Chimpanzees learn hand-holding from influential apes

Holding hands isn’t just for human sweethearts. Chimps often clutch each other’s palms while grooming in a behavior known as handclasping. Handclasping is common among chimpanzees, and this endearing act is a social custom passed on through generations, as a study published today in Science Advances reports. What’s more, a chimp will mimic the handclasp style of the most influential members of the group, the primatologists discovered. 

“This study is fascinating because it captures the nuance of social transmission of customs among chimpanzees,” says Mary Lee Jensvold,…