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Re: Nocturnal crocs?
> Dinosaur diversity was probably not affected much at the K/T
> (inasmuch as bird diversity making it through may well have
> been greater than non-avian esxtinction).
Dinosaur diversity was reduced to a few species of Neornithes... I don't
understand something here.
> Instead, the K/T represents the
> death of a niche--that filled by large oviparous species in terrestrial
> locations. This niche has been practically empty ever since!
Why should there be extra niches for _oviparous_ animals? How does this
affect their ecology?
> mammals and birds (and, to a lesser extent, reps) appear to be the agents
> keeping that niche empty. The question then becomes: at what time did
> this first start being the case?
IMHO modern mammals occupy quite closely the same niches as dinosaurs
earlier (some niches for large animals being empty since we emptied them in
> Mammals of the K/T in the western interior had reached the size where they
> _could_ have preyed on nests and hatchlings (judging by comparisons of
> today's pred and prey ratios, e.g., a hairy armadillo preying on rhea eggs
> is broadly comparable to a Didephodon preying on a dino egg).
Well, *Gobiconodon* also had such a size, and *Repenomamus* (*-nus*?) was
Such animals (along with LK varanoids) would have produced a selection
pressure for better nest defense/concealment, and obviously dinosaurs
> > > Small jackals today
> > > cannot approach ostrich nests in the day time but have no trouble at
> > > night.
> > Really? I thought the male sits on the nest at night?
> Whichever sex it is, it is driven off the nest by jackals taking advantage
> of their superior night vision.
Jackals have better night vision than ostriches? How come?