Krefeld Zoo in Germany said chimpanzees, orangutans, gorillas, fruit bats and birds were among the estimated 30 animals killed.
A study shows that honeybees can learn to match symbols and numerosities, much like we humans do.
Scientists also observed the chimps sharing the tortoise meat between individuals.
Using tools to dig for food underground was once thought to be a behavior unique to humans.
The results could have important implications for understanding when humans and other great apes diverged in evolutionary terms.
"It's likely that all great apes can understand at least some of this system of gestures."
Chimps beat us to the friendship game.