what does bigger brain mass mean?

Mike Lieber (U28550@UICVM.BITNET)
Sun, 5 Feb 1995 18:11:18 CST

I've been following the discussion of brain development with interest. I miss
what appears to me to be crucial data in this discussion. What, specifically,
does a lager brain mass in one population, as compared with other populations,
mean? If people in cold climate develop larger brain mass than those in
warmer climates, does this mean that they have more brain cells? If so, how
are these "surplus" cells distributed? Do they all go into the cerebral cortex
or are they distributed, say, evenly through the cerebellum, the medulla, the
cerebrum, etc.? Does anyone know? Has anyone asked? Is anyone looking?

If larger brain mass does not mean more brain cells, then where is that extra
mass located and what are its constituents? Given that more heat is lost
from the head than from elsewhere on the body, might that larger mass not have
something to do with heat conservation? If so, then I would suppose that
extra brain cells be maladaptive, given that the resources that added mass
requires would be taken up by processing rather than by insulation. More
brain cells in a cold climate would pose a problem of oxygenation as well as

Isn't the question of intelligence premature until these substantive questions
are answered?
Mike Lieber