Re: Continental predators, etc.

["David Marjanovic" <david.marjanovic@gmx.at>]

>     Another thought on "why oviparousness" in birds - the weight! [...]
> Eggs among birds are laid one at a time, usually each day
> of every other day, in sharp contrast to those of lepidosaurs, turtles and
> crocs which complete thier clutches all at once. (personal opinon mine:
> dinosaurs probably laid "all-at-once" clutches - at least _most_
dinosaurs.)

Very logical -- just untrue :-)
Crocs lay lots of small eggs at a time. Oviraptorids and *Troodon* at least
laid 2 relatively big eggs at a time, one per ovary. Living birds have lost
the right ovary and therefore lay only one even bigger egg at a time,
exceptions are AFAIK the kiwi and at least one atavistic chicken: those lay
2 eggs at once.
My thoughts on this are that if producing fewer eggs at once really is a
weight reduction necessary for flying then this must have been present
_before_ flight.

> The only flighted animal I know of which gives birth  to living young is
the
> bat, which is usually limited to one or at the most two young at a time,
and
> soon begins to leave the kids in the cave.

No need for the singular here. How many species are there? 800? 900? I
forgot...