How the octopus got its grip: an ancient gene, borrowed for a brand-new job

An octopus shares an ancestor with the garden snail — so how did it end up with arms lined with powerful suckers? Researchers at the University of Tokyo, led by postdoctoral fellow Ryosuke Kimbara, compared developing cuttlefish, octopus and snail embryos and found evolution's favourite trick: reuse. The suckers were not built by the genes that pattern arms; instead they switch on Ets1, a gene normally busy in the earliest days of a mollusc embryo, and put it to work building a grip. Published in iScience, the work shows new inventions in nature often start as old tools, borrowed.