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Re: Paleo documentaries (was re: T. rex vision)

Tom Holtz wrote:

>The most extreme example of this was in the "dragons of the sea" episode.
>While discussing the reasons that a reptile might become secondarily
>aquatic (specifically, abundant food sources), they showed a picture of the
>Burgess Shale invertebrate Opabina reaching for one of the smaller Burgess
>Shale arthropods.  Now, granted, the head of an Elasmosaurus and the
>feeding organ of Opabina are somewhat similar, but this was a mistake 450
>million years off, about creatures many orders of magnitude difference in
>size, from completely different clades in Animalia (okay, the phylogenetic
>position of Opabina is far from certain, but it sure isn't a

_Opabinia_ is an arthropod or a lobopod according to a new classification.
It is no longer a "wierd wonder", but has an ancestry going back to the
Lower Cambrian. The suggestion of a vertebrate affinity is a slight which
cannot be left unanswered :-)

>The title was something like "Forgotten Worlds, Vanished Lives".  An
>appealling aspect of this series was the fact that a good deal of attention
>was paid to invertebrates.

And quite right too!


cnedin@geology.adelaide.edu.au,   nedin@ediacara.org
Many say it was a mistake to come down from the trees, some say
the move out of the oceans was a bad idea. Me, I say the stiffening
of the notochord in the Cambrian was where it all went wrong,
it was all downhill from there.