The –est Paleontology

50-million-year-old fossil sperm discovered

World’s oldest sperm may have come from a leechlike worm

ancient sperm

ANCIENT SPERM  The elongated head and whiplike tail of one of many apparent worm sperm cells studs the wall of a 50-million-year-old cocoon. 

B. Bomfleur et al/Biology Letters 2015

By Meghan Rosen

- More than 2 years ago

Worm sperm have staying power. Embedded in the wall of a fossilized cocoon, mineralized sperm from what may have been a leechlike worm have stuck around for about 50 million years.