Bonobos are one of Earth’s most intelligent species, and seem much kinder than humans.
Do they now? Looking at the Wikipedia page you linked to...
De Waal has warned of the danger of romanticizing bonobos: “All animals are competitive by nature and cooperative only under specific circumstances” and that “when first writing about their behaviour, I spoke of ‘sex for peace’ precisely because bonobos had plenty of conflicts. There would obviously be no need for peacemaking if they lived in perfect harmony.” … bonobos kill monkeys for food. For the biologist, this fact is irrelevant in any discussion of aggression and peacefulness, because it is predation (due to hunger, not aggression) practiced against a different species. Hohmann and Surbeck published in 2008 that bonobos sometimes do hunt monkey species. Five incidents were observed in a group of bonobos in Salonga National Park, which seemed to reflect deliberate cooperative hunting. On three occasions, the hunt was successful, and infant monkeys were captured and eaten.
I’m not claiming that they’re some paragon of peace and cooperation, just that they seem substantially more peaceful and cooperative than humans do. E.g.
“There has never been a recorded case in captivity or in the wild of a bonobo killing another bonobo,” notes anthropologist Brian Hare.
Do they now? Looking at the Wikipedia page you linked to...
I’m not claiming that they’re some paragon of peace and cooperation, just that they seem substantially more peaceful and cooperative than humans do. E.g.
http://www.nsf.gov/news/special_reports/science_nation/bonobos.jsp
How many bonobos are there in captivity? How many non-bonobo chimps have killed other chimps?