[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
Re: THE WONDERFUL WORLD OF SALAMANDERS
> > And NO salamanders died, and I would call them non-stealthy egg-layers,
> > although they *are* aquatic egg-layers. [Salamander egg masses take
> > the form of large gelatinous clumps].
Do we really have that much good evidence on salamanders and
frogs? Can we even identify them past the generic level, or even past the
subfamily level? I've heard something to the effect that there are no
complete frogs known from the late K of NA.
The point being, could it be that the evidence is scanty enough on
amphibs to allow two completely contradictory scenarios that might fit
scenario #1: Not a single species of frog, toad, newt,
salamander, caecilian etc. went extinct at the K/T boundary. They all
made it through. There was not any decline in the number of individuals
in a species, either. If, however, an amphibian happened not to reappear on
the other side, it could merely be a problem of preservation, or else the
animal went extinct before or after the K/T for reasons utterly unrelated
to what did in the dinosaurs.
scenario #2: Frogs, toads, newts, salamanders, etc. got a good
thrashing at the K/T for the same reason(s) as dinosaurs. Most
species went extinct- in fact, only a relatively few individuals from
ONE species of each genera/subfamily (as the case may be) managed to
survive. In the depopulated post K/T world, however, their large
reproductive potential allowed the individuals to repopulate or even
create new species in the vacuum left. Very soon after the K/T, frogs
and salamanders were thriving and healthy.
These are just for the sake of argument, of course.
My question is: is the evidence of fossil amphibians good enough
to distinguish between these two extreme scenarios?