Researchers use advanced imaging techniques to see what happens when a male and a female mate.

As robust efforts fail to reproduce findings of influential zebra finch studies from the 1980s, scientists discuss ways to reduce bias in such research.

Some beetle species may have evolved to tunnel into the ground to escape the pathogens that abound on dead and rotting animals.

Host slugs given Prozac to increase their serotonin levels no longer avoid parasitic nematodes, the same behavior seen in infected slugs.

Researchers whose work requires that they draw blood from wild animals are finding unlikely collaborators in biting insects.

An assassin bug, which some researchers are using as living syringes to sample blood from birds and mammals, feeds on a bat.

Filter-feeders emerge as potential defenders against a deadly amphibian disease.

Blue badges that make female lizards less attractive to potential mates are paradoxically common.

Female spiders prefer sperm from males with gifts, a study shows.