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Dwight Stewert wrote:
<<....with reptiles and amphibians ranked only above insects, IF that. The
facts simply don't bare that out; it's a kind of prejudice (IMHO!). Reptiles
are better suited for certain niches. The shear endurance of reptiles
throughout vertebrate history amply proves that.>>
Indeed our mammal-ocentric views bely the fact that the 2nd or 3rd class
animals in fact out number mammals in diversity and biomass increadibly.
<<Correct me if I'm wrong (really asking for it here!), but aren't both birds
and mammals evolved from reptiles?>>
Well... it all depends on what you think is a reptile.... If you mean, as
according to the old-fashioned definition, diagnosed as any tetrapod that
doesn't have fir or feathers, yet does lay eggs on land, then yes, both
mammals and birds evolved from reptiles.
In point of fact however, according to rigourous phylogenetic definitions,
Reptilia is now defined to exclude mammals and their ancestors, and to INclude
birds and their ancestors (dinosaurs).