Bigger brains led to bigger bodies in our ancestors

New research suggests that humans became the large-brained, large-bodied animals we are today because of natural selection to increase brain size. The work contradicts previous models that treat brain size and body size as independent traits. Instead, the study shows that brain size and body size are genetically linked and that selection to increase brain size will ‘pull along’ body size.
Paleontology News — ScienceDaily