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Re: Thou Shalt Not Climb!
--- firstname.lastname@example.org wrote:
> It still looks as if we are using the derived state
> as evidence... very
> akin to saying, "Whales never used their back legs
> in aqueous
> locomotion, since as we all know, whales today use
> So, what I'm wondering, is how did selection take
> place for
> pre-perching birds that were landing in trees with
> zero adaptations for
How about those long, counterbalancing tails in
Archaeopterygiformes? Having that counterweight might
have allowed for grasping toes to be more than enough
to allow them to stay on a branch without the need for
The opposable hallux might have evolved in tandem with
the shrinking tail. Offhand I don't think that's what
the evidence shows. Regardless, this part would be
easy enough to test. Admittedly it would be nice if
we had a better record of tail loss in birds.
Currently, things seem rather polar. We have long
tailed _Archaeopteryx_ and _Rahonavis_ on one end, and
the tail-less rest of Aves on the other.
Anyway, there's one thought.
"I am impressed by the fact that we know less about many modern [reptile] types
than we do of many fossil groups." - Alfred S. Romer
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