After putting together a sort of mammal family tree, researchers have identified the common ancestor of all placental mammals—humans included. About the size of a rat, our insect-eating and tree-climbing ancestor first appeared on the scene shortly after an asteroid wiped out the dinosaurs  about 66 million years ago.
How would sequestration affect U.S. science? If you're confused—and who isn't?—by the seemingly endless debate between Congress and the White House over how to reduce the federal deficit, here are a few points to keep in mind.
Ant communication isn't all about pheromones. For decades, researchers have known that adults strum a special spike on their abdomens to call for help. But now it appears that the young ants are in on it, too. When their nest is threatened, immature ants can produce a less-complex version of the adult distress signal, while larvae and younger ants stay quiet.
Japan's whaling effort has cost taxpayers a total of $378 million since 1987 and produced very little valuable research, according to a new report. Commercial whaling has been banned since 1986, but countries are allowed to hunt whales for research purposes. Japan has been criticized for exploiting this loophole as a way to continue its commercial whaling endeavor.
Although strong swimmers in their "natural habitat," sperm don't do so well in a dish. But a new study suggests that common polystyrene Petri dishes may be partly to blame; their surfaces soften into a toxic sludge when they get wet, which may harm sperm cells. Diamond-coated quartz Petris don't suffer from the same problem, and it seems that a much higher percentage of swimmers can survive in their neutral environment. This is great news for in vitro fertilization, as the switch to diamond dishes could help fix the common problem of "poor sperm performance" and help boost success rates.
Richard III, one of England's most famous kings, has been found buried under a Leicester parking lot. Scientists confirmed the find by comparing DNA from the bones to two of the ruler's living relatives. The monarch died in battle in 1485, and his skeleton sports 10 wounds, including a large hole at the back of the skull where a halberdlike weapon sliced off part of his head.