A large flightless pigeon that lived on the island of Mauritius in the Indian Ocean, the dodo had few natural enemies.
But in the 1500s, European sailors arrived and found that the dodo was easy to hunt. By about 1680, all the dodos had been killed.
Worldwide, roughly 150 bird species have become extinct since then. Some died out naturally, but most have become extinct due to humans. Global warming is the newest problem. Some scientists predict that drought conditions brought on by global warming could dry up nearly all the prairie wetlands, where many ducks nest.
