to existing
ecosystems. We're not unique in that respect of course, but humans
have been able for tens of thousands of years to penetrate into and
adapt to a much wider variety of habitats than any other predatory
species.

>>I don't think being a pure carnivore is a necessary feature. Cats are
>>pure carnivores but canids and ursids aren't. Their backteeth are
>>adapted both to slicing meat and to grinding vegetation. Felines have
>>slicing backteeth with no grinding surface, and their digestive system
>>is adapted to a pure meat diet. So being an apex predator refers to
>>the role in an ecological community rather than to the percentage of
>>meat intake.
>
>Agreed, and my initial point.
>
>>As for human beings, the ecological term just doesn't apply to the
>>species as a whole because different groups can figure out different
>>ways to live that incorporate different sets of ecological
>>interactions.
>
>True, but if a particular society adapts to a particular
>ecosystem, and doesn't attempt to change that ecosystem (see
>above for two examples) I'd argue that they qualify as well
>as any species for the term "apex predator".

Me too. Richard might argue that point, but I agree with you on this
issue.

>> It's like how the laws of physics break down when
>>attempts are made to apply them to the center of black holes. Some of
>>the laws of ecology just don't apply to our own species in the same
>>way they apply (more or less) to every other sort of living thing.
>
>In general, no, we don't. But as I commented above, I
>believe that's a result of culture rather than of biology
>per se.

But it's part of our biology to create and maintain cultures. Cultural
anthropologists used to argue that humans lack instincts, but I think
there's plenty of evidence that we have innate abilities and
behavioral predispositions that could be regarded as instinctive and
that are central to our ability to create and maintain new ways of
life with their associated ecologies.

>Anyway, thanks for the response; again, I've learned
>something far outside my field.

Yeah, I learn stuff on TO also, though I don't participate much.

[Richard Norman]

On Mon, 09 Dec 2013 13:44:07 -0700, Bob Casanova <nos...@buzz.off>

Just to be punctiliously correct --

I DID mean prey on carnivores because that puts the predator on a
higher trophic level. A predator at the "top of the food chain", as
apex predators must be, feed at a rather higher trophic level than one
that preys primarily on herbivores. Also whether humans are the
primary food or merely an opportunistic one does not alter whether we
fail to be apex predators.

[James Beck]

On Sun, 08 Dec 2013 15:11:49 -0700, Richard Norman
<r_s_n...@comcast.net> wrote:

>On Sun, 08 Dec 2013 14:16:08 -0700, James Beck <jdbec...@yahoo.com>
>wrote:
>
>>On Sun, 08 Dec 2013 14:04:36 -0700, Richard Norman
>><r_s_n...@comcast.net> wrote:
>>
>>>On Sun, 08 Dec 2013 14:02:22 -0700, James Beck <jdbec...@yahoo.com>
>>>wrote:
>>>

>>>>>>>> The subject is not at all whether humans are destroying the ecosystem.
>>>>>>>> And the paper is not at all an apologetic for that destruction. The
>>>>>>>> simple fact is that the human diet in no way shape or form resembles

>>>>>>>> the diet of an apex predator. Because humans are guilty of some truly
>>>>>>>> grievous faults you seem to argue that nobody should pay any attention
>>>>>>>> to any other subject because that is just another way of minimizing or
>>>>>>>> justifying those faults.
>>>>>>>>
>>>>>>>
>>>>>>> The subject is what are apex predators. Humans obviously qualify in the
>>>>>>> only ways that matter. It isn't so much about ecology as ridiculous
>>>>>>> classification. It is as stupid as if cladists had concentrated on fins
>>>>>>> and body shape so that they could classsify whales as fish and miss what
>>>>>>> whales actually are. Reality is that simple in this case. Why can
>>>>>>> humans affect the ecology so drastically? If you ignore reality what do
>>>>>>> you end up with? Whales as fish.
>>>>>>
>>>>>> Possibly you should read the paper to see what the actual subject
>>>>>> matter is.
>>>>>>
>>>>>
>>>>>The subject matter was trophic level which obviously is not a good
>>>>>indicator of what an apex predator is. Just like fins and body shape
>>>>>aren't the defining attribute of fish or whales.
>>>>

>>>>Good for you. I'm surprised that PNAS would take such a crappy paper.
>>>
>>>Have either you or Ron actually read the paper to see whether it is
>>>really crappy?
>>
>>The real question is why you can't tell at a glance that it's crap.
>
>Generally I try to read and understand the content before making such
>judgements.
>
>Can you provide cogent arguments based on the actual content of the
>paper to indicate that it is crap?

Behaving like poor people has a high correlation with being poor. So
what? We observe empirically that as real income rises demand for meat
increases while direct demand for cereals falls. Cereals are classic
inferior goods. This phenomenon has been understood for nearly a
century. There is nothing new there.

The quality level of the paper is roughly what you expect from an MBA
or econ masters student group project, i.e., a data dump combined with
a bit of short-term, instrumental thinking (sometimes earlier; TSA is
usually sophomore or junior level econ, though the grad students are
more likely to do a data dump). Assuming that the World Bank
economists read this paper they are undoubtedly astonished ... that
PNAS would accept this crap. As is, it probably wouldn't be accepted
by a third tier economics journal, though it's easier to fool editors
at that level. Since the 1980s, you'll find a fair amount of mediocre
economic work written by ecologists published at that tier.

The metrics of the paper are old hat. Why would anyone bother using
dynamic time warping for such a tiny dataset in order to find a known
relationship anyway? Then again, if you need to justify using a
dynamic clustering tool, it might be best to search for something we
already know. In any event, the tool is 20 years old, the World Bank
data has been pretty deeply dredged, and the relationship was already
very well known. What is their contribution? Evidently, it was new to
someone at PNAS, but it hasn't really been new for a long time. In any
event, one need only look at the charts to know that meat consumption
increases with income, not time as asserted in the abstract.

In addition, they didn't do a very thorough lit search, even in
ecological economics, where NSF-funded, neo-Ricardian embodied energy
value theory is now almost thirty years old. It would say that the
results in Bonhommeau, et al are consistent with the hypothesis that
H. sapiens is a massively overpopulated, omnivorous, apex consumer
eating *down* the food chain. Possibly Ron O knows that, or maybe his
intuition is just better than yours.

If, as you assert elsethread, the paper is only about what different
human populations eat, why not just present an average local menu?
That's a rhetorical question. Obviously, doing it this way lets them
pretend to be doing both ecology and economics, while saying nothing
new or insightful about either.

[RonO]

And for the last time the paper makes trophic level comparisons and
where do they place humans? Not a good designation is it? Not a good
or accurate evaluation of where we stand in comparison to other animals.

Ron Okimoto

Ron Okimoto

[Bob Casanova]

On Mon, 09 Dec 2013 13:33:42 -0800, the following appeared

Interesting and informative; thanks.

>Probably killer whales are similar, but I don't think they've been as
>extensively studied.

I admit I was thinking more of orcas than sharks with my
comment, since the main prey of orcas (from what I've read)
are seals, themselves mostly (entirely?) carnivorous. But
there's probably a similar relationship there.

>>> By that criterion bears usually qualify but humans
>>>often don't. We haven't physically adapted to a specific ecological
>>>niche, so we tend to destabilize ecosystems as much or more than we
>>>stabilize them.
>>
>>Agreed, with the proviso that non-technological societies
>>such as traditional Inuit or Bushmen don't tend to
>>destabilize ecosystems more than any other omnivores such as
>>bears.
>
>Perhaps. But there's evidence that Australian aboriginals changed the
>landscape by their deliberate use of fire, and may have hunted some
>species to extinction. Similarly the Maori killed off the nine species
>of moa, probably through combined hunting and habitat destruction.
>Eventually the altered ecosystems became somewhat stable, but
>initially humans have tended to be very destructive to existing
>ecosystems. We're not unique in that respect of course, but humans
>have been able for tens of thousands of years to penetrate into and
>adapt to a much wider variety of habitats than any other predatory
>species.

I think that's a major point; humans not only adapt the
environment but adapt themselves to a far wider range of
environments than nearly any other species, giving us a
wider range of opportunities to do damage.

Agreed. I suspect the "humans have no instincts" idea comes
from the same mindset that proclaims that humans aren't
animals; we're "different" and "better" than mere animals.

>>Anyway, thanks for the response; again, I've learned
>>something far outside my field.
>
>Yeah, I learn stuff on TO also, though I don't participate much.

[Bob Casanova]

On Mon, 09 Dec 2013 16:08:46 -0700, the following appeared

Does that apply if there are no other predators in that
environment? Or can there be two apex predators in a given
environment if they occupy different niches and don't
interact?

> Also whether humans are the
>primary food or merely an opportunistic one does not alter whether we
>fail to be apex predators.

So, the fact that we may occasionally be prey to other
predators doesn't mean we couldn't also be apex predators?
Does that apply to *all* putative apex predators, including
those which may themselves fall prey to "lesser" predators
occasionally?

All of this seems to be as much a "gray area" as the concept
of "species", a concept of which no two biologists seem to
have the same definition.

[Richard Norman]

On Tue, 10 Dec 2013 10:47:18 -0700, Bob Casanova <nos...@buzz.off>

I thought I already went through this with my long screed about
ecology. I don't have my ecology books or my contact with my
ecologist former colleagues with me where I winter but here goes
again:

The details of exactly who is an apex predator is not really that
important and the details of exactly how to define one is similarly
not that important. What is important for ecology in general is
understanding the various trophic levels at which any particular
animal feeds and in the notion of "keystone species" which play
particular roles in altering, often maintaining, the ecological
structure of the community. In any one particular ecosystem, of
course, what is important is exactly who feeds on whom and how that
feeding influences the population of each component of the community.

The notion of "apex" predator mixes three different notions. One, the
one I have considered dominant, is that the apex predator is at the
top of the food chain. Even Wikipedia, which most definitely mixes
the concepts, states "In this context, "apex predator" is usually
defined in terms of trophic dynamics . Apex predator species occupy
the highest trophic level(s)" and "One study of marine food webs
defined apex predators as greater than trophic level four." That is
the notion used by the paper which opened this thread. It is a very
legitimate way of using the term "apex predator" even if you prefer to
emphasize the other notions.

A second notion is that of stabilizing communities. Wikipedia inserts
this between the two quotes I gave: "and have a crucial role in
maintaining the health of their ecosystems". That is usually true but
is not consistently applied because the notion of "keystone species"
is better and cleaner, not being confounded with other meanings. To
illustrate the confusion, Wikipedia says in the article on "apex
predator" that : "Keystone species are apex predators within
functional groups". However in the article on keystone species it
says: "These creatures need not be apex predators."

It is this second notion that people in this news group have focussed
on as The Key part of the definition. I strongly disagree with that
interpretation but so be it.

A third notion is that nobody preys on the apex predator. That notion
derives from the fact that the top of the food chain is usually the
"toughest guy on the block." However Wikipedia then goes on to list
animals that are not preyed upon simply because they have very effect
defenses without any regard to their position in the food chain or
their effect on the ecological community. That seems to be the
component that you are now interested in.

So it is best not to pay too much attention to what is or is not an
apex predator but rather pay more attention to the important ecology
that your favorite species plays.

And, just to repeat, the paper is NOT about how humans interact with
the biological community but rather deals with a quantitative measure
of indicating one important aspect of socioeconomic development in
different countries of the world.

[Jimbo]

On Tue, 10 Dec 2013 10:38:34 -0700, Bob Casanova <nos...@buzz.off>

Some populations definitely feed on young gray calves during the
gray's annual migration up the coast of California. It doesn't seem
likely they'd have much impact on gray whale populations if this kind
of ambush predation only occurs once a year during the migration. But
many adult grays bear scars from orca attacks. Maybe some of those
attacks were on adult whales.

http://www.adn.com/2013/05/05/2891755/orcas-ambush-alaska-bound-gray.html

These are far-ranging 'transient' orca pods making the ambush attacks.
The whales belonging to these populations may be a different species
or subspecies from the fish-eating orcas living in established
territories up North. Or maybe it's just different populations with
different cultural traditions and techniques. Maybe some groups are
like the nomadic Plains Indians following the bison while other
populations consist of more gentle and settled fisher-whales. I don't
think that question has yet been answered.

[Jimbo]

The question could be reframed as "Is _Homo_sapiens_ a keystone
species. But that's ambiguous, too. The Australian aboriginals would
qualify as a keystone 'quasi-species' since, by their practice of
burning off brush, they controlled the structure of an ecological
community. They reduced the tree cover and moved the ecosystem toward
more of a grassland biome condition. The Semang, on the other hand,
functioned as woodland hunters and gatherers and, so far as I can see,
had very little impact upon the nature of the forest. So, are we a
keystone species or not? It depends on what population you're looking
at.

>It is this second notion that people in this news group have focussed
>on as The Key part of the definition. I strongly disagree with that
>interpretation but so be it.

Then how would you apply the concept of keystone species to
_Homo_sapiens_?

>A third notion is that nobody preys on the apex predator. That notion
>derives from the fact that the top of the food chain is usually the
>"toughest guy on the block." However Wikipedia then goes on to list
>animals that are not preyed upon simply because they have very effect
>defenses without any regard to their position in the food chain or
>their effect on the ecological community. That seems to be the
>component that you are now interested in.
>
>So it is best not to pay too much attention to what is or is not an
>apex predator but rather pay more attention to the important ecology
>that your favorite species plays.

But what is the role of _Homo_sapiens_ in *any* ecosystem? What is our
fundamental and underlying ecology? You won't get a clue from the
paper under discussion. You'll only get a get what seems to be a
rather superficial survey of the changes occurring in the diets of
agro-industrial societies.

>And, just to repeat, the paper is NOT about how humans interact with
>the biological community but rather deals with a quantitative measure
>of indicating one important aspect of socioeconomic development in
>different countries of the world.

I think everybody gets that, but what does the paper tell us that we
don't already know?

[Richard Norman]

On Tue, 10 Dec 2013 11:55:40 -0800, Jimbo <Jimbol...@nospam.com>

No, you don't get a clue from understanding our fundamental and
underlying ecology from the paper because that is not what the paper
is about. As to whether there is any value in the paper, it seems our
opinions are rather already firmly settled on this matter and that
everything has already been said. There is no need to rehash it once
again.

And as to a human role as "keystone species", since humans interact
with natural biological ecosystems in a distincty non-biological way
the notion does not readily apply. If you define the term as "having
an impact out of proportion to its abundance" you still have problems
because we have both enormous impact and enormous abundance.

[Jimbo]

On Tue, 10 Dec 2013 13:22:23 -0700, Richard Norman

At any rate we've established something here. None of these concepts -
apex predator, keystone species, and trophic level, can be used to
characterize _Homo_sapiens_ in the same way that they can be applied
to other species. Yet human populations can function as quasi-keystone
species and apex predators. That may tell us more about human ecology
than does a 'HTL' that shifts with every population studied.

[Richard Norman]

On Tue, 10 Dec 2013 12:48:40 -0800, Jimbo <Jimbol...@nospam.com>

Please cut the crap. The purpose of the study was to get a measure
that WOULD show changes between countries and within one country with
time. It is NOT about "human ecology" in the way you want it to be.

[Jimbo]

On Tue, 10 Dec 2013 13:55:05 -0700, Richard Norman

I know, but they invited the criticism by employing a term that does
apply to the ecology of non-human species. If they'd simply stuck to
graphing the shifting trophic level of Chinese or Indian Villagers,
and dispensed with the whole 'HTL' thing, there wouldn't have been the
expectation that their metric could be applied to the species as a
whole. Or they could have done as James Beck suggested and presented
an average local menu. It's ecologically significant that
_Homo_sapiens_ has no single trophic level. If they had pointed this
out, it might have made for a less trivial paper.

But you're right that we're just rehashing things now.

[Darwin123]

On Friday, December 6, 2013 8:41:31 AM UTC-5, Ron O wrote:

> Maybe they will start calling humans Alpha Apex Omnivores. We eat the
> other apex predators and just about anything else. What can you call a
> species that eats vegemite, and make expensive beverages from the poop
> of wild cats.

A parasite. In your examples, we don't immediately wipe out the thing we eat. We either raise or steal from the organisms that we live off of.


I think Homo sapiens in technical societies (which includes agricultural and husbandry societies) are really apex parasites. We are not predators at all. Only hunter gatherers can claim to be true predator.

Predators by definition kill their prey immediately before or while
they eat them. They don't often leave survivors. Parasites can live
inside the body (endoparasites), on the body (ectoparasites) or even
outside the body (exoparasites?).

Biologists use the word parasite to include a broad spectrum of organisms
that don't kill their prey immediately. Medical doctors often restrict the
word to protozoa and animals that don't kill their prey immediately. For
purposes of discussion, I am using the more general definition used by biologists.

The biological definition is broad. Thus, I am including bacteria and
viruses. I am also including amazon ants. Amazon ants are ants that enslave other ants. I am including mosquitos and vampire bats because they leave
their prey alive. Not to mention leaf cutter ants that eat fungi that they

Homo sapiens var tech raises animals and plants to live off of. A rancher, even one using ancient technology, raises the animal which is eaten.
A farmer grows the grain and fruit that he eats. Both are intimately
involved in the life cycle of their prey. They have an interest in prolonging
the life of their prey.

A human hunter kills his prey before he eats it. He has no vested interest involving him with the life cycle of his prey. He interacts with his prey a
very short time. Thus, the selection pressure on a hunter is much different
than the selection pressure on a cowboy or shepherd.

The evolution of parasites is sometimes very different from the evolution
of the corresponding predator. In a way, humans are at a transition point
between being predators and being parasites. Our biggest challenge now isn't
competition with predators. It is competition with other parasites. Epidemics
are far more threatening to us than carnivores.

Our parasitism is likely to increase. It used to be that the fish we
ate came from wild populations. Now, much of the fish we eat comes from
farms. As fishing populations get depleted, we may come to depend entirely
on fish farms. "Fishermen" are turning from being hunters to being fish
parasites.

Homo sapiens: The ultimate parasite! It may not be as bad as it sounds.

[eridanus]

El mi�rcoles, 11 de diciembre de 2013 03:08:08 UTC, Darwin123 escribi�:

a perfect commentary. I loved it.
eridanus

[eridanus]

El mi�rcoles, 11 de diciembre de 2013 03:08:08 UTC, Darwin123 escribi�:

let me post here two paragraphs from the book "War before Civilization",
from Lawrence H. Keeley, page 100, Chap 7, tittled "Profits and Losses of Primitive War".

By far the most common and widely distributed war trophy was the head or
skull of an enemy. The custom of taking heads is recorded from many
cultures in New Guinea, Oceania, North America, South America and Ancient
Western Europe. The popularity of this practice is probably explained by
the obvious fact that the head is the most individual part of the body.
For warriors the world over, the prestige or spiritual power accruing to
the victor depended on the personal qualities and reputations of his
victims. More than any other body part, the head of a vanquished foe was
an unequivocal token of the individual that had been overcome. Such
trophies were so representative of the individual from whom that had been
taken that victors often spoke to their trophy heads by name, reviling
and exulting over them. For example, an early missionary in New Zealand
heard a Maori warrior taunting the preserved head of an enemy chief in
the following fashion:
"You wanted to run away did you? but my meri (war club) overtook you; and
after you were cooked, you made food for my mouth. And where is your
father? He is cooked; and where is your brother? he is eaten; and where
is your wife? there she sit, a wife for me; and where are your children?
They are there, with loads on their backs, carrying food, as my slaves."

This summarizes a little that humans can be in part predators, and in part
parasites of other human beings, as well parasites of some domestic
animals.

Eridanus

[Richard Norman]

This is an interesting metaphoric use of the word "parasite" which is
commonly used in ordinary language. It doesn't really conform to the
biological definition though which requires the two species to live in
close association (symbiosis) far tighter than what is described. The
definition is broad but not that much. The metaphoric usage does
involve the exploitation of one species by another and is accurate and
appropriate.

Grazing is the term for feeding distinct from parasitism or predation
where the target is not killed. In many cases plants "deliberately"
offer parts of their bodies or secretions to animals as food in
exchange from some service the animal provides such as distributing
pollen or seeds. Some Acacias even provide nourishment and housing
for a species of ant that protects the tree from herbivores. Animals
have a growth pattern quite different from plants so "grazing" on
animals is rare. However parrotfish do graze on coral in addition to
feeding on the algae that overgrow the coral. The individual polyps
are killed but not the colony.