Ask A Scientist© Biology Archive

status       student
age          18

Question -   Do you think it is possible that our ancestors were
actually black, and that a gene mutation for an enzyme in
the metabollic pathway of melanin meant that not enough melanin was
produced some of us ended up with white skin. Primitive apes have black skin,
and we evolved from them, so doesn't this mean that humans orginally had
black skin???
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Most likely, yes, humans probably evolved from dark-skinned ancestors.

I will take issue, however, with your statement that "primitive apes have
black skin;"  we can't say that for absolute certain, because we have no
primitive apes to compare to.  All we have now are modern apes.  All modern
apes - homo sapiens, pan troglodytes, gorilla gorilla - are highly, probably
equally, evolved.  (One could make an argument that homo sapiens is in many
ways more generalized - note the generalized dentition, fragile skeleton,
etc. - than other modern apes, and thus could be said to be more primitive.)
As far as that goes, the only modern apes with white skin I know of are a
color variant of homo sapiens.

Richard E. Barrans Jr., Ph.D.
Assistant Director, PG Research Foundation
Darien, IL USA
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This is an interesting hypothesis but we'll probably never really know.  Some
have speculated that as humans moved north, the light intensity decreased.
Humans need Vitamin D to be able to absorb calcium for bone growth.  Vitamin
D can be manufactured in the lower layers of the skin.  Perhaps there was a
mutation and the people who had it were better adapted to the light levels in
the higher and lower latitudes.

Van Hoeck
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