The Nocturnal Kiwi Bird

Instead of shivering while we think about winter, let's contemplate a bird who lives where it's summer right now: New Zealand's kiwi bird.  

There are five species of kiwi, all of them endangered, all of them flightless. They have no tail, only rudimentary wings, and nostrils at the end of their long, slender bills. As if those traits aren't weird enough, they are also nocturnal. We here at Talkin' Birds wonder whether they ever star in New Zealanders' ghost stories, but never mind.

Kiwis emerge from caves in the evenings to forage for food. Perhaps because they're active at night, they have lost their color vision and have gained an acute sense of smell. Interestingly, they also have a lower body temperature and slower metabolism than other birds. 

Fewer than 3% of the world's bird species are nocturnal. Researchers from the University of Leipzig and Max Planck Institute for Evolutionary Anthropology estimate that the kiwi became nocturnal about 35 million years ago, after its ancestors came to New Zealand. Why? They're not sure, but perhaps other bird species crowded them out of daytime food resources and they had to adapt. These researchers have sequenced the kiwi genome for the first time ever. Their findings recently appeared in Genome Biology, so take a look.