Though the common ancestor of all modern birds could fly, many different bird species have independently lost their flight. Flight can have incredible benefits, especially for escaping predators, hunting and traveling long distances. But it also has high costs: consuming huge amounts of energy and limiting body size and weight. Gillian Gibb explores what makes birds give up the power of flight. [TED-Ed Animation by Anton Bogaty].

Gillian Gibb: Why can't some birds fly?

Why can't some birds fly?

Flightless birds, from cassowaries to kiwis, adapt and thrive globally without flight, showcasing nature's mastery of survival.

Adapting to life without flight, birds like the Takahe exhibit remarkable evolutionary shifts, optimizing energy and survival.

Despite the advantages of flightlessness, introduced predators pose significant threats, underscoring fragile ecological balances.