Here's an abstract from a talk I attended at the GSA (Geological Society
of America) conference yesterday. A newpaper article (Oct.27, National
Post, Toronto) on the talk follows.

Cheyenne

----------------------------------------------------

ESTABLISHING THE STABILITY AND STABLE CARBON, NITROGEN AND SULFUR ISOTOPE
COMPOSITION OF ANCIENT HUMAN HAIR: RECONSTRUCTING PALEODIETS

(MACKO, S.A., ENGEL, M.H., ANDRUSEVICH, V.E., LUBEC, G., O'CONNELL, T.C.
AND HEDGES, R.E.)

The application of stable isotopes for reconstructing the diets of
ancienct human populations has focused primarily on the analysis of bone
collagen. Collagen, however, is problmatic, owing to its lack of long term
stability and uncertainties as to whether the stable isotope compositions
of its decomposition products reliably reflect that of the original
biomolecule. Alternatively, the stable carbona and nitrogen istope
compositions of modern hari obtained from large cross sections of human
populations have been found to be reliable indicators of trophic level and
prinicipal type of vegetation (C3 or C4) consumed, respectively. Analyses
of hair subjected to simulated aging and of ancient hair clearly indicate
minimal alteration of the B-keratin protein that comprises it. Amino acid
distributions remain relatively constant and amino acid racemization is
miniaml in samples up to 5200 years old. The high sulfur content of
B-keratin permits its further assesssment of marine vs terrestrial dietary
influence based on stable sulfur isotopes..
        Here we report paleodietary recontructions for several ancient
populations. For example, the Coptics of Egypt (1000 BP) and Chinchorro of
Chile (5000 BP to 700 BP) exhibit diets of similar diversity to that
observed for modern (i.e. supermarket diets) populations, but were
influenced by local nutritional sources. Egyptian Late Middle Kingdom
mummies (~4000 BP) have a more uniform isotopic signature, indicating a
more constant diet. The Neolithic Ice Man of the Oetztaler Alps (5200 BP)
had a primarily vegetarian diet. It appears that hair, often overlooked in
archeological sites, affords an excellent proxy for paleodietary
reconstruction.

--------------------------------------------------------------

"The hair-raising truth about our diet" (by Aisling Irwin, National Post,
Oct.27, 1998, Toronto)

Otze the Ice Man, the 5,000 year old corpse discovered six years ago in an
Alpine glacier, was most likely a vegan.
        Analysis of his hair has revealed that his diet was lacking in
meat and dairy products.
        "YOu are what you eat, and clues to what people ate thousands of
years ago are stored in their hair", said Stephen Macko, professor of
environmental science at the University of Virginia.
        The finding is part of a research program to unlock the secrets of
ancient lives from their hair. The neolithic Ice Man was discovered in the
Oetztaler Alps between Austria and Italy and thought by some to be a
hunter, particularly since he carried a bow and an axe.
        But the arrows were not finished, and the bow was unstrung.
        Prof. Macko's team used hair analysis, which exploits a natural
difference in teh types of elements present in different foods. It also
takes advantage of the fact that hair does not decay to the extent that
bone or flesh does. "it is a terrific archive of information,", Prof.
Macko told the annual meeting of the Geological Society of America, in
Toronto. "Today's breakfast is next week's hair".
        Scientists test the hair for its carbon, nitrogen and sulphur
content and then analyze each of these elements to see what proportions
they contain of their natural variants, or stable isotopes. Different
food sources - for example vegetable compared to meat - contain different
proportions of these isotopes. But Prof. Macko agreed that hair could
reflect only the diet of the previous few months.
        He also told yesterday's conference of work on 1,000 year old
hairs from the Copts of Egypt, on hair from the Late Middle Kingdom
mummies of Egypt and from the Chinchorro mummies of Chile. The Chincorro
had unexpected evidence of a seafood diet in their hair, despite the fact
that they lived well inland in the Atacama desert.