Clay Revelation: 5 Most Incredible Discoveries of the Week

A revision for the history books when it comes to China and a surprise find about spiders were among the intriguing discoveries of the week:

• China's Terracotta Army May Rewrite History: Archaeologists studying a famous trove of terracotta figures dug up in China think they reveal that the Chinese were in contact with the West much earlier than thought, about 1,500 years before the arrival of Marco Polo. The insight comes not just from the discovery of DNA at ancient gravesites but from the style of those lifesize clay figures.
• Spiders Can Hear You 'Walking and Talking': If you're already scared of spiders, you're not going to like this next part. A new study found that spiders—specifically a species of jumping spider—can hear sounds from further than 10 feet away. Previously, scientists believed spiders could only sense vibrations in the air from a few centimeters away, but now it seems they can hear you "walking and talking," says one researcher.
• Athletes Shouldn't Feel Guilty About Sex Before the Game: It's conventional wisdom in sports: For peak performance, athletes should abstain from sex just before game day. Italian researchers looked into the subject, however, and found that it's not supported by substantive research. Marathon runners, in particular, will be very interested in their findings.

• Don't Work Out While Angry: Exercising to "blow off steam" when you're furious is how a lot of people end up having their first heart attack, new research warns. It has to do with the similar effects that anger and exercise have on the body, and the potent result when they're combined.
• Bumblebees Learn Trick, Surprise Researchers: Scientists found that bumblebees could be trained to pull a string in order to get a sip of sweetened water. Actually, they were able to train just a rare few to do this—but when other bees watched the trained bees do it, most picked up on it quickly. And that might tell us something about how cultural traits get passed along.

Click to read about more discoveries, including the revelation that our universe has far more galaxies than thought. (More discoveries stories.)