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Big aquatic vertebrates (WAS: Re: Pterosaur size)
On 12/13/06, David Marjanovic <email@example.com> wrote:
As clear as for terrestrial vertebrates, I'd say. You might like the fact that
the biggest ichthyosaur (and probably the biggest marine vertebrate before
*Basilosaurus*) was Triassic, though -- but then it is far from the ancestry of
the later ichthyosaurs.
This reminds me of something I've long found a bit odd - since the
Triassic or so, most of the really big aquatic vertebrates, both
predators and plankton-feeders, have been tetrapods. The whales win in
both categories (sperm whales and blue whales respectively), but even
discounting them the biggest non-tetrapods are beaten by various
marine reptiles, far as I know. (Leedsichthys and whale sharks are
smaller than that mega-ichthyosaur, and the biggest pliosaurs appears
to have out-sized Carcharodon megalodon, the biggest predatory fish I
Land might seem an odd route to maritime gigantism, but it's
apparently the best one. The only explanation I've seen suggested is
that air-breathing is more effective than gill-breathing, even tho the
gill-breathers can breathe continuously.
Why can't you be a non-conformist just like everybody else?