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Tim Williams | 1 Feb 2010 01:04
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Re: Haplocheirus and Gregory S. Paul


Mark Pauline <markpauline <at> rocketmail.com> wrote:

> I'm sorry, that was imprecise of me.
> I must not have meant BCF but, rather, Mr. Paul's hypothesis
> that at least the most derived maniraptorans descended from
> an ancestor with flight capabilities superior to those in
> Archaeopteryx. 

No worries.  GSP's hypothesis has moved into the mainstream, at least as far as the concept of secondarily
flightless ("neoflightless") deinonychosaurs is concerned.  By contrast, BCF (proposed by G.
Olshevsky) has all but disappeared.  

However, the notion of "neoflightless" deinonychosaurs is not the most parsimonious explanation for the
character distribution seen across Maniraptora.

> What would we call this, the Secondarily
> Flightless Maniraptoran hypothesis?

Neoflightless hypothesis,  or just "2F" is the usual parlance.

> As for Oviraptorosaurs and Therizinosaurs, the most
> primitive known members of both groups have fewer, rather
> than more, features in common with birds than their derived
> members, suggesting that their ancestors were not
> aerodynamic. 

I think you raise an important point here.  However, I think it is a mistake to equate "bird-like" with
"aerodynamic".  The features that certain non-avian maniraptorans have in common with derived birds are
not always directly associated with flight in birds or if they are, they may not have evolved for that purpose.
(Continue reading)

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David Marjanovic | 1 Feb 2010 01:07
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Re: Did Feathers Evolve for Dispaly? We Still Don't Know!

>  I've heard that zoos need to mix certain natural dyes into their
>  flamingo food, otherwise the birds turn white.

Yes, and those are carotenoids (such as beta-carotene, which is the dye 
of carrots, and vitamin A, the same molecule split in half).
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Ronald Orenstein | 1 Feb 2010 01:16
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Re: Did Feathers Evolve for Dispaly? We Still Don't Know!

As I understand it no animal can directly synthesize carotenoids but must get them from their diet.  There is
a great deal of ornithological literature on this subject, especially from the lab of Geoffrey Hill,
particularly based on the hypothesis that carotenoid levels are an "honest signal" of fitness because
their presence is an indicator of overall health and ability to find sufficient amounts of food.
 Ronald Orenstein
1825 Shady Creek Court
Mississauga, ON L5L 3W2
Canada

________________________________
From: David Marjanovic <david.marjanovic <at> gmx.at>
To: DML <dinosaur <at> usc.edu>
Sent: Sun, January 31, 2010 7:07:25 PM
Subject: Re: Did Feathers Evolve for Dispaly? We Still Don't Know!

>  I've heard that zoos need to mix certain natural dyes into their
>  flamingo food, otherwise the birds turn white.

Yes, and those are carotenoids (such as beta-carotene, which is the dye of carrots, and vitamin A, the same
molecule split in half).
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Tim Williams | 1 Feb 2010 01:25
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Re: Haplocheirus does not confirm alvarezsaurs are maniraptoran

David Marjanovic <david.marjanovic <at> gmx.at> wrote:

> Ant-eaters don't need reach. (They can just walk closer.)
> They only need power.

I'm coming round to thinking that you're probably right here.  The giant ant-eater uses its fore-claws to
make a small breach in the ant or termite nest, then feeds on the insects that stream out.  However, the
ant-eater doesn't feed at any nest for too long: the ant-eater soon backs off to avoid the soldier caste. 
The ant-eater rarely destroys a nest, but survives by ingesting a relatively small number of insects from
a large number of nests.

So alvarezsaurs could have fed the same way.  Breach the nest (or insect-infested wood), slurp up some
emerging insects, then run away before the angry colony launch a full-scale attack.  Or maybe it breached
trees to access the sugar-rich sap - a much better food source than ants or termites.  And sap doesn't bite. 

 
> The trick is that all extant ones are (to varying degrees,
> but still) quadrupedal. To be useful in locomotion,
> forelimbs need a minimum length. Compromises result that the
> bipedal alvarezsaurids simply didn't need.

Nevertheless, a short reach would limit the alvarezsaur to breaching nests or trees that were shoulder
height (or lower), rather than head height.  I still think you're right though.

Cheers

Tim
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Dann Pigdon | 1 Feb 2010 01:32
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RE: Bistahieversor sealeyi, NM tyrannosaurid

On Sun, Jan 31st, 2010 at 3:23 AM, Jaime Headden <qi_leong <at> hotmail.com> wrote:

>   I would also like to share the feeling of disphoria Mike Taylor
> felt when I first heard someone else pronounce "calcaneum" at SVP
> 1999. Not at all what I expected.

Is there a concensus on how it's pronounced? I'm torn between 'Kal-Kaneum' and 'Kalsa-Neum' (as 
in 'calcium'). Excuse the pseudophonetics.

I've never been sure exactly which syllable to emphasise in 'astragalus' either. Is it 'Astra-Galus' 
or 'Astrag-Alus'?

Should I just avoid mentioning the lower hind limbs entirely? :-)

--

-- 
_____________________________________________________________

Dann Pigdon
GIS Specialist                         Australian Dinosaurs
Melbourne, Australia               http://home.alphalink.com.au/~dannj
_____________________________________________________________
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Mark Pauline | 1 Feb 2010 01:44
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Re: Haplocheirus and Gregory S. Paul


However, the notion of "neoflightless" deinonychosaurs is not the most parsimonious explanation for the
character distribution seen across Maniraptora.

Wouldn't you agree that, since a 4-winged configuration is now seen in the basalmost and/or oldest members
of the dromaeosaurs (Microraptor) and troodontids (Anchiornis), and since their sister group is the
Avialae, that it is far more likely that they all three inherited aerodynamic behaviors from the
ancestral paravian than that they each acquired them independently? I know that we must hold out the
possibility that Microraptor and Anchiornis didn't glide, but the body masses are so small, the arms are
so long, the sterna are so big and ossified, and the feathers are so long and form such large wings  that it
really seems more likely than not that they glided.

If you do agree, then aren't the larger, more derived deinonychosaurs secondarily glideless?

If so, aren't "neoglideless" deinonychosaurs the most parsimonious explanation?
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Tim Williams | 1 Feb 2010 01:45
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Re: Did Feathers Evolve for Dispaly? We Still Don't Know! (joke)


Dann Pigdon <dannj <at> alphalink.com.au> wrote:

> There was a study many years ago that showed that
> dung-eating amongst certain vulture species 
> in Africa supplies them with the carotenoids they require
> to keep the skin around their faces bright yellow.

I've heard Joan Rivers does the same thing.
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T. Michael Keesey | 1 Feb 2010 01:50
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Re: Bistahieversor sealeyi, NM tyrannosaurid

On Sun, Jan 31, 2010 at 4:32 PM, Dann Pigdon <dannj <at> alphalink.com.au> wrote:
> On Sun, Jan 31st, 2010 at 3:23 AM, Jaime Headden <qi_leong <at> hotmail.com> wrote:
>
>>   I would also like to share the feeling of disphoria Mike Taylor
>> felt when I first heard someone else pronounce "calcaneum" at SVP
>> 1999. Not at all what I expected.
>
> Is there a concensus on how it's pronounced? I'm torn between 'Kal-Kaneum' and 'Kalsa-Neum' (as
> in 'calcium'). Excuse the pseudophonetics.

"Kalkaneum" is more consistent with English patterns. "C" is realized
as "s" before front vowels ("i", "e"), but as "k" before central or
back vowels ("a", "o", "u"). Notice how "calcium" ("kalsium") confirms
this pattern. (And note that sometimes the "c" + front vowel
combination gets slurred into a "sh": "ocean", "atrocious".)

This is why some pronounce "diplodocid" as "diplodosid", despite
pronouncing "Diplodocus" as "Diplodokus". It can get hard to keep
straight, though, and I have heard "diplodosoid" for "diplodocoid",
which kind of sets my teeth on edge, in spite of my descriptivist
leanings.
--

-- 
T. Michael Keesey
Technical Consultant and Developer, Internet Technologies
Glendale, California
http://tmkeesey.net/
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Nick Pharris | 1 Feb 2010 02:15
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RE: Bistahieversor sealeyi, NM tyrannosaurid

Quoting Dann Pigdon <dannj <at> alphalink.com.au>:

> On Sun, Jan 31st, 2010 at 3:23 AM, Jaime Headden  
> <qi_leong <at> hotmail.com> wrote:
>
>>   I would also like to share the feeling of disphoria Mike Taylor
>> felt when I first heard someone else pronounce "calcaneum" at SVP
>> 1999. Not at all what I expected.
>
> Is there a concensus on how it's pronounced? I'm torn between  
> 'Kal-Kaneum' and 'Kalsa-Neum' (as in 'calcium'). Excuse the  
> pseudophonetics.

Do you ever pronounce <c> as [s] when it appears in the sequence <ca>?  
  I'm pretty sure I don't...

> I've never been sure exactly which syllable to emphasise in  
> 'astragalus' either. Is it 'Astra-Galus'
> or 'Astrag-Alus'?

The stressed syllable would be the third-to-last (as-TRA-ga-lus) in  
both Latin and Greek.

--

-- 
****************************************************************
Nicholas J. Pharris
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Nick Pharris | 1 Feb 2010 02:25
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Re: Bistahieversor sealeyi, NM tyrannosaurid

Quoting "T. Michael Keesey" <keesey <at> gmail.com>:

> (And note that sometimes the "c" + front vowel
> combination gets slurred into a "sh": "ocean", "atrocious".)

This is a general fact about /s/ + /j/ sequences (/j/ representing the  
sound of the <y> in "yes"), seen also in words like "tissue" and even  
across word boundaries in phrases like "miss you" (which sometimes  
comes out rhyming with "tissue").

Similar processes apply to /z/ + /j/ (so that the sound in the middle  
of "Asia" is the sound at the beginning of "genre"), /d/ + /j/ (so  
that the first syllable of "education" sounds like the word "edge")  
and /t/ + /j/ (so that "got you" becomes "gotcha").  At least in my  
dialect.

--

-- 
****************************************************************
Nicholas J. Pharris
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