It's like weird Parasites
2. One in the eye
This parasitic flatworm makes snails behave very strangely. As dawn breaks the normally light-shy snails become attracted to the sun and climb up plants where they can be seen by hunting birds.
The flatworm has also invaded their eye stalks to make them swell up and pulse with vibrant colours that look like a tasty caterpillars. Hungry birds then swoop down, eat the snail and give the parasite a new home in their rectum. Eggs are produced here and pushed out with the bird’s poo.