Now this is quite extraordinary even in nature. Glyptapanteles places it's eggs, about 80, inside hyrinteina leucocerae, butterfly larva. Then eggs turn to larva, which eat their host, and digg outside from host larva. However, the host does not die, but stays alive as a zombie, which now starts to defend it's parasites by hammering possible attackers. 

A parasitized caterpillar stays near the cocoons of the young wasps that burst out of its body. When a potential predator intrudes, the doomed caterpillar sings at it until it leaves. Video courtesy of PLoS One

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