Related Experiment Video
Updated: Jun 8, 2026

Reverse Dissection and DiceCT Reveal Otherwise Hidden Data in the Evolution of the Primate Face
Published on: January 7, 2019
An enlarged postcranial sample confirms Australopithecus afarensis dimorphism was similar to modern humans
Philip L Reno1, Melanie A McCollum, Richard S Meindl
1Department of Developmental Biology, Stanford University School of Medicine, 279 Campus Drive, Beckman 300, Stanford, CA 94305-5329, USA. preno@stanford.edu
Abstract:
In a previous study, we introduced the template method as a means of enlarging the Australopithecus afarensis postcranial sample to more accurately estimate its skeletal dimorphism. Results indicated dimorphism to be largely comparable to that of Homo sapiens. Some have since argued that our results were biased by artificial homogeneity in our Au. afarensis sample. Here we report the results from inclusion of 12 additional, newly reported, specimens. The results are consistent with those of our original study and with the hypothesis that early hominid demographic success derived from a reproductive strategy involving male provisioning of pair-bonded females.
More Related Videos
08:03Midface Hypoplasia and Cranial Base Morphology in Syndromic Craniosynostosis: A Comparative Analysis Study Using a Predictive Regression Model
Published on: November 4, 2025
07:26Systematic Assessment of Mammalian Skull Specimens for Dental and Temporomandibular Joint Pathology
Published on: August 22, 2022
Related Concept Videos
Synteny and Evolution
Around 80 million years ago, the human and mice lineages diverged from the common ancestor. During the course of evolution, the ancestral chromosome underwent...
Convergent Evolution
The Evidence for Evolution
Cranial Bones: Superior and Posterior View
The frontal bone is the single bone that forms the forehead. At its anterior midline, between the eyebrows, there is a slight depression called the glabella. The frontal bone also forms the supraorbital margin of the orbit. Near the middle of this margin is the supraorbital foramen, the opening that provides passage for a sensory nerve to the forehead. The frontal bone is thickened just above each supraorbital margin,...
Testing a Claim about Mean: Unknown Population SD
Estimating a population mean requires the samples to be approximately normally distributed. The data should be collected from the randomly selected samples having no sampling bias. There is no specific requirement for sample size. But if the sample size is less than 30, and we don't know the population standard deviation, a different approach is used; instead...
Evolutionary Psychology