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The National Institutes of Health announced that by 2011 it will transfer almost two hundred chimpanzees from the Alamogordo Primate Facility in New Mexico to a lab in San Antonio, Texas, lab for use in invasive research. In 1995, the NIH announced a moratorium on the breeding of chimps in federally-supported labs, and as a result, scientists have developed alternative ways to investigate diseases. But there are still viruses, such as hepatitis C and HIV, that other species simply can't contract. This fact, some argue, makes it prudent to subject chimps to this sort of biomedical testing. Most of the chimps at Alamogordo are elderly, and all have already spent years as research subjects, many involving exposure to HIV or hepatitis C. Many of them are descendants of the chimps initially trained for space flight, as part of the Mercury program.

The scientific controversy has also become a political controversy: New Mexico Governor Bill Richardson and U.S. Senator Tom Udall (D-NM) among others, have voiced concern regarding the transfer. Richardson is pushing to convert the Alamogordo Facility into a chimp sanctuary, along the lines of the Chimp Haven facility in Louisiana. Alternatively, he suggests, Alamogordo could be used as a site for non-invasive behavioral research. Others, including Jane Goodall, have pointed out the negative political and fiscal implications of moving the chimps to San Antonio for biomedical research.

I appreciate the need for using animals in biomedical research. And I recognize that in the phylogenetic tree of life, drawing a line to distinguish the species that should not be involved in biomedical research from those that could be is mostly an arbitrary process. When each species is related to every other, who is to say which species get differential treatment and why?

An early argument from English biologist and palentologist Richard Owen (the very same Richard Owen who coined the term Dinosauria, meaning Terrible Reptile) was to classify species on the basis of brain anatomy. Owen announced that he had studied primate brains, and that the human brain had unique anatomical structures that were absent from other ape brains. Therefore, he reasoned, humans were a separate sub-class. Even then, in the late 1850s, there was severe disagreement. Darwin wrote, "I cannot swallow Man [being that] distinct from a Chimpanzee." And Thomas Huxley remarked in a lecture that, anatomically, gorillas are as similar to humans as they are to baboons. While the other great apes, and cetaceans, do have smaller prefrontal cortices than humans, the differences are ones of degree, and not of kind. The brain anatomy argument is of little use.

A second proposal is to distinguish species is the basis of overall brain size, if not in anatomical features. This argument can be quickly dismissed, however, as there are many animals with significantly larger brains than ours, such as elephants.

A third proposal has been made to distinguish humans from other animals on the basis of the proportion of a body occupied by a brain, since overall brain size is not useful. The human brain, for example, accounts for 2% of the human body. However, the brain of the tiny owl monkey (a monkey about the size of a pet cat) accounts for 3% of its body. This proposal is just as useless as the last one.

Some have proposed that encephalization quotient (EQ) should be used. Encephalization is the folding of the brain and increases volume and surface area, which has been shown to correlate with intelligence. Roughly, encephalization is the degree to which an the brain size of a given animal is larger than would be predicted given the size of its body. In this way, EQ takes allometry into account, so it should give us more mileage than any of the prior proposals.

Some of the proponents of a recent movement to give "human rights" to whales and dolphins cite that fact that dolphins are the second most encephalized beings on the planet, just after humans and just before the other great apes: chimpanzees, bonobos, gorillas, and orangutans.

The encephalization quotient seems a promising - if somewhat arbitrary - way of determining which species should be allowed to be involved in biomedical research. To put the question into perspective, an EQ of 1 suggests that relative brain size is exactly as expected. An EQ above 1 suggests that relative brain size is large, and an EQ less than 1 suggests a smaller brain than expected. Humans have an EQ of 7, great apes and some monkey species have EQs between 1.5 and 3, and several species of toothed cetaceans (the odontocetes) have EQs between 4 and 5.

What cognitive capacities are correlated with EQ? Species with high EQ (humans, great apes, odontocetes, and some monkey species) live in social groups with such complex organization that they can only be described as "political." In a 2002 paper, Lori Marino pointed out that these species engage in "cooperation, alliance formation, social maneuvering, manipulation and even deception." All of these cognitive skills are rarely seen outside of these species. In addition, primate and cetacean groups possess unique cultural "traditions." The transmission of information regarding tool use and manufacturing, for example, has been seen in chimpanzees, Japanese macaques, and bottlenose dolphins. Other social behaviors are also passed on via culture in all these species, such as methods of prey capture in orcas, and unique group-specific "dialects" in some whales and dolphins. Several bird species transmit social information culturally (such as in songbirds) and elephants also have possess aspects of culture. Several studies have shown that EQ is positively correlated with average clan size in primates and pod side cetaceans. Encephalization quotient, then, is a very good indicator of complex social abilities.

There is another important cognitive capacity that unites animals with high EQs: mirror self-recognition. Until relatively recently, it was thought to exist only in humans and great apes, though more recently, mirror self-recognition has been found in elephants, African grey parrots, dolphins, and (potentially) in Japanese macaques. Many believe that the mirror self-recognition test underlies a basic sense of self. Indeed, the great apes have shown varying levels of introspection, theory of mind, deception, and moral judgment - all abilities that require at least a rudimentary sense of self.

For me, the encephalization quotient gets the job done. While I approve of and encourage behavioral experiments with such species, I can't stand behind biomedical research on cetaceans, great apes, elephants, or any of the bird species whose cognitive capabilities mirror those of primates and cetaceans. As demonstrated by the mirror test and other experiments, chimpanzees possess a sense of self, and that alone is reason enough not to subject them to further biomedical research. In addition, the movement of the Alamogordo chimpanzees will disrupt their delicately balanced social groups, and will cause significant distress.

I recognize that the use of EQ to determine whether or not a particular species is suitable for biomedical research is at least partially arbitrary, but given its relationship with social cognition and the sense of self, it is a meaningful distinction for me. I further wish to emphasize that I am not suggesting that all biomedical research is unethical. On the contrary, I support most biomedical research; the medical benefits of animal research have been enormous. Clearly, the ethical questions of research with animals are hugely complicated, and I do not profess to have any answers. I know that the research that has been proposed for the Alamogordo chimps is important research, with medical implications, the results of which could save many human lives. The question we must address is if the relative benefits of research with a given species - such as chimpanzees - outweighs the risks to the lives of those animals. For me, with respect to chimpanzees, it doesn't. The governments of Europe made the same decision several years ago, disallowing any biomedical research on great apes. The US should follow suit.

I hope that the US government can put a hold on the transfer of the Alamogordo chimpanzees so that an alternative solution can be developed to meet the needs of the biomedical research community while respecting the complex lives and minds of these chimpanzees, who have already been subjected to so much research. The stated reason for the move of the chimpanzees is cost savings. Should the Alamogordo chimpanzees indeed be moved to San Antonio, I hope that the dollars saved be put into the further development of valid alternative research techniques, so that we can prevent the need for any future biomedical research with great apes.

Relevant links:

Jane Goodall's letter to NIH Director Francis Collins

Speaking of Research

Nature News

Convergence of complex cognitive abilities in cetaceans and primates

Whales, Dolphins, and Human Rights