Unlike most nocturnal birds, they have very small eyes, and they also don’t have a lot of brain space devoted to their visual system. Their eyes are certainly still useful at night, but aren’t the most important source of information. (In fact, at least a few rowi are known to have survived just fine in the wild despite being completely blind!) Instead, kiwi make great use of their sense of smell and their sense of touch. They have long modified feathers around their faces – like mammal whiskers, which help them feel their way around. Their long beaks have two nifty tools that help them find invertebrates hiding the soil: their bill tips are sensitive to touch and vibrations, and their nostrils are also at the bill tips rather than up near their heads. If you think about it, eyes aren’t much use when you’re trying to find food that’s underground! They also have great hearing, which probably helps them listen out for food scuttling around above ground, as well as listening out for each other.

Bonus skill: kiwi probably have terrific mental maps of their territories. They’re long-lived, and tend to stay in more or less the same place once they’ve settled down on a territory, so they’ll know their own patch *really* well.

Roroa and pūkeko don’t really have much opportunity to come into conflict, because they prefer different sorts of habitats. Roroa tend to live in forests, and will also use different habitats right next to forests like native shrublands,and tussock lands. Pūkeko, on the other hand, are wetland birds and like to hang out near calm, swampy areas. They also like pastures and other grassy areas. Even if roroa and pūkeko did find themselves living in the same spot, they probably wouldn’t be fighting over food: roroa eat mostly invertebrates, and pūkeko eat mostly plants.

The ancient ancestors of kiwi flew to New Zealand sometime between 50-65 million years ago. Their nearest relatives on the avian family tree are Madagascar’s extinct elephant birds, not – as we used to think – the moa. The ancestors of moa flew here as well, but their nearest relatives are the still-living (and still-flying) tinamous of South America. We can’t say exactly how long it took for pre-kiwi to stop flying and become kiwi. But we do think that pre-moa got here before pre-kiwi. This might be why kiwi stayed relatively small: moa had a head start on evolving big, flightless bodies, so the kiwi stayed small and took to running around at night instead.

Fun fact from Laura: when I say “we used to think” I’m not talking about last century. The DNA work that clarified these relationships only came out in the last decade. Before that, the thought was that the ancestors of kiwi and moa were already on future-NZ when it separated from Australia around 80 million years ago, and that they were already flightless. That’s what I used to teach at Lincoln. Science changes, scientists re-write lectures