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Susan Larson spends some time with Hercules in her Stony Brook lab.

Susan Larson spends some time with Hercules in her Stony Brook lab.


The scientist behind the 'personhood' chimps

In 2013, the Nonhuman Rights Project filed a series of lawsuits asking courts to recognize four New York chimpanzees as legal persons and free them from captivity. The animal rights group, which hopes to set a precedent for research chimps everywhere, has yet to succeed, but in April a judge ordered Stony Brook University to defend its possession of two of these animals, Hercules and Leo. Last month, the group and the university squared off in court, and the judge is expected to issue a decision soon. But the scientist working with the chimps, anatomist Susan Larson, has remained largely silent until now. In an exclusive interview, Larson talks about her work with these animals and the impact the litigation is having on her studies—and research animals in general. This interview has been edited for clarity and brevity.

Q: Where did Hercules and Leo come from?

A: They were born 8 years ago at the New Iberia Research Center in Louisiana. They were among the last juveniles New Iberia had. We've had them on loan for 6 years.

Q: What kind of work do you do with them?

A: We're interested in learning about the evolution of bipedalism by actually looking at what real animals do. Over the past 30 years, we've looked at 17 different species of primates, including 11 chimpanzees. Chimpanzees are the best model because they are so close to us. When we compare how they walk to how we walk, we can feed those data into computer models that may help us understand how early hominids like Lucy moved around. The work we're doing with Hercules and Leo is the most important work we've done.

Q: What do the experiments involve?

A: We do three types of experiments: motion analysis, which involves painting nontoxic white markers on the chimpanzees' limbs so video cameras can accurately track their movements; kinetic analysis, where we look at the forces generated by the animals as they walk over force plates; and electro myography, where fine-wire electrodes inserted into the muscles tell us how they contribute to the motion we're studying. We don't do anything with these chimpanzees that we haven't done on ourselves.

Q: Why can't you do this kind of work in a zoo or sanctuary?

A: The work we do requires a lot of time and effort. You need to be able to collect many samples of the same behavior. Animals in zoos and sanctuaries are notoriously unwilling to do what we want them to. Hercules and Leo do everything for a grape or a cherry or a bit of juice.

Q: What are their living conditions?

A: We have a very large facility. It's the equivalent of three moderate-sized bedrooms that are adjacent to each other. They have hammocks, ropes for climbing, and magazines to tear up. We have an animal handler whose job is to keep them comfortable and stimulated. She hides treats in cardboard boxes and gives them plastic toys like airplanes to play with. We try to make their day-to-day lives as interesting as possible. We don't want them to feel threatened or frightened; otherwise we wouldn't get reliable results.

Q: How do you view your relationship with them?

A: I interact with them weekly, but the animal handler has the most direct contact with them. I don't have the bond with them that the animal handler does; she loves them and loves spending time with them. I see them as collaborators, as willing participants in the project. And I respect them. I would never ask them to ride a bicycle or anything goofy like that.

Q: How have perceptions of animal research changed in the decades you have been working with primates?

A: There has been a sea change in attitudes towards chimpanzee research. Oversight has become much stricter, and getting approval to do this work has been harder. The space we have used to be considered vast for these animals; now it's considered average.

In the past, this research wasn't considered controversial; my colleagues used to appear on television programs to talk about their work. Now, my university is very reticent to talk about this research at all. I've been consistently advised never to respond to reporters, even though I don't think there's anything that needs to be concealed. I'm very proud of the work we do, and I feel comfortable with the procedures we use. They worry about us being targeted by animal rights activists, so they think it's better to say nothing than to say something that could be used against you.

Q: What do you make of the movement to turn chimpanzees into legal persons?

A: I think giving them personhood status is a sham. If anyone treats them like people, it's us. We don't treat them like prisoners; we only work with them when they're willing. But we have to be cognizant that these are chimpanzees—not people. They can't provide for themselves; they need human care and protection. They are remarkable animals, and we should respect what they are and what they need. You don't have to pretend something is a person to treat it justly.

Q: How has the litigation affected you?

A: Stony Brook is keeping me out of it. It hasn't changed our protocols, but the university has scrutinized us much more closely. They're not happy about it. I find a lot of what the other side is saying very untrue and hurtful. It's upsetting when someone calls you an evil scientist, or when they say we're causing pain or needless suffering. It's strange to hear people talking about these animals when they don't know who they are.

Q: What's next for Hercules and Leo?

A: Our project is winding up in the next few weeks. After that, it's New Iberia's decision what to do with them. They've said they intend to retire them to a sanctuary. After that, our facility will go dormant.

Q: What do you see as the future of chimp research?

A: The U.S. Fish and Wildlife Service is considering classifying both captive and wild chimpanzees as endangered. NIH [the National Institutes of Health] is saying they're not as useful as animal models. Grant money is very hard to come by, and it's becoming increasingly difficult to meet the regulatory standards. Pretty soon, the kind of work I do will not be possible anymore. We're going to end up with chimpanzees completely cut off from humans; they'll become alien beings. And that makes me sad, because I think there are still a lot of things we can learn from them.