A study just published in the American Journal of Physical Anthropology has used the powerful shape-analysis technique of geometric morphometrics to discover that primate crania are quite diverse! Sampling one male and one female from a wide variety of primate genera, the researchers determined the shape-differences among these major groups using 3D landmark coordinates and principle components analysis. Wouldn't you know, that their analysis showed a clear distinction between strepsirhines (lemurs and lorises, the most primitive of all primates) and anthropoids (monkeys and apes, which includes humans). Oh, and humans are markedly different from our ape brethren. So now all those speciesists out there can't claim that, "all primates look alike."
Why is this paper interesting? Um...
Fleagle J, Gilbert C, and Baden A. Primate Cranial Diversity. American Journal of Physical Anthropology, in press.