Re: BADD BCF

["Nicholas R. Longrich" <longrich@citmail.Princeton.EDU>]

On Tue, 5 Dec 1995 Dinogeorge@aol.com wrote:
> The main problem I've always had with the BADD/ground-up scenario is getting
> a 20-50 kg theropod with relatively small forelimbs to evolve into a 2-5 kg
> dino-bird with grasping wings. It _could_ happen, but in my opinion it is
> _far_ less likely than having a 2-5 kg dino-bird with grasping wings to
> evolve into a 20-50 kg theropod.
        I'm skeptical. You say that theropods can't be bird ancestors 
because they're too big, but how do you know that? There could have been 
many small theropods. Yes, there is little evidence of this. There is 
little evidence of protobirds, either, however, so that is hardly a 
legitimate reason to prefer protobirds over small theropods as bird 
ancestors. Compsognathus, though not especially close to birds, shows 
that relatively small theropods existed. And I've seen footprints that 
would fit on a quarter, maybe a nickel, from theropods. They're mind 
blowing. I suppose there's no real way of knowing they were adults, in 
the same way there's no real way of knowing they weren't. 
        Personally, I think arboreality is an interesting and plausible 
way to explain why the first dinosaurs were bipedal. And I like the idea 
of Velociraptor and kin as flightless birds, but I question all 
the stuff in between which seems much more based on speculation (and some 
of you will say- as if the other ideas AREN'T?- so yeah, it is all very 
speculative).
        -nick L.