(hope I've got all the attributions right)
>
> > Tasha Howe wrote:
> >
> > <A student in intro psych. asked the question and I had no
> > <idea why most blondes' hair turns brown, do you?
> On Wed, 17 Nov 1999, Charles M. Huffman wrote:
> > I am skeptical about the claim. Possibly, your student is refering to
> > limited observations and you now have the opportunity to teach the student
> > about the danger or restrictions of such thinking. In other words, you may
> > not receive an answer to your question because there is none.
On Wed, 17 Nov 1999, Jeff Bartel wrote:
> >
> For whatever anecdotal evidence is worth, my wife and I were both blondes
> as young children (through age 7 or 8), and we both sport brown hair now.
> As far as I know, there was no bleaching of my hair by my parents while I
> was sleeping, and I know that I don't dye it now, so the effect seems
> legitimate. Although I have no idea why it happens, I suspect there's a
> genetic component, as pictures of my (naturally brown-haired) mother also
> show her with very light blonde hair as a child.
>
While as sceptical as the next person (possibly even more), I have to
support Jeff on this one and turn an anecdote into data. In short, me
too. I was once blonde (well, sort-of) but no one could accuse me of
that now. And it's not graying that we're talking about (I said, we're
not talking about it!) but a steady darkening with age. My kids too. I
think it's a well-established phenomenon.
And getting back to Tasha's question, I don't have a clue.
(but way back on September 14/99, Jeff Ricker pointed us to Mange and
Mange's 1980 textbook, _Human Genetics_ when we had a similar
discussion. Jeff quoted the Manges as saying "Some pigmentation may
develop over a period of years...The hair may turn from white or
cream-colored in infancy to yellow or red in adulthood...[I guess they
were listing some extremes]. That doesn't explain the phenomenon, but
it confirms it. However, it's well-known (which means I don't have a
handy reference) that some genes only exert their effect late in life
(Huntington's Chorea, for example), so it's only a small stretch to
imagine a more continuous, slowly-developing effect).
-Stephen
------------------------------------------------------------------------
Stephen Black, Ph.D. tel: (819) 822-9600 ext 2470
Department of Psychology fax: (819) 822-9661
Bishop's University e-mail: [EMAIL PROTECTED]
Lennoxville, QC
J1M 1Z7
Canada Department web page at http://www.ubishops.ca/ccc/div/soc/psy
Check out TIPS listserv for teachers of psychology at:
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