04/11/2011
Chimps yawn more after watching familiar chimps yawn, showing a link between social status and empathy.
"Chimpanzees, like people, can 'catch' yawns from others. But not all yawns are created equal, it seems; chimps are more likely to catch yawns from a chimp they know than from a stranger, a new study found."
■Class discussion: Can you cause your classmate to yawn? Can you stop yourself from yawning once you start? Why is that?