Chimpanzees who share are chimpanzees who care, it seems.

Scientists from Germany, Switzerland and the United States have found that chimps who share their food have higher levels of the so-called love hormone oxytocin than those who don't.

Oxytocin is a hormone previously linked to bonding between mothers and their breastfeeding babies, both in primates and humans.

Researchers studying dozens of wild chimpanzees in Uganda found that they had higher levels of the hormone after sharing food than after mutual grooming — another important bonding behavior in primates.

Roman Wittig of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, said the effects were observed in both the giver and the receiver of food.

The study was published Wednesday in the journal Proceedings of the Royal Society B.