Why Is the Kiwi's Egg So Big?
3 days ago
- #kiwi
- #birds
- #evolution
- The kiwi is a flightless, nocturnal bird with fur-like feathers and nostrils at the tip of its beak.
- Kiwis lay eggs that can weigh up to a quarter of their body mass, the largest proportionally of any bird.
- Previous theories suggested the kiwi's large egg was a holdover from larger ancestors, like the moa.
- New DNA research shows the kiwi's closest relative is the tinamou, not the moa, debunking the big-bird-big-egg theory.
- The kiwi likely evolved its large egg as an adaptation, providing chicks with enough yolk to survive without immediate feeding.
- This adaptation may help kiwi chicks evade predators by being more precocious at birth.