Cuckoo catfish trick cichlids into caring for their eggs in a strategy known as brood parasitism.

Parasitoid wasps inoculate other insects with their eggs, and their offspring then grow to feed on their "homes," effectively sucking the life out of their dying hosts.

When it comes to thwarting roundworms, scientists find that combining four antiparasitic drugs in smaller doses packs a greater punch than the four drugs alone.

The first global evaluation of populations demonstrates that certain species are diminishing considerably.

The plant Lophophytum pilfers mitochondrial genes from the species it parasitizes.

Crypt keeper wasps appear to command crypt gall wasps to dig exit tunnels on their behalf.

Ideas abound for why some animal species sleep so much more than others, but definitive data are elusive.

Researchers find Oriental rat fleas, the insects that can carry plague bacteria, on New York City-dwelling rodents.

Toxoplasma gondii seems to cause hard-wired changes in the brains of mice that persist even after the parasite is gone.

An ant species that lives on a carnivorous pitcher plant keeps nutrient thieves from escaping by eating them.