If you’re looking for a creepy science lesson, check out parasitism in nature.
There’s a type of fungus that takes over an ant and causes the ant to crawl up a branch and latch on, where the fungus grows and spreads. Different types of fungus can attack different animals.
Wikipedia has an entry. The Atlantic and National Geographic also have articles.
National Geographic has a short video about this.
BBC has another video about this.
Deep Look has a good video about a fungus that attacks a fruit fly.
But ants don’t always get a raw deal from fungus. Some types of ants farm fungus for food (Deep Look again):
There’s also a parasitic worm that takes over a snail and causes the snail to turn into a colorful and easy-to-grab treat for birds. Then the worm reproduces inside the bird. See Wikipedia or Wired for articles, or see National Geographic for a video.
National Geographic also has a video about a type of wasp that invades a caterpillar.
MoMooMath offers various examples of parasitism.
StoneAgeMan has a video about mutualism, commensalism, and parasitism.
Image: Gilles San Martin