Re: mosasaur babies/no marine dinos

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

> How would you compare metriorhynchids to mosasaurs
> with regards fishy body style?

Didn't they look like ichthyosaurs, complete with tail fin?
BTW, the LK (or earlier?) to Eocene marine crocs are the dyrosaurids, not
the dryosaurids :-) -- anyway, they looked relatively normal and apparently
didn't have fins.
Aquatic amniotes in freshwater? Dolphins, manatees, hesperornithiforms,
plesiosaurs, maybe mesosaurs also count; can't think of more. All others are
semiaquatic. Who knows, maybe there were freshwater metriorhynchids or
ichthyosaurs...

Maybe it's impossible to evolve viviparity when a calcified egg shell has
evolved. Don't know why, but it hasn't happened so far... unless the
suggestion that hesperornithiforms were viviparous is correct :-)
Is there a viviparous gecko?

Why are there no penguins in the northern hemisphere and never have been?
Today they only live in cold currents that produce blooming ecosystems, and
they evolved in the south, so I'd say they have never got farther north than
Galápagos and are unable to cross the equator. Likewise, the plotopterids
(convergent pelicans of the northern Pacific in the Miocene IIRC) etc.
haven't crossed it either.