If we look across the whole of the mammal branch of the tree of life, we find there are many groups of mammals that have evolved testicles of all different sizes. In almost all these separate cases, ...

The human body is a machine whose many parts—from the microscopic details of our cells to our limbs, eyes, liver and brain—have been assembled in fits and starts over the 4 billion years of our ...

The evolution of the human species is marked by an increase in brain size. Now new research suggests that could be partly dependent on increases in prenatal estrogen—revealed by looking at the length ...

(Volodymyr Yakimchuk/Creatas Video+/Getty Images Plus) A seismic shift in the selection pressures acting on humans may have ...

Share on Pinterest Human brain cell evolution may be linked to autism, neurodiversity, according to a new study. Image credit: Lauren Lee/Stocksy A new study concludes that the speed at which the ...

(THE CONVERSATION) Most people know only two things about the appendix: You don’t need it – and if it bursts, you need surgery fast. That basic story traces back at least to Charles Darwin, the ...