Volcanic activity did not play a direct role in the mass extinction event that killed the dinosaurs, according to an international team of researchers. It was all about the asteroid.
Populations of mammals, birds, fish, reptiles, and amphibians have, on average, declined in size by 60 percent in just over 40 years.
A series of reports compiled by nearly 600 scientists meeting in Columbia paint a grim picture of the world at the end of the century, with human activities driving the sixth mass extinction in Earth’s history.
