Dear Richard,

I've received your letter concerning the "Oldest Shell Beads" already
several times but it seems that you never got my answer. Since I'm one of
the six authors, who wrote the original article (Middle Paleolithic Shell
Beads in Israel and Algeria. Science, 312: 1785-1788 + additional
information - 3 pages - of supporting material Online) and not of the
numerous brief stories, which appeared in newspapers all over the world, I
will give some personal comments.



I doubt whether you have read the complete story. The finds of beads of
Nassarius gibbosulus in the Ahmarian layers of Ucagizli, Turkey, were dated
to ~40 ka i.e. 40.000 years B(efore)P(resent), see Kuhn et al. 2001. Proc
Nat. Acad. Sci., 98: 7641. The 41 beads made of shells all belonging to
Nassarius kraussianus and found in the Blombos Cave in South Africa turned
out to be 75ka old.

The two shell beads from Skhul were found in layers which were dated
100-135ka. In order to be at the sure side we wrote that the beads are
100.000 years old (but we don't rule out that they may be even 135.000 years
old!).



The age of the shells from Skhul agree exactly with that of the so-called
Tyrrhenian period of the Mediterranean. This was not a cold glacial period
but the last, warm interglacial period, which lasted between about 135-90 ka
BP. That period was warmer then the current situation in the Mediterranean
Sea, and allowed such species as Strombus bubonius (now Lentigo latus) to
live in the Mediterranean. The latter is even used as an index fossil for
the Tyrrhenian stage. Today it is confined in its distribution to West
Africa. However, most of the Tyrrhenian species are still living in the
Mediterranean Sea, although sometimes you can find some minor changes in
form and size. For example the heavier development of the parietal callous
in Nassarius gibbosulus, which is indeed secreted by a part of the mantle,
increased the width of Tyrrhenian specimens compared to recent ones. This
callous is also usually covering the top of the shell in Tyyrhenian ones and
never in recent ones (however it does so in the closely related
Mediterranean Nassarius circumcinctus).

During the Tyrrhenian stage Cowries were living in the Mediterranean Sea and
were available to the people of Skhul, however, no shell beads made from
Cowries have been found during the excavation of Skhul.

I don't think that Nassarius, whether gibbosulus or kraussianus, can be
considered as merely local substitutes for Cypraea moneta. The massive
exploitation of Cypraea moneta (and Cypraea annulus) took place at a much
later stage in modern human history. However, in the Levant local species of
Cowries have been used as shell beads since the Epipalaeolithic period
(23-14.5 ka BP see Bar-Yosef Mayer, 2005. Paleorient, 31: 176-185, and
references in it).



Henk K. Mienis

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