Evolution

The mathematical concept of parity and the fatal flaw of serial multiplication can help explain why having two sexes usually works better than having one or three.

Sex might help natural selection purge excessive mistakes from our genes.

Asexual reproduction can produce twice as many offspring as sexual reproduction without the hassle of finding and courting a mate. So why do most complex animals have two sexes? Why not three?

The evolutionary biologist Jessica Flack seeks the computational rules that groups of organisms use to solve problems.

If gut bacteria can sway their hosts to be selfless, it could answer a riddle that goes back to Darwin.

An unexpected mechanism allows wasps to rapidly co-opt genes for new toxic functions.

A definitive explanation for why plants evolved spines remains elusive, and human biases compound the problem.

How Darwinian natural selection can produce and sustain a Lamarckian “inheritance of acquired characteristics.”

Spiders appear to offload cognitive tasks to their webs, making them one of a number of species with a mind that isn’t fully confined within the head.