Three-dimensional molar enamel distribution and thickness in Australopithecus and Paranthropus.
Biol Lett
; 4(4): 406-10, 2008 Aug 23.
Article
in En
| MEDLINE
| ID: mdl-18522924
ABSTRACT
Thick molar enamel is among the few diagnostic characters of hominins which are measurable in fossil specimens. Despite a long history of study and characterization of Paranthropus molars as relatively 'hyper-thick', only a few tooth fragments and controlled planes of section (designed to be proxies of whole-crown thickness) have been measured. Here, we measure molar enamel thickness in Australopithecus africanus and Paranthropus robustus using accurate microtomographic methods, recording the whole-crown distribution of enamel. Both taxa have relatively thick enamel, but are thinner than previously characterized based on two-dimensional measurements. Three-dimensional measurements show that P. robustus enamel is not hyper-thick, and A. africanus enamel is relatively thinner than that of recent humans. Interspecific differences in the whole-crown distribution of enamel thickness influence cross-sectional measurements such that enamel thickness is exaggerated in two-dimensional sections of A. africanus and P. robustus molars. As such, two-dimensional enamel thickness measurements in australopiths are not reliable proxies for the three-dimensional data they are meant to represent. The three-dimensional distribution of enamel thickness shows different patterns among species, and is more useful for the interpretation of functional adaptations than single summary measures of enamel thickness.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Hominidae
/
Dental Enamel
/
Molar
Limits:
Animals
Language:
En
Journal:
Biol Lett
Journal subject:
BIOLOGIA
Year:
2008
Document type:
Article
Affiliation country:
Alemania