Humanity's main impact on the extinction rate is landscape modification, an impact greatly increased by the burgeoning human population. Now standing at 5.7 billion and growing at a rate of 1.6 ...

Scientists estimate that a third or more of all the roughly 6,300 known species of amphibians are at risk of extinction [6]. Frogs, toads, and salamanders are disappearing because of habitat loss, ...

According to scientists who maintain that dinosaur extinction came quickly, the impact must have spelled the cataclysmic end. For months, scientists conclude, dense clouds of dust blocked the sun ...