The kiwi is the only living bird known to have nostrils at the end of its bill.
Most birds have nostrils near the base of the bill, but a kiwi’s nostrils sit near the tip. This placement helps it detect scents while probing leaf litter and soil for earthworms, insects and other invertebrates. Sensitive bristles around the bill also help the bird investigate its surroundings.
Kiwis are flightless birds native to New Zealand. They are nocturnal, have unusually dense feathers that resemble hair, and possess strong legs suited to running and digging. Their reduced wings are hidden beneath the plumage, and their small tail is absent.
The kiwi’s egg is extraordinarily large relative to the female’s body. Although kiwis are birds, their biology shows several unusual features associated with their isolated island evolution. They are not closely related to mammals despite their hair-like feathers.