What doesn’t kill you makes you stronger. The saying couldn’t be more true for the whitefly (Bemisia tabaci, pictured), a pest that feeds from toxic plants like tobacco. Scientists found that a gene in the bug, responsible for blocking natural pesticides, came from a plant about 35 million years ago, The Scientist reports. This is one of the first known cases of functional gene transfer between plants and animals, the team reports this week in Cell. The researchers suspect the gene got into the insect’s genome when a whitefly ate a plant that had this gene and was infected by some virus. The virus would have incorporated the plant’s genetic material and inserted it into the bug’s DNA.
*Correction, 2 April, 2 p.m.: A previous version of this story said this was the first case of a gene transfer from plants to animals. Other studies have identified similar transfers, though they did not show the genes were functional.