Several million years ago, a small bird flew to New Zealand. Arriving there, it found few threats and plenty of opportunities. In the absence of mammals, its descendants gradually lost the ability to fly, as island birds are wont to do. They also evolved to fill those niches that mammals typically occupy, rootling around the leaf litter in search of worms and grubs. They transformed into that icon of New Zealand—the adorable, bumbling kiwi.

Or rather, they transformed into the kiwis.

Until recently, scientists recognized three species of kiwi that—the great spotted or roroa, the little spotted, and the brown, or tokoeka. They’re all much of a muchness; being nocturnal, they lack the bright colorful feathers that make most other birds