The opinion of scientists is divided about the relation between mass extinctions and impact craters caused by asteroid and comet showers on Earth. Now two researchers, Michael Rampino, a New York University geologist, and Ken Caldeira, a scientist in the Carnegie Institution's Department of Global Ecology, have concluded through their observations that the age of impact craters is linked to mass extinctions of life on Earth, including the demise of the dinosaurs. They have observed a cyclical pattern in which impacts and extinction events have taken place every 26 million years. To support their theory, the two scientists performed time-series analyses of impacts and extinctions and came to the conclusion that the correlation between the formation of the impacts and extinction events over the past 260 million years suggests a striking cause-and-effect relationship.
Read more in Science Daily.