Pervasive genetic integration directs the evolution of human skull shape

MARTÍNEZ ABADÍAS, NEUS; ESPARZA, MIREIA; SJOVOLD TORSTEIN,; GONZÁLEZ JOSÉ, ROLANDO; SANTOS MAURO,; HERNÁNDEZ, MIQUEL; P KLINGENBERG, CHRISTIAN

EVOLUTION

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2012 vol. 66 p. 1010 - 1023

0014-3820

It has long been unclear whether the different derived cranial traits of modern humans evolved independently in response toseparate selection pressures or whether they resulted from the inherent morphological integration throughout the skull. In anovel approach to this issue, we combine evolutionary quantitative genetics and geometric morphometrics to analyze genetic andphenotypic integration in human skull shape.We measured human skulls in the ossuary of Hallstatt (Austria), which offer a uniqueopportunity because they are associated with genealogical data. Our results indicate pronounced covariation of traits throughoutthe skull. Separate simulations of selection for localized shape changes corresponding to some of the principal derived charactersof modern human skulls produced outcomes that were similar to each other and involved a joint response in all of these traits.The data for both genetic and phenotypic shape variation were not consistent with the hypothesis that the face, cranial base, andcranial vault are completely independent modules but relatively strongly integrated structures. These results indicate pervasiveintegration in the human skull and suggest a reinterpretation of the selective scenario for human evolution where the origin ofany one of the derived characters may have facilitated the evolution of the others.