Honorable Mention / 2022 / Nature / Wildlife

Tapeworm

The “circular-saw-like” structure on the head, or scolex, of this tapeworm develops in the liver of a hare (European Brown Hare, Lepus europaeus), after the hare has unwittingly eaten a tapeworm egg.
If a fox or a dog then preys upon an infected hare, these "saw-blades" come into their own and anchor the tapeworm into the undulating wall of the predator’s small intestine. The adult tapeworm sheds self-fertilised eggs every time the fox or dog defecates. If a hare grazes on grass contaminated by infected faeces, the lifecycle of Taenia pisiformis starts all over again.