A new classifaction of dinosaurs

[RSNorman]

The current issue of Nature has a paper: "A new hypothesis of
dinosaur relationships and early dinosaur evolution" by Matthew G.
Baron, David B. Norman & Paul M. Barrett
Nature 543, 501–506 (23 March 2017) doi:10.1038/nature21700
http://www.nature.com/nature/journal/v543/n7646/full/nature21700.html

The abstract reads:

For 130 years, dinosaurs have been divided into two distinct
clades—Ornithischia and Saurischia. Here we present a hypothesis for
the phylogenetic relationships of the major dinosaurian groups that
challenges the current consensus concerning early dinosaur evolution
and highlights problematic aspects of current cladistic definitions.
Our study has found a sister-group relationship between Ornithischia
and Theropoda (united in the new clade Ornithoscelida), with
Sauropodomorpha and Herrerasauridae (as the redefined Saurischia)
forming its monophyletic outgroup. This new tree topology requires
redefinition and rediagnosis of Dinosauria and the subsidiary
dinosaurian clades. In addition, it forces re-evaluations of early
dinosaur cladogenesis and character evolution, suggests that
hypercarnivory was acquired independently in herrerasaurids and
theropods, and offers an explanation for many of the anatomical
features previously regarded as notable convergences between theropods
and early ornithischians.

Given the usual progress (devolution) of discussions here on t.o., I
would suggest that anyone seriously interested in discussing the real
science of this change move over to sbp (sci.bio.paleontoloty)

[Burkhard]

boo, you clickbaiter. I thought "dinosaur relationships" would be about
their sex life

[jillery]

On Wed, 22 Mar 2017 13:18:23 -0700, RSNorman <r_s_n...@comcast.net>
wrote:

Is there anything you would recommend posted to T.O.?
To follow your advice is to let the terrorists win.
--
This space is intentionally not blank.

[jillery]

On Wed, 22 Mar 2017 17:14:52 -0400, jillery <69jp...@gmail.com>
wrote:

BTW, I have watched the posts of certain parties on sbp, and have not
noticed a substantial difference in their behavior. Apparently your
mileage varies.

[RSNorman]

On Wed, 22 Mar 2017 17:14:52 -0400, jillery <69jp...@gmail.com>
wrote:

I would be happy to see a serious discussion of the science on this
topic here on t.o. Would you like to start one?

[jillery]

On Wed, 22 Mar 2017 15:04:40 -0700, RSNorman <r_s_n...@comcast.net>

Since you asked, I am unqualified to start a discussion of such a
technical subject as the relative merits of different cladograms. At
best, I am qualified to comment only on some peripheral and general
issues which might involve cladistics.

OTOH you have already started discussion on this topic, so your
question above implies you think your post wasn't a serious one.

OTGH it would be incorrect if anybody misread your comments and
thought you claimed I hadn't already started numerous serious topics
in T.O.

Of course, I can almost as easily read sbp, but that's not relevant to
the point. You explicitly discouraged discussing this topic here, and
encouraged its transfer to another group. And just yesterday, in
reply to me, you asked a rhetorical question which implied you thought
that topic should be ended as well.

I realize it's easier to complain than provide constructive criticism.
I regret if you feel I put that burden on you unfairly. But you are on
record for eliminating topics from T.O. IMO my question to you above
is fair and reasonable and well-directed and deserves a direct
response, which you did not provide. So, instead of recommending what
otherwise on-topic topics should be removed from T.O., what topics
would you recommend be included?

[RSNorman]

On Thu, 23 Mar 2017 01:19:36 -0400, jillery <69jp...@gmail.com>

I am very happy to see serious discussion here only to be disappointed
all too frequently (but not always) about how everything so quickly
degenerates. The simple fact is that our current exchange is not at
all about how dinosaurs should be classified but rather is entirely
within what t.o. usually runs on about.

You may respond as you wish but I will participate further only if the
subject is dinosaurs.

[Rolf]

"RSNorman" <r_s_n...@comcast.net> skrev i melding
news:qlo6dchpaukmmqofk...@4ax.com...

> On Thu, 23 Mar 2017 01:19:36 -0400, jillery <69jp...@gmail.com>
> wrote:
>
>>On Wed, 22 Mar 2017 15:04:40 -0700, RSNorman <r_s_n...@comcast.net>
>>wrote:
>>
>>>On Wed, 22 Mar 2017 17:14:52 -0400, jillery <69jp...@gmail.com>
>>>wrote:
>>>
>>>>On Wed, 22 Mar 2017 13:18:23 -0700, RSNorman <r_s_n...@comcast.net>
>>>>wrote:
>>>>
>>>>>The current issue of Nature has a paper: "A new hypothesis of
>>>>>dinosaur relationships and early dinosaur evolution" by Matthew G.
>>>>>Baron, David B. Norman & Paul M. Barrett

>>>>> Nature 543, 501-506 (23 March 2017) doi:10.1038/nature21700

>>>>> http://www.nature.com/nature/journal/v543/n7646/full/nature21700.html
>>>>>
>>>>>The abstract reads:
>>>>>
>>>>>For 130 years, dinosaurs have been divided into two distinct

>>>>>clades-Ornithischia and Saurischia. Here we present a hypothesis for

Isn't that what t.o. was created for?
Not the most exciting forum, but as long as it serves its purpose ...

[Ernest Major]

On 22/03/2017 20:18, RSNorman wrote:
> The current issue of Nature has a paper: "A new hypothesis of
> dinosaur relationships and early dinosaur evolution" by Matthew G.
> Baron, David B. Norman & Paul M. Barrett
> Nature 543, 501–506 (23 March 2017) doi:10.1038/nature21700
> http://www.nature.com/nature/journal/v543/n7646/full/nature21700.html
>

The article is paywalled; you can get the first page at

http://www.readcube.com/articles/10.1038/nature21700elsewhere

See also


https://blogs.scientificamerican.com/tetrapod-zoology/ornithoscelida-rises-a-new-family-tree-for-dinosaurs/


--
alias Ernest Major

[*Hemidactylus*]

Link us a paywalled article providing abstract with no opinion of your own
except to disparage this group. Then tell us instead to go over to a group
that is the personal hangout of a certain someone I would much rather avoid
especially given this is a favorite topic of theirs. I'd rather sift
through Wise TibetanMonkey threads. Less stressful.

What impact to bird classification if you don't mind slumming it out here
for a sec?

What's paleontoloty? It drives my spell checker crazy.

[*Hemidactylus*]

You see that's just the sort of prurient thread dilution we have come to
expect from you. Keep up the good work 🙃

[jillery]

On Thu, 23 Mar 2017 09:25:17 +0100, "Rolf" <rolf.a...@gmail.com>
wrote:

An irony here is the one who started the devolution of this discussion
stares at rnorman in the mirror. Whatever T.O. was created for, he
uses it to project his own responsibility for the digressions he
complains about onto others. This is as serious and relevant an issue
to T.O. as dinosaur cladistics, even if not officially recognized.

[J. J. Lodder]

*Hemidactylus* <ecph...@allspamis.invalid> wrote:

> Burkhard <b.sc...@ed.ac.uk> wrote:
> > RSNorman wrote:
> >> The current issue of Nature has a paper: "A new hypothesis of
> >> dinosaur relationships and early dinosaur evolution" by Matthew G.
> >> Baron, David B. Norman & Paul M. Barrett

> >> Nature 543, 501506 (23 March 2017) doi:10.1038/nature21700

> >> http://www.nature.com/nature/journal/v543/n7646/full/nature21700.html
> >>
> >> The abstract reads:
> >>
> >> For 130 years, dinosaurs have been divided into two distinct

> >> clades-Ornithischia and Saurischia. Here we present a hypothesis for

> >> the phylogenetic relationships of the major dinosaurian groups that
> >> challenges the current consensus concerning early dinosaur evolution
> >> and highlights problematic aspects of current cladistic definitions.
> >> Our study has found a sister-group relationship between Ornithischia
> >> and Theropoda (united in the new clade Ornithoscelida), with
> >> Sauropodomorpha and Herrerasauridae (as the redefined Saurischia)
> >> forming its monophyletic outgroup. This new tree topology requires
> >> redefinition and rediagnosis of Dinosauria and the subsidiary
> >> dinosaurian clades. In addition, it forces re-evaluations of early
> >> dinosaur cladogenesis and character evolution, suggests that
> >> hypercarnivory was acquired independently in herrerasaurids and
> >> theropods, and offers an explanation for many of the anatomical
> >> features previously regarded as notable convergences between theropods
> >> and early ornithischians.
> >>
> >> Given the usual progress (devolution) of discussions here on t.o., I
> >> would suggest that anyone seriously interested in discussing the real
> >> science of this change move over to sbp (sci.bio.paleontoloty)
> >>
> > boo, you clickbaiter. I thought "dinosaur relationships" would be about
> > their sex life
> >
> You see that's just the sort of prurient thread dilution we have come to

> expect from you. Keep up the good work ?

Well, how did Diploducus do it?

Jan

[Burkhard]

Darling, it is absolutely sho-cking!. I've just heard, and don't tell
anyone, that Andrew, that nice Diploducus Carnegii boy, you know, from
the Pennsylvania Carnegies, EXCELLENT family, though they have this
nephew who is quite frankly a bit potty, found religion and went on a
haji or some such...anyhow, where was I.. ah yes, Andrew is now going
out with this really dubious character, a Diploductus lacustris, would
you believe it!!!! She is WAY too young and immature for him anyone
says, and if you look at her snout, I could not be surprised if there
was some Camarasaurus blood in the family tree somewhere. And you KNOW
what THEY are like...

[RSNorman]

On Thu, 23 Mar 2017 05:52:00 -0500, *Hemidactylus*
<ecph...@allspamis.invalid> wrote:

>RSNorman <r_s_n...@comcast.net> wrote:
>> The current issue of Nature has a paper: "A new hypothesis of
>> dinosaur relationships and early dinosaur evolution" by Matthew G.
>> Baron, David B. Norman & Paul M. Barrett

>> Nature 543, 501?506 (23 March 2017) doi:10.1038/nature21700

>> http://www.nature.com/nature/journal/v543/n7646/full/nature21700.html
>>
>> The abstract reads:
>>
>> For 130 years, dinosaurs have been divided into two distinct

>> clades?Ornithischia and Saurischia. Here we present a hypothesis for

I have just been reminded by Rolf that the purpose of this news group
was to confront the crazies and so leave groups like the sci.bio set
for serious scientific discussion. That a particular individual you
dislike does post to sci.bio.paleontoloty (however spelled) is
irrelevant, there does occur more orderly discussion there. Also on
that news group I posted how you could obtain a copy of the full text.

There are now sufficient secondary sources about this subject to
satisfy anyone with a real interest. As to bird classification the
paper has no specific comments since the real subject is how to locate
the theropods amongst the other "dinosaurs". But it does specifically
define the clade Theropoda to include the species Passer domesticus,
the House Sparrow, so we know that the "true" birds must still remain
right in their accepted home base even as that base has shifted.

The real irony is that for well over a century the dinosaurs were
divided into the "bird-hipped" (Ornithischians) vs. the
"lizard-hipped" (Saurischia) even though the real birds were long
thought to come from the lizard-hipped group. In other words, the
attribution of the names of the two groups to "birds" and 'lizards"
was long known to be incorrect. Now it turns out that moving the
Theropoda might restore some of the validity of those ancient names.

[jillery]

On Thu, 23 Mar 2017 12:00:33 -0700, RSNorman <r_s_n...@comcast.net>
wrote:

I note your apparent change of mind about the conditions for which you
would participate further. Or is it you don't mean your replies to be
taken serious?

[*Hemidactylus*]

So birds are still dinosaurs just affiliated differently than expected if
these results stand in the long term?

>
> The real irony is that for well over a century the dinosaurs were
> divided into the "bird-hipped" (Ornithischians) vs. the
> "lizard-hipped" (Saurischia) even though the real birds were long
> thought to come from the lizard-hipped group. In other words, the
> attribution of the names of the two groups to "birds" and 'lizards"
> was long known to be incorrect. Now it turns out that moving the
> Theropoda might restore some of the validity of those ancient names.
>

And the Bulldog has regained some post-humous status.

https://en.m.wikipedia.org/wiki/Ornithoscelida

"Baron and colleagues used this opportunity to create a formal definition
for Huxley's old name Ornithoscelida, as the group containing theropods and
ornithischians, "

[*Hemidactylus*]

Well at least the upshot is that Thomas Huxley's Ornithoscelida might very
well fare better than his Bathybius haeckelii brainfart. When recently
reading the Bulldog's book on Hume there were times he seemed too critical
of my hero and I thought "Weren't you the jackass that had a bad idea about
sea slime?".

https://en.m.wikipedia.org/wiki/Bathybius_haeckelii

[RSNorman]

On Thu, 23 Mar 2017 18:09:45 -0500, *Hemidactylus*

What goes around comes around. The bird-ischian vs. lizard-ischian
division came in 1888, some 19 years after Huxley's naming which, of
course, did not deal specifically with hips.

[RSNorman]

That Huxley publicly recanted and admitted error only 11 years after
his original announcement does not do him discredit. Rather quite the
opposite in my view.

A similar thing happened in neurobiology. There was a long standing
argument about whether synaptic transmission was a direct electrical
event or whether there was a chemical intermediary. The proponents of
the two views were known as "sparks" vs. "soups". JC Eccles, a
prominent neurobiologist, was an adamant and very vocal spark. However
in 1951 he conducted an experiment using the new tool of
microelectrode recording that could definitively distinguish, in true
Popperian style, between electrical and chemical transmission. It
turned out to be chemical. As Eccles himself describes it "I went to
England in January 1952 carrying the news of my belated conversion,
and of course with all the enthusiasm of a neophyte. There was a paper
to the Physiological Society and a fascinating Discussion Meeting of
the Royal Society."
THE SYNAPSE: From Electrical to Chemical Transmission
Ann. Rev. Neurosci. 1982. 5:325-39
I believe Eccles was a dedicated spark for much more than 11 years.

Some ten years after this incident I heard as a student from a number
of people that Eccles' announcement of his conversion at the meeting
was greeted with much amusement, applause and general good cheer.

See also
Eliot S. Valenstein
The War of the Soups and the Sparks: The Discovery of
Neurotransmitters and the Dispute Over How Nerves Communicate.
2006. Columbia University Press: New York. 256p.

[jillery]

On Thu, 23 Mar 2017 21:11:51 -0500, *Hemidactylus*
<ecph...@allspamis.invalid> wrote:

>> taken seriously?

>>
>Well at least the upshot is that Thomas Huxley's Ornithoscelida might very
>well fare better than his Bathybius haeckelii brainfart. When recently
>reading the Bulldog's book on Hume there were times he seemed too critical
>of my hero and I thought "Weren't you the jackass that had a bad idea about
>sea slime?".
>
>https://en.m.wikipedia.org/wiki/Bathybius_haeckelii

Actually, the upshot is the apparent trigger for rnorman's further
participation is not comments posted about dinosaurs, as he claimed,
but is instead comments posted by anyone but me.

[DarwinDoubter]

Here's a more detailed account of that article, since your
cite only includes the abstract.




New study shakes the roots of the dinosaur family tree
Date:
March 22, 2017
Source:
University of Cambridge
Summary:

More than a century of theory about the evolutionary history of
dinosaurs has been turned on its head following the publication of new
research. The work suggests that the family groupings need to be
rearranged, redefined and renamed and also that dinosaurs may have
originated in the northern hemisphere rather than the southern, as
current thinking goes.


The new family tree structure is shown.
Credit: University of Cambridge

More than a century of theory about the evolutionary history of
dinosaurs has been turned on its head following the publication of new
research from scientists at the University of Cambridge and Natural
History Museum in London. Their work suggests that the family groupings
need to be rearranged, re-defined and re-named and also that dinosaurs
may have originated in the northern hemisphere rather than the southern,
as current thinking goes.

For 130 years palaeontologists have been working with a classification
system in which dinosaur species have been placed in to two distinct
categories: Ornithischia and Saurischia. But now, after careful analysis
of dozens of fossil skeletons and tens of thousands of anatomical
characters, the researchers have concluded that these long-accepted
familial groupings may, in fact, be wrong and that the traditional names
need to be completely altered.

The classification of dinosaurs dates back to Victorian times. Dinosaurs
were first recognised as a unique group of fossil reptiles in 1842 as a
result of the work of the anatomist, Professor Richard Owen (who later
went on to found the Natural History Museum in London). Over subsequent
decades, various species were named as more and more fossils were found
and identified. During the latter half of the 19th century it was
realised that dinosaurs were anatomically diverse and attempts were made
to classify them into groups that shared particular features.

It was Harry Govier Seeley, a palaeontologist trained in Cambridge under
the renowned geologist Adam Sedgwick, who determined that dinosaurs fell
quite neatly into two distinct groupings, or clades; Saurischia or
Ornithischia. This classification was based on the arrangement of the
creatures' hip bones and in particular whether they displayed a
lizard-like pattern (Saurischia) or a bird-like one (Ornithischia).

As more dinosaurs were described it became clear that they belonged to
three distinct lineages; Ornithischia, Sauropodomorpha and Theropoda. In
1887 Seeley placed the sauropodomorphs (which included the huge
'classic' dinosaurs such as Diplodocus and Brontosaurus) together with
the theropods (which included T. rex), in the Saurischia. The
ornithischians and saurischians were at first thought to be unrelated,
each having a different set of ancestors, but later study showed that
they all evolved from a single common ancestor.

This new analysis of dinosaurs and their near relatives, published today
in the journal Nature, concludes that the ornithischians need to be
grouped with the theropods, to the exclusion of the sauropodomorphs. It
has long been known that birds (with their obviously 'bird-like' hips)
evolved from theropod dinosaurs (with their lizard-like hips). However,
the re-grouping of dinosaurs proposed in this study shows that both
ornithischians AND theropods had the potential to evolve a bird-like hip
arrangement- they just did so at different times in their history.

Lead author, Matthew Baron, says: "When we started our analysis, we
puzzled as to why some ancient ornithischians appeared anatomically
similar to theropods. Our fresh study suggested that these two groups
were indeed part of the same clade. This conclusion came as quite a
shock since it ran counter to everything we'd learned."

"The carnivorous theropods were more closely related to the herbivorous
ornithischians and, what's more, some animals, such as Diplodocus, would
fall outside the traditional grouping that we called dinosaurs. This
meant we would have to change the definition of the 'dinosaur' to make
sure that, in the future, Diplodocus and its near relatives could still
be classed as dinosaurs."

The revised grouping of Ornithischia and Theropoda has been named the
Ornithoscelida which revives a name originally coined by the
evolutionary biologist, Thomas Henry Huxley in 1870.

Co-author, Dr David Norman, of the University of Cambridge, says: "The
repercussions of this research are both surprising and profound. The
bird-hipped dinosaurs, so often considered paradoxically named because
they appeared to have nothing to do with bird origins, are now firmly
attached to the ancestry of living birds."

For 130 years palaeontologists have considered the phylogeny of the
dinosaurs in a certain way. Our research indicates they need to look
again at the creatures' evolutionary history. This is simply science in
action. You draw conclusions from one body of evidence and then new data
or theories present themselves and you have to suddenly reconsider and
adapt your thinking. All the major textbooks covering the topic of the
evolution of the vertebrates will need to be re-written if our
suggestion survives academic scrutiny."

While analysing the dinosaur family trees the team arrived at another
unexpected conclusion. For many years, it was thought that dinosaurs
originated in the southern hemisphere on the ancient continent known as
Gondwana. The oldest dinosaur fossils have been recovered from South
America suggesting the earliest dinosaurs originated there. But as a
result of a re-examination of key taxa it's now thought they could just
as easily have originated on the northern landmass known as Laurasia,
though it must be remembered that the continents were much closer
together at this time.

Co-author, Prof Paul Barrett, of the Natural History Museum, says: "This
study radically redraws the dinosaur family tree, providing a new
framework for unraveling the evolution of their key features, biology
and distribution through time. If we're correct, it explains away many
prior inconsistencies in our knowledge of dinosaur anatomy and
relationships and it also highlights several new questions relating to
the pace and geographical setting of dinosaur origins."

Story Source:

Materials provided by University of Cambridge. The original story is
licensed under a Creative Commons License. Note: Content may be edited
for style and length.

https://www.sciencedaily.com/releases/2017/03/170322143202.htm

[jillery]

>https://www.sciencedaily.com/releases/2017/03/170322143202.htm

[...]

Your link above is especially helpful, since I'm too cheap to pay even
four dollars to read the body of the OP's cite.

It's not surprising that conclusions about dinosaur relationships
change over time, as more data are collected, and different techniques
are applied to analyze them. To the contrary, it would be surprising
if conclusions remained the same. It's no criticism of earlier
paleontologists that they made a division based on hips, which are
large and so more often preserved. Instead, it would be negligent of
modern paleontologists if they didn't refine older hypotheses.

Jack Horner recently made a similar, if less expansive, paradigm
shift:

<http://www.ted.com/talks/jack_horner_shape_shifting_dinosaurs#t-424947>

Short version: There are fewer ceratopsians than was previously
thought. Instead, most of them are the same genus at different stages
of development.

Horner came to that conclusion in part by looking at growth rings
preserved in fossils. Of course, in order to do that, he had to cut
through the fossils, something previous paleontologists understandably
didn't consider doing to rare specimens.

Here's an opinion on the process of these paradigm shifts:

<http://ewp.cas.nyu.edu/docs/IO/37475/pollockhorns05.pdf>

***************************************
What is true is constantly in flux as we learn more. It is
frightening and sad, yet also enlightening and hopeful, given the
possibilities for what we'll know, and how much we’ll grow, as our
communal grasp of how our universe works continues to expand.
***************************************

[John Stockwell]

Yep. Science advances. Isn't it cool?

-John