extinction

The tubercled-blossom pearly mussel hasn't been seen since the late '60s. Once prolific in the Ohio River Basin, it has been officially declared extinct by the U.S. Fish and Wildlife Service.

A new book explores how overhunting and habitat destruction have left us with only a fraction of the foods that existed a century ago, and the changes that are needed to preserve our culinary variety.

"Protecting biodiversity amounts to protecting humanity," says UNESCO Director-General Audrey Azoulay, who warns that species are being lost at an alarming rate.

The International Union for the Conservation of Nature says the giraffe population has declined by as much as 40 percent in the past 30 years and could face extinction if the trend is not reversed.