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Re: Extinction once again (crocs)



> > > 4. Lots of terrestrial egg-laying vertebrates survived (turtles,
crocs,
> > > lizards/snakes, tuataras, monotremes...)...
>
> > They are mostly very small and can hide their nests in a greater variety
> > of places.  Crocs are totally dependent on wetlands, though.
>
> Although wetlands are today the most important nesting habitat for many
croc
> species, it is not true that they are totally dependent upon them. Crocs
> require access to freshwater during nesting, which may come from a variety
> of sources including tidal rivers and their upstream areas, isolated lakes
> and pools, or even flooded patches during wet season rains. Some species,
> such as Australian freshwater crocodiles or Nile crocodiles, utilise sand
> banks to lay their eggs and only require that the substrate be moist close
> to water. This can provide excellent inland nesting habitat.
>
> I would be interested in reviewing the ideas about the Eusuchia surviving
> the K-T extinction, if anyone has any.

AFAIK, current wisdom about their survival centers on the mild conditions in
fresh water. What is interesting, however, is that not only eusuchians
survived, but also dyrosaurid sea crocs (but they died off in the
catastrophe at the end of the Eocene!) and South American ziphodont crocs
(Baurusuchidae, Sebecidae, whatever) that are thought to have been
terrestrial carnivores (interesting that they evolved when there were
theropods all over the place).