whom I have discussed the matter to
speculate that these oro-facial patholo-
gies might be a major contributor to
an early death. Gejvall's comment that
severe attrition and the sequelae of
infection were probable causes of
death is therefore most welcome.

Significant among the variables of
tooth wear are the properties of the
tooth tissues themselves. The chemical
composition of the substances chewed
is also likely to influence the rate of
wear, as pointed out by Van Valen and
Dewey. Only a few studies, of a limited
nature, have been carried out to inves-
tigate this question of changes in the
oral environment. It is useful, there-
fore, to learn of the investigations de-
scribed by Van Valen which report a
constant rate of enamel loss in bats and
laboratory rats.

During my work on tooth wear, I
came across several excellent papers
on the microstructural quality of teeth
(Bradford 1960, Kraus 1969, Nalban-
dian, Gonzales, and Sognnaes 1960,
Sognnaes 1956). Sognnaes proposed
that the tooth is a sensitive indicator of
the developmental quality of the or-
ganism and especially of the calcifying
properties of the diet. Kraus agreed
and pointed out that the extended
embryonic period of tooth develop-

References Cited

ANDERSON, JAMES E. 1965. Human skele-
tons of Tehuac5n. Science 496-97.

ARA°, E. M. 1969. Amilise do material

Osseo humano do Sambaqui do Rio Les-
sa. Anais do Instituto de Antropologia da
Universidade Federal de Santa Catarina

2:179. [MJP*1 BARRETT, M. J. 1958. Dental observations

on Australian Aborigines: Continuously
changing functional occlusion. Australian
Dental Journal 3:39-52. [MJB*]

1969. Functioning occlusion. An-
nals of the Australian College of Dental
Surgeons 2:68-80. [MJB*J
BARROWS, DAVID PREscorr. 1967. The eth-

no-botany of the Coahuilla Indians of South-
ern California. Banning: Malki Museum
Press.

BASTOS DE AVILA, J. 1958. Antropologia
fisica (Introducao). Rio de Janeiro: Agir.

[MJP*]

BEGG, P. R. 1938. Progress report of ob-
servations on attrition of the teeth in its

relations to pyorrhoea and tooth decay.
Australian Journal of Dentistry 42:315-20.

[MJB*]

1954. Stone Age man's dentition
with reference to anatomically correct
occlusion, the etiology of malocclusion,
and a technique for its treatment. Ameri-
can Journal of Orthodontics 40:298-312.

[MJB*]

BOULE, MARCELLIN, and HENRI V. VALLOIS.
1957. Fossil men. London: Thames and

Hudson.

BRABANT, H., and A. SAHLY. 1962. La pa-
leostomatologie en Belgique et en

France. Acta Stomatologica Belgica 59:285.
BRABANT, H., and F. TWIESSELMANN. 1964.

524

ment makes tooth microstructure a
vital record of many life crises. Taking
these observations as a lead, I pro-
posed to look at the tooth as an organ
that is highly adaptive and capable of
responding to a variety of environ-
mental stresses. Among these is, of
course, mechanical stress and the re-
sulting abrasion, with the deposition of
secondary dentine as part of the re-
sponse sequence. Other responses can
be seen upon examination of the
microstructure of the dentine-prin-
cipally sclerosis of dentinal tubules, as
I have reported elsewhere (Molnar
1971 b, Molnar and Ward n.d.).

These changes in dentine will affect
the rate of wear, but individual capaci-
ty to respond, or, rather, the state of a
person's mineral metabolism, is the
critical factor, so Gejvall's comments
are very appropriate for a paper on
dental attrition. In particular, I think
his description of the lack of secondary
dentine in the Westerhus population is
especially significant, and the specula-
tion that hypomineralization (due to
D-avitaminosis or ?) may be one of the
underlying causes should be carefully
noted. Gejvall also describes the ap-
pearance in this population of Harris
lines in tibiae. In my opinion, the
quality of hard tissues can provide

Observations sur revolution de la den-
ture permanente humaine en Europe
occidentale. Bulletin du Groupe Interna-
tional des Recherches Scientifiques en Sto-
matologie 7:11-84.

BRACE, C. L. 1964. The fate of the Classic
Neanderthal: A consideration of homi-

nid catastrophism. CURRENT ANTHRO-
POLOGY 5:3-46.

BRACE, C. LORING, and PAUL E. MAHLER.
1971. Post-Pleistocene changes in the

human dentition. American Journal of Physical Anthropology 34:191-204.

[CLB,MHW*]

BRACE, C. L., and STEPHEN MOLNAR. 1967.
Experimental studies in human tooth

wear I. American Journal of Physical An-
thropology 27:213-22.

BRADFORD, E. W. 1960. The dentine, a
barrier to caries. British Dental Journal

109:387-98.

BROSE, DAVID S., and MILFORD H. WOL-
POFF. 1971. Early Upper Paleolithic man

and late Middle Paleolithic tools. Ameri-
can Anthropologist 73:1156-94.

[DSB,GAW,MHW*]

BROTHWELL, D. R. 1963a. "Macroscopic
dental pathology of humans," in Dental

anthropology. Edited by D. R. Brothwell,
pp. 20-89. New York: Pergamon Press.

1963b. Digging up bones. London: British Museum.

BUXTON, L. H. DUDLEY. 1920. The teeth
and jaws of savage man. Transactions of

the British Society for the Study of Orthodon-
tics 1916-1920: 79-88.

CAMPBELL, BERNARD. 1966. Human evolu-

tion. Chicago: Aldine. [SR*]
CAMPBELL, T. D. 1925. Dentition and palate

of the Australian Aboriginal. Adelaide:
Hassell Press. [MJBi]

invaluable information about diet, dis-
ease, and the general state of health of
the individual and hence the ecological
position of the whole population. The
teeth are especially sensitive indicators
of the many environmental variables
that affect mineralization in the sys-
tem. Microstructural analysis together
with dental attrition studies can pro-
vide vital records if only we can learn
to read them, and these records are of
considerable time depth, a condition
which is lacking in studies of so many
other biological features.

My work, which started with investi-
gations of human chewing motions
and experimentally produced wear
patterns, has now led to the problem
of discrete changes in tooth enamel,
dentine, and cementum. This paper
discusses only a single facet: gross
structural changes in response to cul-
tural factors. I hope the reader, like
the commentators, will appreciate the
numerous interrelated factors in-
volved in dental-environmental rela-
tionships. The challenge is there, the
research possibilities are endless, and
the returns in terms of information
about evolutionary processes are very
great. More work is needed in all areas
discussed in the paper, the comments,
and this reply.

. 1938. Observations on the teeth of Australian Aborigines. Australian Journal of Dentistry 42:41-47.

. 1939a. Food, food values and food
habits of the Australian Aborigines in
relation to their dental conditions. Part I.
Australian Journal of Dentistry 43:2-15.

. 19396. Food, food values and food
habits of the Australian Aborigines in
relation to their dental condition. Part II.
Australian Journal of Dentistry 43:45-55.

. 1939c. Food, food values and food
habits of the Australian Aborigines in
relation to their dental conditions. Part
IV. Australian Journal of Dentistry

43:141-56.

. 1939d. Food, food values and food
habits of the Australian Aborigines in
relation to their dental conditions. Part

V. Australian Journal of Dentistry 43: 177-

99.

1956. Comparative human odon-
tology. Australian Dental Journal 1:26-29.

[MJB*]

CLARK, W. E. LE GROS. 1964. Fossil evidence
for human evolution. Chicago: University

of Chicago Press.

1967. Man-Apes or Ape-Men? The discoveries in Africa. New York: Holt, Rinehart and Winston.

COLLINS, HENRY B. 1932. Caries and

crowding in the teeth of the living Alas-
kan Eskimo. American Journal of Physical Anthropology 16:451-62.

COON, CARLETON S. 1966. The origin of

races. New York: Alfred A. Knopf.
CRIM, DONALD E., and STANLEY RHINE.

1971. Touching on human evolution.
Paper presented at the Annual Meeting
of Rocky Mountain Social Science As-
sociation, Ft. Collins, Colo., April 7,
1971. [SR r]

CURRENT ANTHROPOLOGY