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chris thompson

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Apr 29, 2013, 6:06:15 PM4/29/13
to
Hi

At what point can one reliably distinguish between a human embryo and a human embryo?

Chris

Thrinaxodon

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Apr 29, 2013, 6:09:21 PM4/29/13
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On Apr 29, 6:06�pm, chris thompson <chris.linthomp...@gmail.com>
wrote:
> Hi
>
> At what point can one reliably distinguish between a human embryo and a human embryo?
>
> Chris

Is this a serious question?

John Harshman

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Apr 29, 2013, 6:16:24 PM4/29/13
to
On 4/29/13 3:06 PM, chris thompson wrote:
> Hi
>
> At what point can one reliably distinguish between a human embryo and a human embryo?

What's the difference between a duck?

Richard Norman

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Apr 29, 2013, 6:29:34 PM4/29/13
to
I can only image your question is "at what point can one reliably
distinguish an embryo as being human?" One anwer is from
Clifford Grobstein
The early development of human embryos
J Med Philos (1985) 10(3): 213-236
doi:10.1093/jmp/10.3.213
http://www.ncbi.nlm.nih.gov/pubmed/4045331

The abstract says "at the end of the eighth week" but the text says
that from the fifth through the eighth week features increasingly
become recognizably human. Of course molecular biological tests will
determine that an embryo is human even from the one-cell stage.

chris thompson

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Apr 29, 2013, 6:36:48 PM4/29/13
to
ACK human embryo and chick embryo. My bad.

Free Lunch

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Apr 29, 2013, 6:40:54 PM4/29/13
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On Mon, 29 Apr 2013 15:16:24 -0700, John Harshman
<jhar...@pacbell.net> wrote in talk.origins:
Why a duck?

Ron O

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Apr 29, 2013, 7:14:08 PM4/29/13
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On Apr 29, 5:36�pm, chris thompson <chris.linthomp...@gmail.com>
wrote:
If you are asking about mammals and birds it is very early. The chick
embryo develops on the surface of the yolk and so is flat compared to
a placental mammal embryo at very early stages. You can't tell that
the mammal is human until later.

Ron Okimoto

Burkhard

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Apr 29, 2013, 7:30:21 PM4/29/13
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Do you suspect your partner to have an affair with a swan? Zeus was
particularly ..male.. recently

czebat...@gmail.com

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Apr 29, 2013, 7:53:52 PM4/29/13
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No! Viaduct!

gregwrld

John Harshman

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Apr 29, 2013, 7:54:55 PM4/29/13
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Hmmm. I think that at the one-cell stage a molecular test would
determine that the embryo *was* human.

John Harshman

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Apr 29, 2013, 7:57:27 PM4/29/13
to
In that case, right after fertilization would be a good time. The
difference between a macrolecithal and a microlecithal egg is
pronounced. Even if the microlecithal egg distinctly remembers being
macrolecithal only a hundred million years ago.

Richard Norman

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Apr 29, 2013, 8:02:37 PM4/29/13
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On Mon, 29 Apr 2013 16:14:08 -0700 (PDT), Ron O <roki...@cox.net>
wrote:
Yes, the structure of the bird egg is so massively different from that
of a mammal that the difference is immediately obvious.


jillery

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Apr 29, 2013, 8:12:09 PM4/29/13
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I am no expert, but IIUC genetic analysis can tell them apart at the
single-cell stage. Or are you asking about features at the
macroscopic level?

John Harshman

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Apr 29, 2013, 8:16:29 PM4/29/13
to
But isn't an early mammal embryo also flat? If we ignore the
extra-embryonic membranes, is there a big difference between, e.g.,
avian and mammalian gastrulas?

Robert Carnegie

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Apr 29, 2013, 8:36:25 PM4/29/13
to
On Tuesday, 30 April 2013 01:02:37 UTC+1, Richard Norman wrote:
> Yes, the structure of the bird egg is so massively different from that
> of a mammal that the difference is immediately obvious.

Yeah, c'mon, it has a shell.

Paul J Gans

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Apr 29, 2013, 9:45:55 PM4/29/13
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OK. Now you are in for a bad spell of chick humor. After all
most of the chicks I know are the very image of human.

--
--- Paul J. Gans

Bob Berger

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Apr 29, 2013, 9:57:01 PM4/29/13
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In article <kln7oj$4jb$3...@reader1.panix.com>, Paul J Gans says...
I KNEW that was coming, and by whom. :-)

Richard Norman

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Apr 29, 2013, 10:19:59 PM4/29/13
to
The very first cleavage is different. Mammals have holoblastic
cleavage where the zygote divides completely splitting the tiny yolk
quantity between the two cells. Birds have meroblastic cleavage where
only the "animal pole" part of the cell actually divides; the yolk is
not separated. Of course monotremes have large yolks and meroblastic
cleavage but they don't really count. Wikipedia also lists other
characteristics unique to early placental mammalian embryos -- the
development of the trophoblast, for example, necessary for embedding
into the uterus and forming the placenta, and separated from the inner
cell mass which forms the embryo.

Yes there are blastulas, gastrulas, neurulas and all but they look
very different.

John Harshman

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Apr 29, 2013, 11:55:09 PM4/29/13
to
I would consider everything up to the development of the trophoblast to
be prior to formation of the embryo.

> Yes there are blastulas, gastrulas, neurulas and all but they look
> very different.

Do they? They look quite similar to me.

Arkalen

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Apr 30, 2013, 4:49:34 AM4/30/13
to
I thought maybe you meant two different human embryos from each other,
in which case the answer would be "even at 9 months it can be difficult".

(In the case of twins I've had trouble at 213 months)

Arkalen

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Apr 30, 2013, 4:52:26 AM4/30/13
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I read somewhere that development followed a kind of hourglass shape,
with initial stages varying a lot between groups but becoming very
similar at the pharyngula (?) stage, and then diverging again.

Something about that stage being the one where cells are just beginning
to differentiate ?

Richard Norman

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Apr 30, 2013, 8:09:37 AM4/30/13
to
That hourglass depends on whether you look for differences or look for
similarities. The earliest cleavage stages differ in different
animals: holoblastic vs. meroblastic, radial vs. bilateral,
determinate vs. indeterminate. Diagrams illustrating these emphasize
these differences.

Ignoring those differences, there is a general trend in bilateral
animals: morula, blastula, bastrula. Vertebrate animals have
additional shared stages: neurula, pharyngula. Diagrams illustrating
these emphasize the similarities.

As you get more complex morphogenesis and organogenesis more and more
differences between animals becomes evident. However you still have
similarities. The whole Haeckel drawings controversy is because those
drawings emphasized the similarities by underplaying the differences.
The differences are real but so are the similarities.

Look carelessly and you can easily see the difference between bird and
mammal right from the onset. Look closely and you cannot readily see
the differences between various placental mammals for a substantial
length of time.

Walter Bushell

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Apr 30, 2013, 8:55:44 AM4/30/13
to
In article <kln8d...@drn.newsguy.com>,
Hey, it easily could have be Mr. Bushell.

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

David Canzi

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Apr 30, 2013, 9:34:21 AM4/30/13
to
The question probably should have been "what's the difference
between a teal?"

--
David Canzi | Eternal truths come and go. |

eridanus

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Apr 30, 2013, 12:19:07 PM4/30/13
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El martes, 30 de abril de 2013 00:30:21 UTC+1, Burkhard escribi�:
Horny almighty Zeus fell in love with the beautiful princess Leda. But
fearing the god to frighten the beautiful lady with hist powerful body
and shining image, he disguised as might white male swan, for she loved
a lot the swans. Then, the divine male swan began to walk up and down, swaggering his rear to excite the passion of the princess. She began
to drool with the divine swaggering and opened up for the divine swan.
Fruits of the divine copulation Leda laid an egg, from which were
hatched Helen, Castor and Polydeuces; and in consequence Leda was
deified as the goddess Nemesis. It can be seen in the sky forming
the figure of a Swan, and people talk of these cluster as the stars
of the swan to celebrate the divine copulation of Zeus with Leda.
Other gospels tell quite different stories but all those had been
declared heretic and apocryphal gospels.

Eridanus

gave out

chris thompson

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Apr 30, 2013, 12:25:17 PM4/30/13
to
On Apr 30, 8:09�am, Richard Norman <r_s_nor...@comcast.net> wrote:
> On Tue, 30 Apr 2013 09:52:26 +0100, Arkalen <arka...@inbox.com> wrote:
> >On 30/04/13 04:55, John Harshman wrote:
> >> On 4/29/13 7:19 PM, Richard Norman wrote:
> >>> On Mon, 29 Apr 2013 17:16:29 -0700, John Harshman
> >>> <jharsh...@pacbell.net> �wrote:
>
> >>>> On 4/29/13 5:02 PM, Richard Norman wrote:
> >>>>> On Mon, 29 Apr 2013 16:14:08 -0700 (PDT), Ron O<rokim...@cox.net>
Thank you, Ron, Richard and John. Despite my initial idiotic typo,
this is exactly the kind of information I was hoping for.
Unfortunately, I tossed my Embryology textbook long ago, otherwise I
would have just looked up the answers- and I freely admit to being too
lazy to do a web search. Sometimes, it just seems like a lot more work
to scour the web than to open a paper book.

Thanks

Chris

Bob Casanova

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Apr 30, 2013, 1:20:07 PM4/30/13
to
On Mon, 29 Apr 2013 15:16:24 -0700, the following appeared
in talk.origins, posted by John Harshman
<jhar...@pacbell.net>:
Down, boy!
--

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

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Apr 30, 2013, 1:22:29 PM4/30/13
to
On Mon, 29 Apr 2013 17:36:25 -0700 (PDT), the following
appeared in talk.origins, posted by Robert Carnegie
<rja.ca...@excite.com>:
Ah, but which shell is the embryo under?

Bob Casanova

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Apr 30, 2013, 1:24:22 PM4/30/13
to
On Tue, 30 Apr 2013 08:55:44 -0400, the following appeared
in talk.origins, posted by Walter Bushell <pr...@panix.com>:

>In article <kln8d...@drn.newsguy.com>,
> Bob Berger <Bob_m...@newsguy.com> wrote:
>
>> In article <kln7oj$4jb$3...@reader1.panix.com>, Paul J Gans says...
>> >
>> >chris thompson <chris.li...@gmail.com> wrote:
>> >>On Monday, April 29, 2013 6:06:15 PM UTC-4, chris thompson wrote:
>> >>> Hi
>> >>>
>> >>>
>> >>>
>> >>>At what point can one reliably distinguish between a human embryo and a
>> >>>human
>> >>>embryo?
>> >>>
>> >>>
>> >>>
>> >>> Chris
>> >
>> >>ACK human embryo and chick embryo. My bad.
>> >
>> >OK. Now you are in for a bad spell of chick humor. After all
>> >most of the chicks I know are the very image of human.
>>
>> I KNEW that was coming, and by whom. :-)
>
>Hey, it easily could have be Mr. Bushell.

....or Wilkins, if he happened to be tuned in.

Desertphile

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Apr 30, 2013, 3:31:10 PM4/30/13
to
On Mon, 29 Apr 2013 15:06:15 -0700 (PDT), chris thompson
<chris.li...@gmail.com> wrote:

> Hi
>
> At what point can one reliably distinguish between a human embryo and a human embryo?

Never.

> Chris


--
Nemo me impune lacessit.
"A patriot must always be ready to defend his country against his government."

Walter Bushell

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Apr 30, 2013, 2:31:18 PM4/30/13
to
In article
<da0a88cc-454b-41a7...@t5g2000yql.googlegroups.com>,
chris thompson <chris.li...@gmail.com> wrote:

> Thank you, Ron, Richard and John. Despite my initial idiotic typo,
> this is exactly the kind of information I was hoping for.
> Unfortunately, I tossed my Embryology textbook long ago, otherwise I
> would have just looked up the answers- and I freely admit to being too
> lazy to do a web search. Sometimes, it just seems like a lot more work
> to scour the web than to open a paper book.
>
> Thanks
>
> Chris

I think that was a thinko rather than a typo. Or an intermediate case,
problem exists between cerebellum and keyboard.

Desertphile

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Apr 30, 2013, 3:31:30 PM4/30/13
to
On Mon, 29 Apr 2013 17:40:54 -0500, Free Lunch <lu...@nofreelunch.us>
wrote:

> On Mon, 29 Apr 2013 15:16:24 -0700, John Harshman
> <jhar...@pacbell.net> wrote in talk.origins:
>
> >On 4/29/13 3:06 PM, chris thompson wrote:
> >> Hi
> >>
> >> At what point can one reliably distinguish between a human embryo and a human embryo?
> >
> >What's the difference between a duck?
>
> Why a duck?

Because she's dressed like one!

Desertphile

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Apr 30, 2013, 3:31:46 PM4/30/13
to
On Tue, 30 Apr 2013 10:20:07 -0700, Bob Casanova <nos...@buzz.off>
wrote:

> On Mon, 29 Apr 2013 15:16:24 -0700, the following appeared
> in talk.origins, posted by John Harshman
> <jhar...@pacbell.net>:
>
> >On 4/29/13 3:06 PM, chris thompson wrote:
> >> Hi
> >>
> >> At what point can one reliably distinguish between a human embryo and a human embryo?
> >
> >What's the difference between a duck?
>
> Down, boy!

No, that's an elephant.

jillery

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Apr 30, 2013, 3:33:39 PM4/30/13
to
On Tue, 30 Apr 2013 12:31:10 -0700, Desertphile
<Deser...@spammegmail.com> wrote:

>On Mon, 29 Apr 2013 15:06:15 -0700 (PDT), chris thompson
><chris.li...@gmail.com> wrote:
>
>> Hi
>>
>> At what point can one reliably distinguish between a human embryo and a human embryo?
>
>Never.


It was a trick question, as in his mind was playing tricks on him. You
might have noticed I have that problem too!

SkyEyes

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Apr 30, 2013, 5:30:53 PM4/30/13
to
On Apr 30, 11:36�am, Desertphile <Desertph...@spammegmail.com> wrote:
> On Tue, 30 Apr 2013 10:20:07 -0700, Bob Casanova <nos...@buzz.off>
> wrote:
>
> > On Mon, 29 Apr 2013 15:16:24 -0700, the following appeared
> > in talk.origins, posted by John Harshman
> > <jharsh...@pacbell.net>:
>
> > >On 4/29/13 3:06 PM, chris thompson wrote:
> > >> Hi
>
> > >> At what point can one reliably distinguish between a human embryo and a human embryo?
>
> > >What's the difference between a duck?
>
> > Down, boy!
>
> No, that's an elephant.

You can't get down off an elephant. You only get down off a duck.

Brenda Nelson, A.A.#34
skyeyes nine at cox dot net OR
skyeyes nine at yahoo dot com

Earle Jones

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Apr 30, 2013, 7:13:20 PM4/30/13
to
In article <fnttn8dsed9hk8d6h...@4ax.com>,
Free Lunch <lu...@nofreelunch.us> wrote:

> On Mon, 29 Apr 2013 15:16:24 -0700, John Harshman
> <jhar...@pacbell.net> wrote in talk.origins:
>
> >On 4/29/13 3:06 PM, chris thompson wrote:
> >> Hi
> >>
> >> At what point can one reliably distinguish between a human embryo and a
> >> human embryo?
> >
> >What's the difference between a duck?

*
One of his feet are both the same.

earle
*

Bob Casanova

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May 1, 2013, 5:57:28 PM5/1/13
to
On Tue, 30 Apr 2013 14:30:53 -0700 (PDT), the following
appeared in talk.origins, posted by SkyEyes
<skye...@cox.net>:

>On Apr 30, 11:36�am, Desertphile <Desertph...@spammegmail.com> wrote:
>> On Tue, 30 Apr 2013 10:20:07 -0700, Bob Casanova <nos...@buzz.off>
>> wrote:
>>
>> > On Mon, 29 Apr 2013 15:16:24 -0700, the following appeared
>> > in talk.origins, posted by John Harshman
>> > <jharsh...@pacbell.net>:
>>
>> > >On 4/29/13 3:06 PM, chris thompson wrote:
>> > >> Hi
>>
>> > >> At what point can one reliably distinguish between a human embryo and a human embryo?
>>
>> > >What's the difference between a duck?
>>
>> > Down, boy!
>>
>> No, that's an elephant.
>
>You can't get down off an elephant. You only get down off a duck.

Now say the secret word and win $100.

Walter Bushell

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May 4, 2013, 11:09:36 AM5/4/13
to
In article <8t33o8t182n0irosc...@4ax.com>,
Bob Casanova <nos...@buzz.off> wrote:

> On Tue, 30 Apr 2013 14:30:53 -0700 (PDT), the following
> appeared in talk.origins, posted by SkyEyes
> <skye...@cox.net>:
>
> >On Apr 30, 11:36 am, Desertphile <Desertph...@spammegmail.com> wrote:
> >> On Tue, 30 Apr 2013 10:20:07 -0700, Bob Casanova <nos...@buzz.off>
> >> wrote:
> >>
> >> > On Mon, 29 Apr 2013 15:16:24 -0700, the following appeared
> >> > in talk.origins, posted by John Harshman
> >> > <jharsh...@pacbell.net>:
> >>
> >> > >On 4/29/13 3:06 PM, chris thompson wrote:
> >> > >> Hi
> >>
> >> > >> At what point can one reliably distinguish between a human embryo and
> >> > >> a human embryo?
> >>
> >> > >What's the difference between a duck?
> >>
> >> > Down, boy!
> >>
> >> No, that's an elephant.
> >
> >You can't get down off an elephant. You only get down off a duck.
>
> Now say the secret word and win $100.

Actually down from a goose is better.

Richard Norman

unread,
May 4, 2013, 11:25:49 AM5/4/13
to
On Sat, 04 May 2013 11:09:36 -0400, Walter Bushell <pr...@panix.com>
wrote:

>In article <8t33o8t182n0irosc...@4ax.com>,
> Bob Casanova <nos...@buzz.off> wrote:
>
>> On Tue, 30 Apr 2013 14:30:53 -0700 (PDT), the following
>> appeared in talk.origins, posted by SkyEyes
>> <skye...@cox.net>:
>>
>> >On Apr 30, 11:36 am, Desertphile <Desertph...@spammegmail.com> wrote:
>> >> On Tue, 30 Apr 2013 10:20:07 -0700, Bob Casanova <nos...@buzz.off>
>> >> wrote:
>> >>
>> >> > On Mon, 29 Apr 2013 15:16:24 -0700, the following appeared
>> >> > in talk.origins, posted by John Harshman
>> >> > <jharsh...@pacbell.net>:
>> >>
>> >> > >On 4/29/13 3:06 PM, chris thompson wrote:
>> >> > >> Hi
>> >>
>> >> > >> At what point can one reliably distinguish between a human embryo and
>> >> > >> a human embryo?
>> >>
>> >> > >What's the difference between a duck?
>> >>
>> >> > Down, boy!
>> >>
>> >> No, that's an elephant.
>> >
>> >You can't get down off an elephant. You only get down off a duck.
>>
>> Now say the secret word and win $100.
>
>Actually down from a goose is better.

Eider will do.

Bob Casanova

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May 4, 2013, 1:16:50 PM5/4/13
to
On Sat, 04 May 2013 11:09:36 -0400, the following appeared
in talk.origins, posted by Walter Bushell <pr...@panix.com>:

>In article <8t33o8t182n0irosc...@4ax.com>,
> Bob Casanova <nos...@buzz.off> wrote:
>
>> On Tue, 30 Apr 2013 14:30:53 -0700 (PDT), the following
>> appeared in talk.origins, posted by SkyEyes
>> <skye...@cox.net>:
>>
>> >On Apr 30, 11:36 am, Desertphile <Desertph...@spammegmail.com> wrote:
>> >> On Tue, 30 Apr 2013 10:20:07 -0700, Bob Casanova <nos...@buzz.off>
>> >> wrote:
>> >>
>> >> > On Mon, 29 Apr 2013 15:16:24 -0700, the following appeared
>> >> > in talk.origins, posted by John Harshman
>> >> > <jharsh...@pacbell.net>:
>> >>
>> >> > >On 4/29/13 3:06 PM, chris thompson wrote:
>> >> > >> Hi
>> >>
>> >> > >> At what point can one reliably distinguish between a human embryo and
>> >> > >> a human embryo?
>> >>
>> >> > >What's the difference between a duck?
>> >>
>> >> > Down, boy!
>> >>
>> >> No, that's an elephant.
>> >
>> >You can't get down off an elephant. You only get down off a duck.
>>
>> Now say the secret word and win $100.
>
>Actually down from a goose is better.

I'd like to take a gander at the data.
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