"and other activities were responsible for pushing populations of animals to extinction long before the , which began about ten thousand years ago. Today, however, our collective assault on animals, plants, and s has reached such a horrendous level that any alarm we might sound will be too faint to match the tragedy that is unfolding. ... In the past century or so, both the and of Homo sapiens have increased spectacularly, and this is this is the root cause of the rapid acceleration in human-caused species extinctions, precipitating what is now called the ."