Imagine you're an ant, going about your day & minding your own business, when all of a sudden you start to feel a little strange. You try to walk down an innocent looking tree, but instead your brain makes you walk up. You don't know what's going on, so you turn to your colony for assistance. They'll know what to do, right? Well it turns out, they do, and quickly drag you as far away from the nest as they can so that you don't infect anyone else. Now you know there's a real problem, which isn't helped when you start to feel a movement inside your tiny exoskeleton. Then, all of a sudden, it all goes black and a weird, alien creature bursts out of your body. R.I.P. Mr. Ant.
|Cordyceps infected bee (Photo: Erich G. Vallery, USDA Forest Service)|
Whilst that might sound like the plot of a bad B movie, it's actually a (very simplified) version of a real phenomenon. It isn't in fact an alien creature, but a genus of parasitic fungi called cordyceps that attack insects by infecting them with their spores. The spores grow inside the unfortunate bugs until they eventually explode out, causing the death of the effected creature.
There are literally hundreds of different species of cordyceps, each adapted to prey on individual types of insects. One species, cordyceps unilateralis, implants its spores into unsuspecting insects, infecting their brains and causing them to become living zombies. The cordyceps then forces them to walk as high up into the trees as they can, which goes against their natural behaviour. This ensures that the parasite's spores will spread over the widest area possible when they eventually burst out. Creepy stuff!