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Published: Sunday, 6/15/2003

All in the family

BY JENNI LAIDMAN
BLADE SCIENCE WRITER

DETROIT - He rarely e-mails. He doesn't know how to type.

His office at the Wayne State University School of Medicine is barely as wide as the hallway that leads to it, and not nearly wide enough to walk through it without tripping over chairs.

And he looks, for all the world, like a man who might keep butterscotch candies in his pocket in case of visiting grandchildren.

Yet Morris Goodman is a rebel. His life's work has changed how we think about ourselves, and our place in the natural world. And now, at 78, he's pushing for greater, more controversial transformations.

This isn't simply the stuff of subtle, intellectual, scientist-only debate. He takes stands any zoo visitor can chew on. He dropped his latest bomb recently when he said the exclusive club of Homo sapiens needs to open the doors to new members. Slide over, folks, because here come the chimpanzees. Dr. Goodman says they belong in the genus Homo. We can keep the sapien part - the species tag - to ourselves.

That scientists aren't lining up to applaud this latest innovation in the human genealogy isn't anything new to Dr. Goodman. Forty years ago, he roused the silverbacks of anthropology when he proposed putting apes in the human family. Today, many researchers agree with Dr. Goodman's once-astonishing conclusion: We are family. The question these days is whether we can keep a branch to ourselves much longer.

Dr. Goodman has been sawing off the limbs we thought we had all to ourselves ever since a 1962 meeting when the researchers he admired - including the late George Gaylord Simpson - beat their chests against his initial proposal.

For all the debate he has stirred, and the controversy he continues to create, Dr. Goodman sounds nothing like the revolutionary he is. Nor does he get a rebel's welcome. With few exceptions, his colleagues regard him with enormous affection.

Jeffrey Rogers, a scientist at the Southwest Biomedical Research Foundation in Texas, is fairly typical: “It's hard to think of someone who's had a more consistent and positive impact. With almost a quiet, unassuming personality he's done effective, productive, groundbreaking science with humility and gentleness.”

Hardly the description of an iconoclast.

Even today, Dr. Goodman sounds a tad dismayed by the reception to his maiden proposition on human-ape relations 40 years ago.

“I thought I was in agreement with Simpson's own views, as well as Darwin's. That's why I was a little surprised when they didn't like it.” He laughs, sounding a shade like Ed Wynn.

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The notion of human and apes in the same family seems less-than revolutionary today. So it's hard to realize what a departure it was in the 1960s. Most of us recognize that our genes and chimpanzee genes are nearly identical. An army of researchers, from Jane Goodall to Frans de Waal, to Sally Boysen at Ohio State University, have established that apes ape us behaviorally as well: They show complex emotions, share friendship and reconciliation behaviors, use tools, learn symbolic language, and show some hallmarks of culture.

When he introduced his family plan, Dr. Goodman wasn't talking to a room full of creationists, whose religious objections would negate any scientific evidence he mustered. He was addressing people who considered evolution the active and organizing ingredient in biology.

But the fact was, even though Charles Darwin speculated on our kinship with apes in 1871, for the next 100 years, scientists continued to see a profound gap in our shared histories.

“When I went to grad school in the '60s, the generally accepted view of things was that ... there was a very deep chasm separating us from our closest relatives,” said Mark Weiss, program director for physical anthropology at the National Science Foundation. Dr. Weiss did his doctoral work in Dr. Goodman's laboratory.

The gulf between humans and apes was 15 million to 20 million years long, researchers then thought. Gorillas and chimps were close relations, and humans were, at best, a distant evolutionary outpost of both, and maybe a tad embarrassed by the kinship.

Now, that view has been overturned. Chimps and humans split 6 million years ago. Chimps and humans are closer relations than chimps and gorillas, and there's an active campaign to grant rights to great apes, remove them from medical research facilities, and keep them out of zoos.

Dr. Goodman, using antibodies to probe similarities between species, helped reshape this history.

Initially, “I didn't question the conventional separation of humans from the rest of the apes,” he said. Then came his antibody work.

Antibodies are very particular proteins, each specially designed by our bodies to interact with specific molecules. This choosiness allowed Dr. Goodman to work out a mix-and-match puzzle among the primates.

As evidence accumulated, he saw that chimps and gorillas were almost identical to humans. To him, the similarities demanded a change in the way living things are classified.

At the time, his conclusion was shattering.

Dr. Goodman's ideas “were so far ahead of his time it's ridiculous,” said Richard Potts, director of the human origins program at the Smithsonian Institution.

While many researchers embraced Dr. Goodman's evidence that gorillas, chimps, and humans shared a common ancestry, most felt no adoption into the family was in order. Man was simply the “offspring of a markedly divergent lineage.”

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Anthropology's chilly reception to Dr. Goodman's early ideas didn't cool his ardor for reclassifying apes. In 1971, using more advanced molecular techniques, he offered evidence that humans, chimps, and gorillas were closer yet, proposing that the two hairy apes join the human subfamily.

In 1989, now conducting detailed genetic analyses, he moved chimpanzees a few more baby steps toward humanity, plopping them into the same subtribe as humans.

In 1996, he wrote that one might make a case for putting humans and chimps in the same genus, but stopped short of actually making the proposal.

Dr. Goodman bases his argument for the cuddling of humans and chimps with complex discussions about how we organize life.

But the bottom line of all those arguments is that at every step, molecules should be the premier consideration. Only genes provide “an objective yardstick'' by which to analyze our similarities and differences, Dr. Goodman says. To do otherwise, he says, is to act on “metaphysical constructs” that assume humanity is the measure of all things. By arbitrarily deciding which property of Homo sapien sets us apart from other apes - be it language or the ability to walk upright - we demonstrate a human-centered bias that has nothing to do with science, Dr. Goodman argues.

It's not to say there are no differences between humans and chimps, Dr. Goodman says.

“Genetically, dogs are very similar and nobody questions that they're members of the same species. Yet if you look at their general appearance, the differences are as pronounced - if not more pronounced - than the appearance of chimps compared to that of humans.''

In the most recent paper to come out of Dr. Goodman's lab, published in the Proceedings of the National Academy of Science, lead author Derek Wildman analyzed the very building blocks of 97 genes - some 90,000 nucleotides. He compared genetic changes that occurred in humans, chimpanzees, gorillas, orangutans, and, to a lesser extent, mice. The team then determined which changes altered a protein and which didn't.

The analysis revealed that humans and chimps were 98.4 percent identical when only meaningless changes were compared. But, when it came to changes that altered proteins - and therefore some cellular function - human and chimpanzee genes were even closer: 99.4 percent identical.

Little more than 1 percent of our DNA codes for proteins. Although noncoding DNA has always showed a close relationship between humans and chimps, many argued that any careful examination of the coding regions would reveal the wide gap between chimpanzees and humans. Instead, this study suggests an even clearer fraternity in coding regions.

While few are arguing with this genetic analysis, the conclusion Drs. Goodman and Wildman draw from the data are another thing entirely. Few in the field of primate evolution agree that this means humans and chimpanzees belong in the genus Homo.

Perhaps Dr. Goodman's most vehement opponent is Jon Marks, a molecular anthropologist from the University of North Carolina at Charlotte.

In an e-mail message, Dr. Marks dismisses Dr. Goodman's recent finding as “the same old paper with the same old tunnel vision. Just because (Dr. Goodman) cannot tell humans from chimps by looking at their genes, he denies that anyone can from looking at anything.”

Dr. Marks, author of the 2002 book, What it Means to be 98 Percent Chimpanzee may be the extreme view here.

But even Dr. Potts of the Smithsonian thinks Dr. Goodman's latest paper is “going a little too far.”

“While, from a molecular side that may work out very well, there is none-the-less - when you step back and take a lot at the evolutionary picture - it's clear all fossil humans are bipeds (walk on two legs) with small canine teeth - all things that mean human, not chimpanzee.”

Dr. Potts also points out that human and chimp DNA is packaged differently. Human DNA winds into onto 23 pairs of chromosomes. Chimp DNA makes 24 pairs.

Still, even when they disagree with him, most researchers call the Detroit researcher a groundbreaker in their field.

“He was really the person who was on the leading edge of applying molecular genetic techniques to find the place of humans in the natural world,'' said Dr. Potts of the Smithsonian. “It's extraordinarily cutting edge.”

“Oh my goodness! He is an icon,” says Anne Yoder, an evolutionary biologist at Yale University. “He pretty much single-handedly started the field of molecular primatology and molecular primate genetics. He's just fabulous. He's definitely one of my heroes.”

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While Dr. Goodman argues that genes are the objective measure, there is no escaping the political, ethical, and philosophical impact of his classification schemes. If chimps are as closely related to us as our ancestors Homo erectus and Homo habilis, that may change a few things. Would we justify, for instance, putting Homo erectus in a zoo if he were alive today? So, it's no great surprise that some of the champions of Dr. Goodman's latest proposal are those concerned with ape welfare.

Steven Wise is a Harvard Law professor who specializes in the legal rights of animals, a theory he explored in his 2001 book, Rattling the Cage.

Putting chimps in the genus Homo “certainly makes the argument for legal personhood for chimpanzees more powerful,'' Dr. Wise said.

Dr. Wise sees the evidence for the classification of Homo for chimps as inarguable: “Anyone from Mars looking at the genetics of humans and chimpanzees wouldn't be able to tell them apart.”

He dismisses arguments that differences in behavior, appearance, and cognition would overwhelm such a reclassification.

“When I look at other species, I see hardly anyone talking about behavior. They're usually talking about genetic differences. Only when we talk about humans do we start talking about behavioral differences. There are different sorts of rules when humans are involved.''

Sally Boysen studies chimpanzee behavior at Ohio State University. Her research focuses on chimpanzee intelligence. She agrees chimps belong in the human genus.

“Science should lead the way for this kind of re-evaluation. As we get more sophisticated technologies, and we get more information, we need to pay attention to it.”

“There's a wealth of information, three to four decades of research into chimpanzee cognition,'' Dr. Boysen says. “It's time for a serious reappraisal.”



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