Subject: Dolphins, brains, and evolution

Bob Cooper (
Mon, 1 Mar 1999 00:12:11 -0500

>Dear sir, I recently came across a news report that said dolphins had a
>much evolved brain than humans, millions of years ago (I think it was 30
>million years ago). Could you please explain why the dolphins could
>never use that intelligence and evolve further. Thank you. Amitabh
>Awasthi (southern India).

Hi Amitabh,
	I am not sure exactly what you asking so if this doesn't  answer
your question  please write back.
	Intelligence is a product of evolution.  Dobzhansky, et al. (1977)
suggests that intelligence may change the rate that a species evolves. For
instance the fact that human kind can manipulate his/her environment
limits, somewhat, the effects of natural selection. If we find ourselves
out in the cold: we use our brains and insulate ourselves from the cold by
putting on a jacket or starting a fire to keep us warm. If we were unable
to adapt to the cold or use our brain to get warm we would die; thereby
removing our genes from the gene pool (natural selection at work).
Dolphins, though they are not able to kindle a fire, have the ability, and
the intelligence, to move to warmer water or consume more food to generate
more heat if they get cold. But they cannot consciuosly evolve legs, gills
or even toes. That could take millions of years and only if the right
genetic and environmental conditions exist.

Evolution. T. Dobzhansky, F.J Ayala, G.L. Stebbins, J.W. Valentine. W.H.
Freeman and Co. 1977.

You might check out:
Evolution Process and Product. by E.O Dodson and P. Dodson
The Natural History of Whales and Dolphins, P.G.H. Evans.

I hope it helps,
Thanks for writing,
Bob Cooper