M. Ridley, PELVIC SEXUAL DIMORPHISM AND RELATIVE NEONATAL BRAIN SIZE REALLY ARE RELATED - BRIEF COMMUNICATION, American journal of physical anthropology, 97(2), 1995, pp. 197-200
Primate species in which the neonatal brain size is large relative to
the birth canal tend to have more sexually dimorphic pelves: this is a
classic comparative relation, discovered by Schultz and Leutenegger.
The original work did not correct for phylogenetic nonindependence of
the data points; it only partly corrected for body size; it used ratio
s in both variables, and the size of the female pubis featured in both
x- and y-variables. A recent publication by Tague placed a question m
ark over the validity of the relation. I therefore retested it, correc
ting for all four statistical defects. A strongly significant statisti
cal relation exists. (C) 1995 Wiley-Liss, Inc.