Parasites Make Caterpillars Glow to Repel Predators

Parasitic worms may be saving their own little hides when they induce the caterpillars they infest to glow a little and blush a furious red.

As the parasitic nematode Heterorhabditis bacteriophora infects caterpillars of the greater wax moth, the normally pale caterpillars temporarily bioluminesce and also turn persistently pink-red.

In outdoor taste tests with 16 European robins, birds overall preferred uninfected waxmoth caterpillars to ones that had been infected for at least three days. By the seventh day of infection, odd-colored caterpillars barely even got tentatively picked up by the birds.

It’s to the parasite’s advantage not to be eaten because these nematodes don’t infect vertebrates. So if a bird happens to eat a parasitized caterpillar, it’s bye-bye wormy.

Read more in the original article here.