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Re: Velociraptor profiles and a little background
<My own feeling, for what it's worth: some active, warm-blooded
who were flexible in hunting strategies developed feather precursors
as a mutation and it persisted because it kept them warm. All
other behaviors were affected by having feathers; they adapted
to feathers and feathers to the adaptations.
Call it feathers came first.>
And you responded:
<Exactly as I wrote: you start out with a fully feathered, fully
Well, I didn't say anything about winged. Wings reduced arm/hand
capabilities so much that I have to think some progress toward
moving through the air was made before full wings would add more
than they lost.
A number of birds, not all, that concentrate on swimming lose
much of their wings, so swimming's not the first thing I think
of as encouraging wing development.
When I observed that 'feathered' animals could, and maybe did,
try a lot of different strategies, you commented:
<"Possible [they tried different strategies]" or "yes"? If "yes",
you are arguing for a pretty extreme generalist... might be improbable.>
Thinking of isolated populations. A group of animals in one
location may find a particular strategy most effective, another
group a different one. The different selective pressures would
eventually produce different species. (And very similar new
species would be generated if the same strategy were used in
widely separated locations.) Hence, the different strategies
being tried would lead to different speculations if someone were
expecting only a single answer. I'm suggesting multiple correct
answers for the lifestyle of feathered, pre-bird animals. Only
one or a few of these groups ever flew.
I'd settle for a conclusion of 'Not unreasonable.'
= = = Original message = = =
> <You get something like a dipper, sort of; *Archaeopteryx*
is IMHO an
> example of such an animal. (Difference: Dippers can already
> One adjustment: I think the people who say Archie was capable
> flight have a reasonable argument.
I was explicitely unexplicit about whether only "such animals"
too, can't fly in air. :-) Seriously, though... I can't tell
Archie's musculature was just enough or just not enough to fly
with, but its
wing feathers (except the isolated feather... which may therefore
from Archie) are more symmetric than those of all investigated
"Already" was meant to mean (it was late at night) that
lifestyle of dippers is secondary, their ancestors were able
to fly before
they extended flight into thw water.
> My own feeling, for what it's worth: some active, warm-blooded
> were flexible in hunting strategies
> developed feather precursors as a mutation and it persisted
> them warm. All other behaviors were affected by having feathers;
> adapted to feathers and feathers to the adaptations.
> Call it feathers came first.
Exactly as I wrote: you start out with a fully feathered, fully
coelurosaur. Such like... (should be at
http://dinosauricon.com/genera/bambiraptor.html, but I can't
site). (Wings -- long wing feathers, +- laterally oriented glenoids,
probably the semilunate -- evolved for brooding.)
> Because of selection, a range of behaviors is being looked
at like a
> Trees down? Yes. (Though, contra Tim, I still think an ambush
leap has a
> better angle from a large rock than from a tree.)
So it lived in mountaineous areas -- neat for the fossil record
> Ground up? Yes.
> Swimming? Yes.
> Name it? Yes.
"Possible" or "yes"? If "yes", you are arguing for a pretty extreme
generalist... might be improbable.
Aw. We should have had these amounts of snow in winter and not
mid-spring. The weather is getting crazier and crazier.
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