Long before Western astrology, the Chinese zodiac helped organize years, beliefs, and social life. Here’s how the system of 12 animals evolved over the centuries.

An ancient and enormous organism called Prototaxites, initially found to be a type of fungus, may actually be an unknown ...

Such evidence suggests early heartworms evolved alongside canines millions of years ago. Mosquitoes existed long before ...

Their trunklike fossils were discovered in 1843. Yet despite more than a century of speculation, scientists have struggled to answer the most basic question about Earth’s original terrestrial giants: ...

Dog owners are often advised to prevent heartworm infections with drugs called parasiticides, but their widespread use has ...

Heartworm disease is caused by the parasite Dirofilaria immitis. It is spread to dogs by mosquitoes and can be fatal. Adult ...