A big new study says as the world gets warmer, people are more prone to get hot under the collar. Scientists found that aggressive acts like violent crimes and wars become more likely with each added degree.
The research analyzed 60 studies of such things as the historic collapses of empires, recent wars, violent crime rates in the United States and even cases where pitchers deliberately threw at batters. They found a common thread: Extreme weather - hot or dry - means more violence.
An author of the study, economist Solomon Hsiang of the University of California, Berkeley, said that when the weather gets bad people tend to be more willing to hurt others.
The study was published online Thursday by the journal Science.