“They are impressive pieces of research,” says Marcus Kronforst, an evolutionary biologist at the University of Chicago in Illinois who was not involved with either group. He notes that these studies are rare examples where researchers verified the mutations responsible for a trait by making them in another species.
Milkweed plants produce compounds called cardiac glycosides, which disrupt molecular pumps that control the proper flow of ions in and out of cells. Monarch butterflies and other consumers of the plant, however, have evolved versions of these pumps that leave the animals unaffected. To find what changes these milkweed eaters had in common, Noah Whiteman, an evolutionary biologist at the University of California, Berkeley, and his colleagues recently matched up the gene for this molecular pump in 21 insects, including monarchs, that tolerate the plant to varying degrees.
Read on: https://www.sciencemag.org/news/2019/10/how-monarch-butterfly-evolved-its-resistance-toxic-milkweed?utm_campaign=news_daily_2019-10-02&et_rid=389253831&et_cid=3013912