by by Emma Berry

illustration by by Peter Scheidt

Travis was 14 and, by all accounts, an all-American guy. He loved baseball and steak. He'd appeared in a commercial for Old Navy cargo shorts. He even dressed himself and drank out of stemware--no small feat, given that Travis was a chimpanzee. He belonged to Sandra Herold, a Connecticut woman who had raised him since infancy and considered him a son. Travis ate at the dinner table with Herold, accompanied her on errands and even helped her care for her horses.

And like most 14-year-olds, Travis could get angry. But when male chimpanzees--up to five times as strong as human males--get angry, they're hard to stop. On February 16, 2009, Travis attacked Herold's friend Charla Nash. Travis had met Nash, a single mom who worked for Herold's towing company, many times before the incident. It's still uncertain why he attacked when he did. But by the time police arrived, Travis had ripped Nash's face off.
When news of the attack surfaced, pundits rushed to criticize Herold for treating a wild animal as an adopted child. But is it so surprising that we think of chimps as little furry people? After all, our genes are about 98 percent identical. Chimpanzees and their cousins, bonobos, who share the genus Pan, are our closest living primate relatives. And over the past century, research has blurred the lines separating us.
Jane Goodall's long-term observations of chimpanzees in Tanzania's Gombe Stream National Park, which began in 1960 and are continued by a team of researchers to this day, signaled a shift in the way humans once thought about the animals. Goodall became emotionally involved with her subjects, giving them names and describing their personalities. Along the way, she offered the first evidence that chimpanzees form complex family structures, make their own tools and even engage in warfare, activities that had once been considered uniquely human. When he heard about the chimps' tool-making skills, the anthropologist Louis Leakey remarked, "Now we must redefine tool, redefine Man or accept chimpanzees as humans." Goodall's observations raised serious ethical and philosophical questions--if chimps are so much like us, what are our responsibilities to them? And what does our response to them say about us?
While chimpanzees can't articulate human speech sounds, they can use their hands to produce signs. In 1966, researchers Allen and Beatrix Gardner raised a young chimpanzee named Washoe like a deaf human child, playing games with her, cuddling her and signing to her constantly. The Gardners called Washoe the first non-human to acquire American Sign Language. When she died in 2007, she was reported to have a vocabulary of around 250 signs.
Researchers studying chimpanzees in the wild and in captivity have detailed evidence that chimpanzees perform certain cognitive functions much like humans do. In March, Swedish researcher Mathias Osvath published a case study of a zoo chimpanzee who would calmly collect stones and pieces of concrete to use later as missiles when angered. This act "implies advanced consciousness and cognition traditionally not associated with nonhuman animals," he wrote. But after ten years observing the chimpanzee, he argues that the evidence is unambiguous: planning for a future emotional state isn't a uniquely human trait after all.
Researchers have also suggested that chimpanzees demonstrate true forms of altruism, ones that can't be fully explained by self-interest or kin selection. For example, a 2007 study by Felix Warneken and colleagues showed they "helped an unfamiliar human to the same degree as did human infants, irrespective of being rewarded [...] or whether the helping was costly." Chimps can also perform novel tasks to help others. Some even argue that they mourn.
The studies have led some to push for legal rights for chimpanzees. In 1993, Paola Cavalieri and Princeton philosopher Peter Singer started The Great Apes Project, which calls for an international declaration of rights for "near-human" primates--chimpanzees, bonobos, gorillas and orangutangs--in part by drawing parallels between nonhuman primates and human children. In 2008, the Spanish Parliament gave the Project its first major victory, declaring that great apes have the right to life, liberty and freedom from torture. And in 2007, a group of Austrians sued on behalf of a chimpanzee named Hiasl, arguing that he should be granted legal personhood so that a guardian could be appointed for him.
About 700 chimpanzees are kept as pets or work in the entertainment industry in the US. Another 700 live in zoos or animal sanctuaries. The rest (around 1200, according to the animal rights group Humane Society of the United States) are used in behavioral and medical research. Since the early 20th century, researchers have taken advantage of their cognitive and immunological similarity to humans to study subjects as diverse as polio, addiction, brain damage and the effects of space flight. Today, chimpanzees are mostly used in behavioral research and as models of viral infections like hepatitis and malaria. "There are diseases that can only be studied in chimpanzees," Alice Ra'anan, director of science policy at the American Physiological Society, told Science magazine in March.
Then again, chimps may not be as like us as we think. The earliest and most salient criticism of Goodall's work--that when she became attached to the Gombe chimpanzees, she was unable to observe them objectively--has been repeated as a criticism of other assertions of the "humanity" of chimpanzees. Attempts to repeat the Washoe experiment in a controlled setting have failed. Cognitive scientist David Premack, noting that chimps do not develop the complex syntax that characterizes human language, argues that chimp "language" is merely gesture or symbol.
Despite its relative complexity, the chimpanzee brain is still only one-third the size of a human brain. And while chimps serve as good models for other infectious diseases, researchers' attempts to use them to study HIV/AIDS have failed. They found that, while chimpanzees are the only animals that can contract human HIV, they are much more resistant to the virus than are humans, and they almost never develop AIDS. Researchers now use other primates infected with Simian Immunodeficiency Virus, a cousin of HIV, to study the disease.
Other than Gabon, the United States is now the only country that uses chimpanzees for medical research--and that could be changing. Animal rights groups have called for an immediate end to the use of primates in invasive research. The NIH has expedited its program to find alternatives to primate testing. Having determined that it would be unethical to euthanize them, the NIH sends chimpanzees that can no longer be used in medical research to federally-funded sanctuaries, where chimps lounge in hammocks, drink banana smoothies and even watch television. In October, the pharmaceutical company GlaxoSmithKline voluntary ended its testing on all "great apes," including chimpanzees.
None of this will make a difference for Travis; police officers shot him to death on the scene. And even if they hadn't, it's hard to say what he would think about being considered a child, a person or a wild animal--if he could think about it at all. We can only guess what goes on in a chimp's brain, but it's not a stretch to say that they're probably not concerned with philosophical concepts like personhood, legal rights and what constitutes language.
But then again, couldn't we say the same about children?

Emma Berry B'11 hopes your chimpanzee doesn't cry throughout the entire flight.