Mj. Kohn et al., VARIABILITY IN OXYGEN-ISOTOPE COMPOSITIONS OF HERBIVORE TEETH - REFLECTIONS OF SEASONALITY OR DEVELOPMENTAL PHYSIOLOGY, Chemical geology, 152(1-2), 1998, pp. 97-112
Oxygen isotope compositions of herbivore tooth enamel from two areas i
n Kenya were measured using a laser fluorination approach. Isotope het
erogeneity was found within four sets of teeth in the jaws of differen
t individuals (similar to 2 parts per thousand), as well as within ind
ividual teeth. The rear molar (M3) of a zebra shows a 1.4 parts per th
ousand variability, whereas, the middle and rear molars (M2 and M3) of
a gazelle show variations of 1.7 to 2.9 parts per thousand. The front
molar (M1) of a gazelle is relatively homogeneous (similar to 0.25 pa
rts per thousand). Compositional heterogeneities are spatially correla
ted, and comparison to theoretical models suggests that they largely r
eflect different times of tooth growth coupled with seasonal changes i
n forage composition, rather than developmental physiology. Spatially-
specific enamel analysis combined with knowledge of genus-specific die
t, water turnover, and physiology allows paleoclimate seasonality to b
e assessed. (C) 1998 Elsevier Science B.V. All rights reserved.