HUMANITY: THREATENED is a chronicle of danger and extinction. This guide explains which animals will probably disappear from our planet next and why it may be too late for others. Based on the International Union for the Conservation of Nature’s Red List, our top 100 threatened species include common favorites, such as gorillas, tigers, polar bears, and whales. They also include some lesser known but equally astonishing species, such as saolas, gharials, and flying squirrels. THREATENED is above all an important wake-up call: These species are essential to our ecosystem, and once they disappear from the face of the Earth, there is no going back--Cover.