The largest birds that ever livedâ€”the now-extinct elephant birdsâ€”looked a lot like super-sized ostriches. They were fast-running and flightless, just like ostriches are. And their island home of Madagascar was just a short distance from mainland Africa, where ostriches live.
If you had to put money on the identity of the elephant birdsâ€™ closest living relative, the ostrich would be a safe bet. It would also be a spectacularly wrong one.
Elephant birds have been extinct for centuries, but many of their skeletons reside in museums around the world. By extracting DNA from these specimens and comparing it to DNA from living birds, Kieren Mitchell from the Australian Centre for Ancient DNA has discovered that the elephant birdsâ€™ closest living relative isâ€¦ the kiwi.
â€œThat blew us away completely,â€ says Alan Cooper, who led the study. â€œYou have to try pretty hard to get a more disparate pair.â€
Heâ€™s not exaggerating. Elephant birds probably plucked fruit from trees, while kiwis rummage through leaf litter for grubs and worms. Elephant birds lived in Madagascar, around 7,000 miles away from the kiwiâ€™s home in New Zealand. The biggest elephant birds great up to 3 metres tall and weighed up to 275 kilograms; kiwis would bump against your shins and smaller species could fit inside an elephant birdâ€™s gargantuan egg.