Re: Dinosaur Revolution Review (Baby Fuzz)

[Tim Williams <tijawi@gmail.com>]

Sim Koning <simkoning@msn.com> wrote:

>  Also, I think we should be careful when making arguments from analogy based 
> on extant birds.


Yes, I completely agree.  Modern Aves represent an oddball lineage of
theropods that just happened to dribble over the K-Pg boundary.
Although there is no such thing as a "typical" theropod, if there was
one then birds would be the group furthest from it.


> Imagine if we were unaware of the Hoatzin. I suspect many would likely 
> express incredulity at the notion that a species of bird could replace clawed 
> hands with wings as it matured.


Although certainly not commonplace, the presence in juveniles (and
subsequent loss) of wing-claws isn't that unusual among birds.
Turacos and mouse-birds also have them as juveniles.  The hoatzin
happens to be best-known example of this trait because the wing-claws
in this species persist for a very long time.


> http://geology.cwru.edu/~huwig/catalog/slides/695.I.12.jpg


Wow, I've never seen that before!





Cheers

Tim