19 December 2005

Penguins and Flight


Matt in Phoenix also asked why penguins cannot fly. This is an interesting question because penguins evolved from birds that did once fly. However, through time, penguin ancestors found it more useful to swim from predators than fly away from them, and flight became a vestigial trait. This is true with many now-flightless birds, including the ostrich, emu and kiwi (pictured).

1 comment:

James (Silver Spring, MD) said...

Question: The universe is everything. And the universe is expanding. What is the universe expanding into if the universe is everything?