Questions about the world’s oldest bird fossil

A paleontologist going after the earliest bird may have ended up with a mouthful of worms.

By Carl Zimmer|Friday, May 01, 1992
RELATED TAGS: ENDANGERED SPECIES
If you believe what you read in the papers, Sankar Chatterjee ought to be the crown prince of paleontology. Six years ago he announced that he had found the world’s oldest bird fossil. It beat the previous record not by a mere 1 or 2 million years but by 75 million. With one quick kick, it seemed, Chatterjee sent paleontologists who thought they knew something about how birds had evolved tumbling in the dust.

Discovering the oldest fossil of anything is obviously wonderful for a paleontologist’s career. The fossil instantly becomes the centerpiece of any future theory about how an animal evolved and what it evolved from. And not incidentally, the fossil finder becomes just as important. In 1974, for example, paleoanthropologist Donald Johanson found Lucy, the oldest, most complete fossil of an upright human ancestor. The discovery gave him so much clout that he could later found and head his own research organization, the Institute of Human Origins, in Berkeley.

Chatterjee, however, is not the head of any institute of avian origins. He still lives in Lubbock, and he still teaches at Texas Tech University, where he’s been for 12 years. Instead of reaping the benefits of a major discovery, he’s at the center of a storm of controversy. A number of critics consider his bones to be a hopeless mess of fragments that doesn’t even come close to supporting his claim to the oldest bird. These critics also attack Chatterjee’s professional conduct; only in the past year has he begun to publish his results, and only in piecemeal form, at that. Considering all the attention he garnered in 1986, it perplexes people that Chatterjee took so long. His more vocal critics say his work is misleading and incapable of supporting his headlines. In a few years, claims Tim Rowe of the University of Texas, this thing will be pointed at and laughed at.

The soft-spoken, congenial 48-year-old object of these attacks professes to be mystified by all the fuss. To Chatterjee’s mind, such attacks are just petty and bothersome. I may be wrong, or I may be right, Chatterjee says. It’s just a hypothesis that I found something that is the earliest bird. The thing is, nobody has discussed the material in my paper. Instead they are dealing with the peripheral subjects, which really bothers me. Some people who have never seen this specimen have made all kinds of comments. I’m really getting very tired.

The truth is that these critics are quite willing to discuss the material in his paper, and if Chatterjee is bothered by peripheral subjects like questions about his methods, many paleontologists--including his defenders--think he’s partly to blame for the controversy. I think he’s laid himself open to a lot of criticism because of the way he’s handled it, says Nicholas Hotton of the Smithsonian Institution, who describes himself as a close friend of Chatterjee’s. I mean, he just comes out flat-footed and says it’s a bird. A lot of the acrimony was avoidable.

A bold claim about the origin of birds simply makes paleontologists go berserk. There are a number of reasons for their extreme reaction, but much of the blame must fall on the birds themselves. Alive, birds are magnificent products of evolution. Everything in their body is perfectly engineered for conquering gravity, from their enormous chest muscles to the microscopic details of their feathers. When birds die, however, they make terrible fossils. The feathers rot, and the hollow, slender bones are easily crushed. It’s a miracle that there are any bird fossils at all, let alone the few that exist.

Before Chatterjee came along, all the viable theories about where birds come from were essentially based on one of these fossils: Archaeopteryx. Found in 1861, Archaeopteryx was a spectacular case of beginner’s luck for paleontology, which at the time was barely an organized science. One day about 150 million years ago this creature fell into a lagoon in what is now Germany. The stagnant water allowed mud to cover the animal gently, preserving not only its bones but also the impression of its feathers in microscopic detail. While its feathers and wings were clearly those of a bird, other features--such as its teeth, its long, bony tail, and the fingerlike bones at the edge of its wings--were those of a reptile.

Using Archaeopteryx, paleontologists have offered several different theories of avian origins. The one embraced by today’s textbooks derives largely from a shock of recognition experienced two decades ago by paleontologist John Ostrom of Yale. One day in 1970 Ostrom was sitting in a Dutch museum, studying some fossils from Germany identified as the wrist and hand bones of a pterosaur, an ancient flying reptile only distantly related to dinosaurs. It didn’t take long for Ostrom to recognize that this wasn’t a pterosaur at all, because the details of the bones didn’t match those of other specimens he had looked at elsewhere. He tilted the fossils in the light and felt a rush of adrenaline when he saw the faint outline of feathers. What he was in fact holding, he realized, was the world’s fourth known Archaeopteryx. (Six are now known.)

This discovery prompted Ostrom to return to other Archaeopteryx specimens and look more closely than before at the bone structure. And then I said, ‘Whoa, wait a minute. All of this anatomy--hey, I’ve seen this before on a larger scale.’ He had seen it in dinosaurs.

Six years earlier, in southern Montana, he had dug up a 110- million-year-old dinosaur, which he named Deinonychus. At the time no one had ever seen anything like it. Though a carnivore, it wasn’t a lumbering giant like Tyrannosaurus rex. Instead, it was a human-size, lightweight bipedal killing machine. Everything about it was designed for high-speed slaughter, down to the claws on its feet, which looked like gigantic can openers and were used to tear open the guts of its prey.
The arms, wrists, and hands of Deinonychus looked distinctly like those of Archaeopteryx. Even to an untrained eye, the similarity is clear. Ostrom compared other parts of the two skeletons--the hips, the ankles, the shoulder bones--and decided they were so similar that Deinonychus and Archaeopteryx had to be related. Archaeopteryx lived 150 million years ago- -40 million years before Deinonychus--so obviously Deinonychus couldn’t have been its ancestor. Presumably, some slender bipedal dinosaur that lived before both of them was their common grandparent. And since Archaeopteryx was well on the way to being a fully modern bird, that same dinosaur was the great-grandparent of everything from condors to cockatoos.

For many younger paleontologists, Ostrom’s discovery was a classic moment when science takes a jackknife turn. It sends chills down your back when you look at Archaeopteryx and Deinonychus, says Paul Sereno of the University of Chicago. You can understand the excitement Ostrom must have felt when he saw it. Their shared traits are frighteningly unique.

Sereno’s generation has come into its own since Ostrom hatched his theory, and it has supported him with a new method called cladistics. Cladistics uses computers to map dozens of traits shared among different species and to figure out how closely different animals are related to one another. The diagrams it constructs, called cladograms, are family trees that don’t actually show who is descended from whom. Rather they show which animals among a group of various creatures have the greatest number of significant shared traits--bone shapes, number of legs, or other anatomical features--and the next greatest number, and the next. If in a group of three animals all share trait A but only two also share trait B, cladists assume that the animal lacking trait B took off on a different evolutionary path from the other two animals, who therefore are more closely related.

Cladists such as Kevin Padian of the University of California at Berkeley and Jacques Gauthier of the California Academy of Sciences have examined 187 different traits of birds, and they’ve built them into bird and dinosaur cladograms. They agree that lightly built dinosaurs like Deinonychus are the closest relatives to birds. Great bipedal bruisers like T. rex are a little more distant, four-legged vegetarians like Apatosaurus are further away, and nondinosaurian reptiles are even further. Birds, concludes Gauthier, are as much dinosaurs as humans are mammals.

Researchers have combined these cladograms with known dates of fossils to sketch the evolution of birds. First, perhaps 240 million years ago, primitive dinosaurs split off from other reptiles. Early on they divided into several groups, one of which consisted of two-legged carnivores. Gradually some of these dinosaurs became very birdlike, and sometime between 200 million and 150 million years ago one of them-- Archaeopteryx or a close relative--became a true bird. For the next 80 or so million years, birds and dinosaurs like Deinonychus evolved slowly on separate tracks. Birds lost their teeth and the claws on their wings, their fingers fused together, and they became better fliers. By 65 million years ago birds were so different from dinosaurs that they survived whatever catastrophe wiped out their kin.

What this means--if Ostrom and the cladists are right--is that the dinosaurian model didn’t become obsolete. In fact, if you consider that there are 8,700 species of birds alive today--twice as many as there are mammal species--dinosaurs remain one of the most successful life-forms on the planet.

During the early 1980s, as Gauthier and Padian grew trees in their computers, Chatterjee was pulling bones out of Texas bluffs. The fossils he found dated back 225 million years, to a time when the area around Lubbock was a lush floodplain crisscrossed by rivers flowing west to a 300-mile-long inland lake. Animals living upstream would occasionally be overwhelmed by flash floods and carried for miles before they were dumped. Today they have become great piles of bones for paleontologists like Chatterjee to pick through.

At that time dinosaurs had begun to diverge from other reptiles, but they were still primitive. Carefully working his way through the bones, Chatterjee was able to find and name several new species. He’s established quite a collection, says Sereno. In any evaluation of archosaurs [dinosaurs and their ancestors], you have to take his work into account.

In 1983 Chatterjee found some bones, broken into many fragments, that he thought belonged to some run-of-the-mill dinosaur. It wasn’t until two years later that he started to toy with the fragments and piece them together, and as he did he began to notice some odd things. The shoulder bone, for instance, was much longer than those of most dinosaurs but a lot like those of modern birds. And the neck vertebrae had a saddle shape, one peculiar for dinosaurs but normal for birds--it makes their necks flexible.

As Chatterjee assembled the shattered bits of skull, he found something that for him was even more striking. Behind the eye of a dinosaur are two holes in its skull, divided by a bony strut. In the course of developing a more flexible jaw, birds have lost this strut. I noticed there was just one hole, says Chatterjee. This is the most distinctive feature of the bird skull. He believed he could even see little knobs in the arms of the skeleton where feathers would have been rooted. By the end of 1985 he thought there was a pretty good chance that he had actually found a bird.

The National Geographic Society funds Chatterjee’s work, and he was obligated to write a report to the society detailing his find. When the people at the society read that Chatterjee thought he’d found the first bird, they wanted to call a press conference. Before they did, though, they thought it would be prudent to get some reactions from a respected paleontologist on the outside. They called John Ostrom.
They asked me if this was something they should do, and I said, ‘I don’t know,’ Ostrom recalls. To say anything about the bones, he told the society, he would have to see them. So they flew me out to Lubbock.

As Ostrom remembers it, the visit was rushed and harried. He could spare only a few days from his own work, and the society was pressuring him for a quick verdict. The bones were so smashed that you could make almost anything of them, he says. I had only a few minutes with each bone. Chatterjee was telling me what things were--to save time-- and I gave him the benefit of the doubt. But one has to approach this situation as free of prejudices as possible. I wish the circumstances had been different.

Ostrom would have preferred to spend a few weeks or months alone with the bones, away from the influence of a hovering paleontologist whose enthusiasm might sway him toward unwarranted conclusions. But Ostrom had agreed to the situation, so now he was stuck with saying something. He gave the proceedings a very small blessing, saying that yes, the bones looked birdlike. But he didn’t think there were feather nodes, and he pointed out that the bones were very fragmentary. Without Ostrom as a wholehearted cheerleader, National Geographic switched from a press conference to a press release.

On August 13, 1986, the society issued a release that made the identification sound like a fait accompli. Chatterjee, it read, is convinced that the bird--he will name the genus Protoavis, or ancestral bird--could hear and communicate with others of its kind. And, he says, it might have had brilliant plumage for camouflage in the forests. Elsewhere the release claims that Protoavis, although not a long-distance flier, could easily have flown from tree to tree and navigated from the ground to the tallest branches to escape predators. Not once did the press release mention Ostrom’s reservations.

A reporter who reads a press release like this won’t ignore it. The publicity began to snowball. One article appeared on the front page of the New York Times, while others showed up in the Washington Post, Time, and Scientific American, to name a few. Texas Fossil Identified As Earliest Known Bird, the headlines proclaimed; Patriarch of the aviary; Fossil Revisionism; Fossil Bird Shakes

Evolutionary HypothesEs. Some early articles did mention the reservations of paleontologists such as Ostrom, but the brute force of all the column inches made Protoavis sound like a great step forward for paleontology, an unusual discipline in which setting the science back by several million years is a sign of progress.

To judge whether or not Chatterjee was right, paleontologists had two options: they could either read the paper he would write or look at the bones themselves. Since no paper seemed to be forthcoming, the paleontologists started making pilgrimages to Lubbock to check out the fossils.

Few were satisfied with what they saw. Gauthier thought the bones were an ambiguous mess. When he visited, Chatterjee showed him a bone he confidently identified as a piece of the palate. But Gauthier was baffled: I looked at it and didn’t know what it was. The skeleton is just smushed and mashed and broken. Michael Parrish of Northern Illinois University says, I wish the elements identified as wings were better preserved. The material wasn’t complete enough for me to be convinced.

This wasn’t a dinosaur fossilized in some lifelike pose; to paleontologists this was a Rorschach test in which reality was in the eye of the beholder. And Chatterjee had not photographed the bones as they were found; he had followed standard paleontological practice and made only simple sketches. The material is totally removed from the matrix, and there’s no existing evidence about whether the bones were articulated or dispersed, complains Ostrom. All we have is one man’s word. Like Ostrom, other complaining paleontologists wanted to borrow the bones and look at them for themselves for a long, long time. To ask for the bones, though, would break a rule of fossil etiquette: until a researcher publishes his paper on a discovery, the bones he finds are his. After publication paleontologists frequently lend fossils to other experts for their own long-term study. So paleontologists sat on their hands and waited for the other shoe--the paper--to drop.

Years passed, and while Chatterjee gave brief presentations at a couple of meetings, nothing on paper came out of Lubbock. Paleontologists became dismayed by the silence, and Ostrom became furious. It’s a cold fusion phenomenon, says Ostrom. I’m very unhappy with people who go to the New York Times or whomever before they’ve completed their analysis. I was appalled by the magnitude of his claim without any published material on it.

Chatterjee says he did nothing wrong or, at worst, almost nothing. I’m really just a field worker, he says. They’re using this old argument that I went to the press, but I never went to the press. I did not do the press release. I never called any journalists. We have to sign a form when we get a grant from National Geographic saying that they will do the press--we cannot do anything. It’s entirely their ball game. A preliminary report is my only fault. Chatterjee also thinks his critics are being hypocritical when they scold him for news coverage received before the publication of a paper. Everybody does the same thing. It’s standard practice. Even in the case of John Ostrom it happened.

In the New York Times of December 4, 1964, there is an interview with a younger Ostrom about Deinonychus, the fossil he had found the previous August. He had only fragments at that point. Using bits and pieces of bone, however, the article ran, Dr. Ostrom has reconstructed a foot and some of the animal’s joints. Ostrom was willing to talk at length about the dinosaur’s huge claw and other features that made it an exceptional animal. It wasn’t until five years later, however, in 1969, that Ostrom published his first papers on Deinonychus. While his claims were nowhere near as grandiose as Chatterjee’s, the similarities of the situations are striking.
Most paleontologists agree that when they unearth an important fossil there is always a certain amount of tension about how to handle the publicity. Ask National Geographic about the press release--they’re the ones who screwed up, says Walter Bock of Columbia University. They’re interested in publicity, and Chatterjee would have been in a difficult position to say no. The cold fusion complaints are idiotic. So he took a couple of years. People finish up studies as they want to. They don’t have to finish up for other people’s convenience.

Chatterjee says he took so long with the bones because he was being very careful. If I made mistakes, people were going to catch me. I’m not a bird specialist, so I had to study them for a while. Other researchers who have seen the bones are willing to come to Chatterjee’s defense. I told Sankar to publish a short piece in Science or Nature, says Larry Martin of the University of Kansas. But I understand why he was reluctant. You can’t imagine how intense the attacks are from the dinosaur people. I had one grad student who gave up and became an oil geologist instead because of it.

Martin, who was trained as an ornithologist, has a number of reasons for being sympathetic to Chatterjee. He too has been attacked by the dinosaur people. Martin is one of a handful of researchers who have maintained throughout that Ostrom and the majority of paleontologists are wrong. Birds do not descend from dinosaurs, they say; birds have a much older and less romantic heritage, coming from primitive reptiles known as thecodonts, or possibly from even earlier creatures. So for Martin, the unearthing of Protoavis is a blessing.

Martin argues that Ostrom’s comparisons of Archaeopteryx with dinosaurs like Deinonychus are rife with misinterpretations of the fossils because of what he sees as Ostrom’s relative ignorance about birds. To Martin, the similarities between Archaeopteryx and some of the thecodonts, as well as other dinosaur predecessors, are more significant. Those bird- dinosaur cladograms, Martin insists, don’t give cladists any mystical power over the fossils, since if you put garbage into a computer, it spews garbage out. Bock, though he doesn’t think there’s enough evidence yet to support ancestral claims for either dinosaurs or thecodonts, agrees with Martin about cladistics experts: They’re full of crap. They just don’t analyze characteristics properly. There are lots of serious problems that they just overlook completely. Often the cladists are accused of misidentifying traits, picking out the ones that support a particular theory while ignoring ones that contradict it.

Sam Tarsitano, a biologist from Southwest Texas State University, cites another reason for doubting the bird-dinosaur connection. Tarsitano looks at how easily flight could have evolved in different animals. Animals obey the laws of physics, and we can predict what will work and what won’t, he says. When the dinosaur theory is examined in this light, Tarsitano says, it just doesn’t make sense.

For one thing, it’s hard to fly when you are big. The smallest Troödon (a slimmer, oft-mentioned alternative to Deinonychus as an avian cousin) found so far is about the size of a turkey, and smaller dinosaurs-- which don’t have as many similarities to birds--are the size of a chicken. Even at this size the benefits of primitive feathers would be erased by the weight of the animal.

And even if there were a miniature dinosaur trying to jump around, Tarsitano says, the proportions of its body would be exactly what you wouldn’t want if you’re aiming for aerodynamic design. In dinosaurs part of the hip sticks out, facing either downward or forward. If a dinosaur leaped into the air and tried to flatten itself into a graceful flying body, it would be foiled by this huge bulge, which would produce enormous amounts of air turbulence. Birds, on the other hand, have swept- back hips, and when they take to the air, their bellies are smooth.

Birds also have a center of gravity closer to the front of their body, because their shoulders and wings are as big or bigger than their lower body. The birdlike dinosaurs were ground runners, and as a result they have huge hips and legs and scrawny arms. Go out and buy a toy glider, Tarsitano suggests, and take the little weight they put on the front and put it on the back. It’ll flip over when you try to fly it. Really, to make it like a dinosaur, you should put two or three weights on.

A thecodont called Megalancosaurus looks more like a flier to Tarsitano. This small, four-legged, tree-dwelling creature, just 10 or 11 inches long, had the right kind of center of gravity. Instead of running up to speed on the ground as a dinosaur would have had to do, it could simply have leapt out of trees. Feathers would have made it more buoyant and eventually helped it to navigate from tree to tree.

Tarsitano and Martin came up with these ideas long before Chatterjee came up with Protoavis. But when the early bird hit the headlines like a sparrow against a windshield, it seemed to them the perfect argument in their favor. If this turns out to be a bird, it raises total havoc with the idea that birds evolved from a group of dinosaurs, says Bock. It means that fully developed birds were living 225 million years ago--115 to 150 million years before Deinonychus and Troödon, the first known dinosaurs that are noticeably birdlike. If Deinonychus and Protoavis indeed arose from common stock, one might reasonably expect an older birdlike dinosaur--a creature with an earlier perch on the Deinonychus branch of the family tree--to have turned up at some point. After all, the lineage had to start someplace. But no dinosaur older than Deinonychus has ever been found that fits the bill.

In addition, 225 million years ago was the dawn of the age of dinosaurs. If Protoavis was a bird, and dinosaurs were bird ancestors, then dinosaurs would have had to evolve awfully fast. The first dinosaurs were large, ground-based reptiles, and some of them would have needed to metamorphose into creatures with the incredibly sophisticated and specialized anatomy for flight in just a few million years. That’s what I call a silly conclusion, says Martin. It would be much easier, in his view, for some thecodont to start earlier and evolve directly into Protoavis and then birds, while dinosaurs went their own way.

Most of Sankar’s opposition comes from dinosaur people and most of his support comes from bird people, says Hotton. The bird people are hostile to the dinosaur theory, and that puts a political angle on it. I think that’s got something to do with why they support the thing as a bird, because it’s so early. In fact the bird people have so much respect for Chatterjee that they have asked him to deliver a speech at the 1994 meeting of the International Ornithological Congress in Vienna.

The dinosaur people get irritated when gadflies like Martin and Tarsitano are even mentioned. Their ideas are moot among most of my colleagues, says Sereno. The sad thing is they haven’t put their ideas in a modern form. There’s been a revolution, and we’ve moved into a rigorous era of science. Now you take your characteristics, and you score the species, and you see who’s related and who isn’t.

With the stage thus set for conflict, and paleontologists impatient for a paper to chew over, Chatterjee finally hit print last year. He came out with a fat monograph in the Philosophical Transactions of the Royal Society of London, weighing in at 66 pages and packed with reconstructions. Chatterjee included photographs and drawings of all of his bones, but the paper itself dealt only with the skull of Protoavis, leaving the rest of the skeleton for a later report. The heat Chatterjee had felt from other paleontologists hadn’t made him back away from his claims. He titled his paper Cranial Anatomy and Relationships of a New Triassic Bird from Texas--no ifs, ands, or buts about it.
Unquestionably, he wrote, the head belonged to a bird. It had the same kind of air tubes in the skull that birds have, a big brain, and eyes situated so as to promote sharp stereovision. Like modern birds, it could pull its upper jaw up--something that helps a bird snatch a crawling bug or pick seeds more accurately. Chatterjee even drew a fleshed-out sketch of Protoavis’s head--it looked vaguely like that of a goose.

Now that his paper is out, his opponents have taken off their gloves. Ostrom simply thinks the paper is terrible. I don’t think the paper proves a damn thing, he says. Rowe says it wasn’t even worth publishing. The paper shows that this isn’t a bird, he says. It’s not even close. It’s interesting that he chose to publish it outside the United States, where the reviewers didn’t even see the bones.

Many critics start their attack with the wishbone, an important clue to a bird fossil, since nearly all flying birds back to Archaeopteryx have one. A wishbone stretches across the chest and anchors to each shoulder. It helps a bird fly by acting as a spring, getting compressed in the downbeat of the wings and then pushing them back up. Chatterjee does have an illustration in his paper of something that clearly looks like a wishbone, a V-shaped bone with a healthy knob at its base. This knob, called a hypocleidium, is familiar to anyone who’s ever eaten a chicken.

There is, however, one problem: Chatterjee actually has only a fragment of the knob. All the rest of the wishbone is extrapolation. Ostrom considers this kind of identification absurd. Parrish says the bone fragment isn’t a wishbone knob at all, but a knob from the tail of a trilophosaur, a reptile that became extinct 5 million years after Protoavis supposedly lived.

Chatterjee’s critics use this kind of argument often, claiming that Protoavis is a blend of several different animals that Chatterjee has formed into a bird. The thigh bone, says Rowe, probably belongs to a young ceratosaur (an early dinosaur), and the hand looks like the foot of a crocodilelike reptile. And given that the bodies had been flushed down a river, his critics say, such a mix could well have taken place.

Gauthier wonders why Chatterjee is so willing to say that the bony strut common to dinosaurs is missing in Protoavis, when the skull is incomplete and shattered into pieces to start with. You could say it doesn’t have half a backbone or a right leg since he didn’t find them, Gauthier says. Chatterjee, he adds, also performs a wild balancing act with his inferences, stacking one on top of the other. From his reconstruction of the skull, he says that the two eye sockets are oriented toward the front. That, he contends, means the bird had stereovision. And therefore, he reasons, Protoavis was a predatory bird, designed to look ahead and track prey rather than watch for sneak attacks from the sides. All of those claims rest on the bones Chatterjee has, but Gauthier insists the skull is too smashed to interpret reliably. This is something that looks like it’s been jumped up and down on a couple of times and shaken up and had some parts of it taken away, he says.

It’s real roadkill, says Rowe. Paleontologists walk a delicate line. We do have fragmentary material, and we do try to squeeze as much from the data as we can. There’s always the temptation to go a little beyond the bounds of what the actual specimen will support--and that’s the line that Sankar crossed badly. The basic argument is that he points to a lot of characteristics as being avian, but if you look at the skeleton, they’re all contingent on his reconstruction. There are a bunch of ways you could put it back together. And he wants it to be a bird.

There should be something about a bone that drags you kicking and screaming to say that it’s a bird’s, says Gauthier--not the other way around. Even Chatterjee’s defenders don’t have his kind of confidence in his fossils. Martin suggests that it may not have had feathers, in which case he thinks it was a thecodont on the verge of becoming a bird. He’s very enthusiastic, more than self-critical, says Bock of Chatterjee. But Bock believes Chatterjee is right about the saddle-shaped vertebrae on Protoavis, and only birds are known to have them.

As if this fight weren’t complicated enough, there’s a third side to it. In Chatterjee’s paper he actually argues that Protoavis supports the idea that birds are dinosaurs. He had a computer generate a cladogram based on the skull characteristics, and it wedged Protoavis between birds and Archaeopteryx, with other dinosaurs on the adjacent branches. But Chatterjee is almost alone on this one. Gauthier says Chatterjee’s cladistics are bad. He’s taken the skull without including the rest of the skeleton, he says, and that violates the principle of total evidence. He also says that it’s wrong for Chatterjee to plug characteristics into his computer that aren’t clear-cut from the evidence but are the result of a lot of reconstruction and theorizing.

Chatterjee hopes to publish his next paper in Transactions sometime next year. In it he’ll discuss all the other bones, including a new bit of Protoavis that he’s recently dug up, a fossil that he says is the winning side of a wishbone pull: one arm plus a healthy knob. At that point all the bones will be fully described in print, and Chatterjee will be obligated to grant other researchers extensive access to them. Paleontologists have been lusting for that moment. I’m very anxious to get the stuff since it will be public domain, says Gauthier.

But public domain does not necessarily mean instant and easy access. Ostrom says he has written to Chatterjee to be the first in line to get the bones and that Chatterjee has said no dice. I’ve been informed by Sankar himself that if I want to look at the material, I have to go out there and live in Lubbock, he says with distaste. Taking Chatterjee to task publicly in a brief commentary in Nature, Ostrom wrote that such behavior was intolerable, and he demanded that Chatterjee give other paleontologists reasonable access to the bones by sending them to the Smithsonian Institution.

Chatterjee did, in fact, bring the bones to the Smithsonian for researchers to examine in the summer of 1988. And he is smarting from Ostrom’s public attack, since Ostrom’s is a powerful voice in an uncomfortably small field. This isn’t science, Chatterjee says. He’s playing tricks. According to Chatterjee, Protoavis is what’s called a type fossil--the yardstick of a species against which all others of its kind will be compared for authenticity. Wherever the type specimen is, people go and study there. If I want to study Archaeopteryx, I have to go to Germany. No museum would lend a type specimen. Ostrom is a curator. He knows that.

Bock backs up Chatterjee on this point: He has every right to keep the damn bones. Lubbock has a natural history museum. Why shouldn’t they keep them? If Ostrom doesn’t like it, it’s too damn bad. Ostrom, of course, thinks there’s a very good chance that Protoavis is not a type of anything.

If the bones are going to stay at Texas Tech, Rowe has a suggestion that he thinks might satisfy everyone: I’d love to see the National Science Foundation sponsor a symposium in Lubbock, with all the experts there, and get them to look at the specimens. Some positive things would come out of it--we’d figure out whose bones these really are. The outcome would be unequivocal.

Currently, the only unequivocal aspect of the Protoavis affair is that it has left Chatterjee in a precarious situation. Sereno, who has kept his distance from the fight, thinks the attacks on the Texas paleontologist are getting out of hand, focusing more on personal style than on science. He worries that Chatterjee is becoming the victim of a witch-hunt. Anyone should feel free to say whatever they want, Sereno says. To make it a personal point, to try to trim someone down to size, is ridiculous.

Perhaps Martin, a grizzled veteran of many fights over the origin of birds, is the one who sums up the situation most neatly: He’d be better off if he’d never found the damn thing.
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