A gene interferes with the caterpillar's molting hormone and influences the insect's desire to climb. A single gene in a caterpillar virus sends its victims running for the treetops, where they die and their bodies liquefy, sending an ooze of virus particles on their brothers and sisters below. This species of baculovirus infects only gypsy moth caterpillars, essentially turning them into zombies. It stops the caterpillars from molting and sends them up into the tree leaves during the day (a behavior they normally save for the cover of darkness), where they die among the leaves as they wait to molt.
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