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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].

Forgive me Stan.. Despite text-book dogma, lissamphibians* are the most diverse
of all parents perhaps among the tetrapods. Both frogs and salamanders go the
whole range from aquatic eggs, through terrestrial eggs, to vivapary. Relatively
few urodeles of which I am aware lay eggs as large gelatinous clumps - most
aquatic oviparous forms lay single eggs on plant leaves. _Triturus_ newts are
well known for depositing an egg on a leaf and then folding it over to form a
little envelope. 

Among the apparently most primitive of living urodeles are the Asian hynobiids
(famous for being very resistant to low temps, they have even survived
encapsulation in ice for several decades). Several of these lay eggs on the
inside of a damp tree trunk or other structure, the male then guards them till
they hatch as miniature adults. Similar strategies are employed by the
_Salamandra_ species, but in some situations (temp and altitude dependant) they
can go one better and develop young ovovivaparously. The Alpine salamander (_S.
atra_) does this as a rule, while the Fire salamander (_S. salamandra_) only
does it in part of its range. While as many as 30 embryos may be there
initially, only one or two are eventually born. How's that for sibling rivalry.

Obviously, not enough is known of Cret salamanders to ponder about their
reproductive strategies any further. That extant lissamphibians are among the
most vulnerable and fragile of ecosystem components, especially in the face of
man-made pollutants (and effects of volcanicity?), does suggest that something
very odd was going on late in the K, purely because these animals *didn't* have
a mass die-off. One of the first groups you'd expect to go extinct in a bolide
impact scenario would be the soft-bodied, hyper-absorbent frogs and salamanders.
A number of families are now known from the Mesozoic (discoglossids and hylids
being recently reported), and are still around (they haven't.... croaked it..).
Probably, therefore, our assumptions are in error.

*One or two s?

"We intercepted no transmissions. Aaah... This is a consular ship. We're on a
diplomatic mission"

DARREN NAISH