How did the dairy cow get its spots?

Most dairy cows in New Zealand are Friesians—the ones with black spots dappling white backs and bellies. Figuring out which genes dictate these markings was particularly devilish, but after analysing thousands of coat patterns, an international team of scientists have done it, publishing their findings in Science Advances. It was like winning a race, says animal geneticist Matt Littlejohn, a professor at Massey University. He says the payoffs are more than aesthetic: fiddling with these genes could let farmers avoid markings that can lower a crossbred cow’s value. And if a cow could be draped in more black, that could protect her from sunburn (although it could also make her hotter). But the extent of these tweaks will be determined by how spots fall naturally—so no, we’re not going to see a dairy herd tricked out in corporate branding any time soon, Littlejohn says with some relief.