evolution

Some sparrows sitting in a tree

Inbreeding detrimental for survival

Inbred birds don’t live as long and have fewer offspring than non-inbred birds. Inbreeding is equally harmful regardless of where the birds live.

Why the passenger pigeon died out

The passenger pigeon was once among the most numerous species on earth. The last passenger pigeon died in the Cinncinati Zoo just over 100 years ago. How did it all go so wrong?