Carol:
What we need to clarify here, in my opinion, is the reason why we
should care whether something is vertebrate or not.  Why would food
choices of our ancestors be divided along the vertebrate/invertebrate
line?  Seems to me it would be divided along the lines of whether a
particular animal food was available or not.

Jo:
I wondered about this as well, the distinction between vertebrate or
invertebrate food sources. I'd have to speculate that availability
was, if not the sole factor, the primary influence in determining
what prehistoric man consumed to meet their nutritional needs. i.e.
coastal communities ate various marine animals while landlocked
groups, game, fowl, eggs, insects, etc.

Have not contemporary native (relatively pristine) groups been
observed to include animal source foods despite living in tropical
environments abundant with fruit and vegetable sources? If I remember
correctly, mammals (monkeys, boars) were commonly hunted. And
freshwater fish consumed when available?

I suspect, and correct me if I'm in left field Stephanie / Arjen,
that the spine issue has more to do with a vegan inclination to
towards ethical distinctions, that for me to eat fresh squid (a
gastropod) or grasshopper (an insect) is somehow less abhorrent than
eating the heart and brain of Bambi. i.e. consuming "lower" animal
species is OK but ethics enters the picture when food sources exhibit
structures resembling human anatomy.

If biochemical adaptions are necessary for humans to consume
vertebrate flesh, I'd like to hear more about this.

Thanks,
Jo
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