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Re: Status of _Caudipteryx_




Jaime,
I think it is perfectly acceptable to look at any animal with "flying" close relatives (colugos being one) and ask the question whether it is primitively (primarily) or secondarily flightless (in terms of "powered" flight). Thank goodness we have people like Dinogeorge who are seriously considering this in the case of theropods (or at least a subset of that group).
Whales have no close relatives that fly, so there is no need to ask this question. If Eric has said whales are primarily flightless, that might have been deserving of critical commentary. In the case of colugos, I see no problem in calling them primarily flightless. The probability that they are secondarily flightless is pretty low, but it is many orders of magnitude greater than the truly tiny probability for whales (and therefore labelling whale flightlessness would indeed be silly).
Therefore I would recommend that Eric not take your criticism on this point too seriously (I think it indicates scientific thinking on his part, and this should be encouraged, not discouraged). But I must admit that he could sometimes put the services of a spell-checker to good use [that is some friendly constructive criticism that I think would really serve him in the long run]. :-)
------Ken
P.S. Just read some newer posts, and think Eric is making a perfectly valid point in comparing colugos and Caudipteryx. Caudipteryx could very easily be closely related to an evolutionary transitional form in the development of avian flight. Likewise, colugos could be related to evolutionary transitional forms between a tree-shrew-like form and bats. Of course, the analogy will not hold up if Caudipteryx proves to be secondarily flightless and its symmetrically-vaned feathers evolved from flightworthy asymmetric feathers (which would no doubt have Dinogeorge grinning from ear to ear).
And Eric, the spell-checker wouldn't help with Hyracotherium, but would help with words like linear and equivalent. Typos are to be expected, but a pattern of spelling "guesswork" will detract from even the best-reasoned arguments. That said, if there are any misspellings in this message, I will be truly embarrassed. :-)
********************************************************
From: "Jaime A. Headden" <qilongia@yahoo.com>
Reply-To: qilongia@yahoo.com
To: dinosaur@usc.edu
Subject: Re: Status of _Caudipteryx_
Date: Fri, 29 Dec 2000 22:39:11 -0800 (PST)

Ken Kinman wrote:

<Just how closely flying lemurs are related to any particular groups of
bats is controversial (although both groups are regarded as belonging
to a single clade Archonta (along with primates and tree shrews, as
well as plesiadapiforms if one wishes to separate them from primates).>

<However, I would say that the vast majority of groups of organisms are
primitively or primarily flightless, and I'm sure even Dinogeorge would
agree that this applies to ornithischian and sauropodomorph dinosaurs.
I don't understand how you can say that there is no such thing as a
primitively flightless organism or primitively flightless dinosaurs.>

  I'm sorry, but in an evolutionary scenario, you can know an end
product, only in the present sense. We could be primitively aquatic,
but you wouldn't say this unless you _knew_ of a product that became
aquatic that stemmed from _us_. You going to tell me that whales are
primitively flightless? At some point, any organism _can_ be
flightless, but I've already expounded on _a posteriori_ statements.

  As a statement of evolution, one cannot say something is primtiive
without an evolutionary sequence that demonstrates transformation or
acquisition. Also, it would not be recommendable to assume a state that
an animal is not at, such as colugos (flying lemurs) being somehow
primitively flightless because for some reason a related group of
mammals became flighted. Huh? What does this say about the colugos? It
means nothing about flight except that it does not fly, like a relative
does. Supposedly bats and colugos are each others closest relatives, or
megachiropterans and colugosa (Volantia). It is not "primitively
flightless," it is flightless, full-stop.

> Eric's
> statements perhaps deserve to be challenged, but this seems to be a
> very odd
> way of doing it.  Therefore, I am more inclined to challenge your
> statements
> than his.
>                        ------Ken Kinman
> ********************************************************
> >From: "Jaime A. Headden" <qilongia@yahoo.com>
> >Reply-To: qilongia@yahoo.com
> >To: dinosaur@usc.edu
> >Subject: Re: Status of _Caudipteryx_
> >Date: Fri, 29 Dec 2000 20:28:55 -0800 (PST)
> >
> >Eric Lurio (at ELurio@aol.com) wrote:
> >
> ><Not neccessarily. The so-called "flying lemurs" are primitively
> >flightless, and I've read that they may be closely related to fruit
> >bats.>
> >
> >   There is no such thing as a primitively or "primarily" flightless
> >organism, because no animal trends towards a state with the intent
> to
> >reach it, such as the ability to fly. Appling a possible conclusion
> >doesn't mean the a posteriori conclusion applies to an organism.
> Okay
> >... dinosaurs are not primarily flightless, and no dinosaur will be,
> >even birds.
> >
> >   End rant,
> >
> >=====
> >Jaime A. Headden
> >
> >   Aaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhr-gen-ti-na
> >   Where the Wind Comes Sweeping Down the Pampas!!!!
> >
> >__________________________________________________
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=====
Jaime A. Headden

  Aaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhr-gen-ti-na
  Where the Wind Comes Sweeping Down the Pampas!!!!

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