The importance of the domestication of horses to human civilisations is undisputed. But there are conflicting hypotheses about the origins of tamed horses; the 'restricted origin' hypothesis postulates selective breeding of a few founding lineages followed by distribution, while the 'multiple origins hypothesis' suggests independent recruitment of a large number of founders over an extended time period and geographical location. In the January 19
Thousands of people around the world gathered to show support for science today. Here’s a sampling of sights and signs from the Marches for Science in Berlin, Chicago, and Washington, DC.