In the animal world, there is an overwhelming tendency for these West Side Story lyrics to ring true: “One of your Own Kind/Stick to your own kind!” However, primates in captivity will readily associate with members of different primate species, human caretakers, and even other types of animals entirely. Koko the gorilla proved the tenderness of the primate spirit with her acceptance and motherly treatment of the kitten “All Ball,” and monkeys have also been seen attempting to raise kittens as their own babies. Why share food with a member of another species? It’s a type of tit for tat strategy, meaning that the primate that does the sharing benefits in some way from the partnership. Maybe making an unusual friend will offer you protection, social company, or food at a later date, and thus the costs of losing a little food are outweighed by the potential benefit of a long-term relationship. Human primates have taken this strategy to the ultimate level, domesticating animals that have been associating with us for thousands of years, as is the case with dogs. Presumably, wild dogs offered our ancestors protection from predators by standing guard near human camps and warning of intruders. In return, the dogs were allowed to feed on scraps that humans tossed to them from their camp. Known as a mutualism, a situation gradually evolved in which both humans and dogs received benefit from the arrangement,which eventually led to the domestication of hundreds of dog species.Dogs didn’t have to work as hard for food, and humans were able to train dogs to work for them. Watch below as an orangutan and dog form an unlikely but heartwarming partnership.

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My seventh trip to the field, but I still can’t get enough of seeing wild monkeys in action! I am currently in Panama serving as a darter’s assistant, whereby we are helping researchers tranquilize monkeys for their ppps (particular primate projects!) This time, we are collaring individuals with GPS collars that give the researchers continuous data on when the animals are active, where they are traveling, and even whether they are spending more time suspended upside down or right side up. While the animals are tranquilized, we also collect other important information, such as body measurements, whether any parasites such as ticks or worms are present, and a few blood and fecal samples. Researchers can use this information to determine the health status of their subjects and to perform genetic analyses to figure out the family tree of their research groups.

The actual darting is done by my good friend, who I have been working with for 10 years and who has almost 20 years of experience shooting all sorts of primates with little neon darts loaded with sleepy-time drugs. Once the dartman hits a primate, I help follow the animal as the effects of the drugs kick in, which takes about 2 minutes total. Prepped with a large cargo net, my job is to catch the primate once it falls from the trees, often very high above our heads so that it is not injured from the rapid descent. Once the animal falls, we have to do all the processing quickly, since they begin to wake up within an hour. After about two hours, the special primates are tagged and ready to be released back up into the same spot where we caught them, usually a bit disoriented, but quickly recovering and leaving to rejoin their groups.

This trip, we are focusing on capturing spider monkeys and capuchins. Spider monkeys are wonderful darting subjects since they tend to stay still for long periods of time and hang upside down, derriers pointing downward, presenting the perfect target for a loaded dart. Capuchins, on the other hand, are one of the most difficult primates to dart. They are small and very rarely stop moving long enough to get a good shot. In addition, they are extremely smart, and they recognize our darter from previous experiences with him. As soon as he shows up, they high tail it into the opposite direction! But, what would true fieldwork be without a few um…challenges? The trails on BCI are difficult, since they are steep, but the facilities here are marvelous. We actually have hot showers and ice cold drinks at the end of our long day, which is definitely as good as it gets in this line of work!