Meet the leech, the misunderstood hero of aquatic ecosystems all over the world, who does not always suck blood!

Learn about a 480-million-year-old leech fossil that revealed that ancient leeches didn’t have the biological components necessary to suck blood.

The first time I was bitten by a leech, I was swimming in a West Virginia river. I remember the scene perfectly: I crawled ...

Scientists found a 430-million-year-old leech fossil, Macromyzon siluricus. It shows leeches first lived in oceans and did ...

How do leeches find their hosts? We explore how leeches sense heat, chemicals, and movements in their environments.

A 430-million-year-old fossil has rewritten leech history, showing they are at least 200 million years older than previously ...

Scientists have also long thought that the earliest leeches were bloodsuckers. All modern leeches, including species that do ...