Linked Life Data

10879652

Source:http://linkedlifedata.com/resource/pubmed/id/10879652

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2000-10-2
pubmed:abstractText
In the assessment of human origins, chimpanzees (Pan troglodytes, henceforth called Pan) represent the best hominoid outgroup for comparisons. Such an outgroup roots the "anatomically modern" human population cluster, or continuum. This study incorporates chimpanzees into a worldwide modern human database of quantified complete tooth variables (approximately 30 per tooth; e.g., root, pulp, enamel) in an attempt to develop a more accurate phylogeny of the hominoid continuum, with only intervening extinct hominids missing. Canonical discriminate analysis was performed mainly among Liberian common chimpanzees and global samples of humans. The first canonical variable explained 70% of the total variance and showed a tight cluster of humans, with chimpanzees as a distant outgroup. Within the human community, first non-San Bushman, sub-Saharan Africans and Andamanese, and then, close in, Australian aborigines were positioned towards Pan. Their relative orientation suggested an African human origin with the first branch within sub-Saharan Africa: sub-Saharan Africans and San Bushmen. Next, Andamanese Negritos, and then Australian aborigines, formed the early first surviving modern human lineage to leave Africa. Thin enamel and big teeth with relatively large roots characterized Pan nonmolar teeth. Humans showed a generalized sexual dimorphism for all teeth, with males having bigger teeth, bigger relative roots, and thinner enamel than females, while only Pan canines had significant and impressive sexual dimorphism. Interestingly, Pan molars were not larger than human molars. The data suggest that although hominids underwent two dental macroevolutionary events, the lineage leading to modern humans only experienced anterior tooth-size reduction. The suggested evolutionary significance of the observed total tooth variation is discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:issn
0270-4145
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1-9
pubmed:dateRevised
2010-11-18
pubmed:meshHeading
pubmed:articleTitle
Chimpanzees as an outgroup for the examination of human dental evolution.
pubmed:affiliation
Department of Oral Biology, Faculty of Dentistry, McGill University, Montreal, Quebec, Canada. shields@med.mcgill.ca
pubmed:publicationType
Journal Article, Comparative Study