Just found this on the intertubes. It’s a fascinating (and creepy) YouTube video about nematomorpha, parasitic creatures more commonly called “hairworms.” We wrote a short piece about them in Uncle John’s Triumphant 20th Bathroom Reader (2007, p. 172). An excerpt:

Tests on grasshoppers that had contracted hairworms by drinking water containing hairworm larvae revealed that the lavrae feed off grasshoppers’ insides and grow until one takes up most of its body cavity. When that worm is ready to reproduce, it secretes a protein concoction that affects the grasshopper’s central nervous system, mimicking messages to its brain. The messages drive the grasshopper to water, where it doesn’t stop for a drink…it jumps in and drowns. It is effectively induced to commit suicide. The worm, which by this time can be three times the length of the grasshopper, then crawls out of the carcass and swims off to find a mate.

Yum!

Related Extra: A fungus that brainwashes ants into sacrificing themselves…for the fungus.

And this just in: Yay toads!