It's the beginning of the spooky season, which means ghouls, ghosts, and bloodsuckers abound. One of the most famous bloodsuckers in nature is, of course, the leech. These parasites feed on blood and ...

A newly described fossil reveals that leeches are at least 200 million years older than scientists previously thought, and that their earliest ancestors may have feasted not on blood, but on smaller ...

You might think you know leeches: Go for a swim in the wrong shallow lake, and you’ll emerge covered in sleek black bloodsuckers that have decided you’re their next meal. But inside a leech, ...

The fossil leech compared with a modern leech. Double arrows indicate the large caudal sucker used for attachment, single arrows indicate body annulations. A newly described fossil reveals that ...