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RE: Yet more on pterosaur quad arm posture



Ok, well let's just hold ourselves to the best language we're capable of, 
rather than the worst we've seen on the DML.


________________________________________
From: owner-DINOSAUR@usc.edu [owner-DINOSAUR@usc.edu] on behalf of Tim Williams 
[tijawi@gmail.com]
Sent: Tuesday, July 16, 2013 12:05 AM
To: dinosaur@usc.edu
Subject: Re: Yet more on pterosaur quad arm posture

Jason Brougham <jaseb@amnh.org> wrote:


> What has sometimes rubbed me the wrong way in our discussions is your use of 
> absolute language, favoring
> words like "was" or "is", when different authoritative sources may actually 
> disagree on those points and when,
> regardless of any disagreement, those sources maintain the proper scientific 
> uncertainty in their language.


Well, it depends upon the context.  I frequently preface my statements
with terms such as "hypothesis" or "interpretation", to make it clear
that I'm putting forward ideas rather than bald facts.  Other times I
use qualifers such as "apparently" or "putative" or "likely".
However, other times I do make statements that I regard as based on
hard data, for example that _Microraptor_ was not specialized for
arboreality.  In that context, I'm trying to provide an antidote to
(what I regard as) some rather brazen claims regarding arboreality in
theropods.  (I have the image of GSP's tree-climbing _Ornitholestes_
in my head as I write this.)


> You say:
>
> Fowler et al. (2011) are of the same view: "As such, the first
> appearance of a fully reversed hallux is uncertain, and may not be
> strictly definable since translocation was probably gradual."
>
> Yet, you see, you said that it "was" gradual, when the authors that you cite 
> use properly qualified language:
> "uncertain", "may", "probably".


Yes, but Jason, that quote was taken from a peer-reviewed scientific
paper.  One would expect there to be sufficient qualifiers, since
supporting data on the evolution of hallucal orientation were outside
the scope of that study, which was principally concerned with the
grasping abilities of the


The DML is a different matter.  One of the agreeable aspects about the
DML is that it promotes a free and open exchange of scientific ideas.
For example, I enjoy reading GSP's ideas on arboreal theropods, even
though I am skeptical of most of those ideas.  (I might add that GSP
advances his ideas far more aggressively and assertively than most
people on this list do, including myself.)  Yet, if GSP submitted many
of his ideas to a scientific journal (such as _Microraptor_ being a
specialized arborealist), I'd bet that those ideas would meet quite a
few obstacles in terms of publication.


> I would not be such a stickler on tone, except that you have accused others 
> of being unscientific in the past.


Lets' be careful here.  One should make a distinction about
criticizing ideas versus criticizing people themselves.  I have
certainly criticized approaches that rely too much on entirely
intuitive readings of the evidence rather than rigorous testing of
hypotheses.  From that perspective, I have been a stickler for
methodology. However, I try to steer clear of criticizing individuals.
 I'll make exceptions when there are certain individuals who are
debasing the scientific process (such as D. Peters or some other
wingnuts who have popped up on the DML over the years.)  But they are
the exceptions, not the rule.


Over the past two centuries approaches toward reconstructing the
origin of avian flight has too often been bogged down in "just-so"
stories and chest-beating about who better "understands" the ecology
of early birds and their ancestors.  (The latter still goes on,
especially among the BANDits; but it is thankfully in decline.)  I'd
prefer to see hypotheses tested against the available data, using
methods such as phylogenetics, biomechanics, comparative morphology,
etc.  So when someone says "_Microraptor_ could perch" my response is:
"Show me HOW _Microraptor_ perched."


>I  would hate for a  student doing internet research in paleontology to see 
>your opinions on the DML and to think
> that the final word
rphology from Epidendrosaurus.


I'd hate to see that too.  But I'd hope that such a student would
consult the primary literature, and form their own views.  The DML is
a forum for the discussion of scientific ideas.  It is not a
short-cut.


> For example, the gradual evolution of the reversed hallux could be a relative 
> term, and open to debate as well.


Yes; I had thought my short blurb had made that clear.  Guess not.


>  It could just as likely have arisen in a hypothetical "end Jurassic 
> radiation", that took just a few million years
> to give rise to the confuciusornithids, sapeornithids, jeholornithids, and 
> diverse enantiornithines and
> ornithuromorphs that we see in the Early Cretaceous.


This is essentially compatible with my previous 'take' on the
evolution of the reversed hallux.  You've added a temporal context;
but as far as I can see there is no disagreement on the overarching
morphological process.  My major reservation with your hypothesis is
that I'm intrigued why Early Cretaceous theropods that are supposedly
highly arboreal are still stuck with the incipient or nascent arboreal
"adaptations" of their Jurassic forbears.


> So I humbly beg your consideration in adopting more open - minded language. I 
> will patrol my own as well.


Yes.  The mind is like a parachute: It works best when open.  (My
thanks to the desk calendar which offered me that trite little pearl
of wisdom.)






Cheers

Tim