Is Auca Mahuevo the Real Jurassic Park

In November of 1998 just before Thanksgiving, two articles about the nesting site at Auca Mahuevo announced what we had found. One was the scientific paper in Nature; the other was a popular article that was published in National Geographic. The National Geographic Society had helped to fund our 1997 expedition, and they wanted to let the public know what we had found.

To let other media outlets know about the discovery, we also scheduled a news conference at the American Museum of Natural History on the day that the articles were released. The museum had sponsored the expedition, and at the time we both worked there. We were fortunate that Rodolfo was able to come up from Argentina to join us for the news conference.

Setting up a news conference requires a lot of work. The public relations department of the museum spent several weeks contacting journalists and correspondents at newspapers, magazines, television stations, and radio stations, letting them know that we intended to announce a major discovery about dinosaurs. Most of this responsibility fell to Elizabeth Chapman, the director of media relations for the museum at the time.

Elizabeth is a diminutive dynamo of energy and enthusiasm for anything scientific that goes on at the museum. Her job was to encourage media coverage of the institution's scientific research, and there is no subject that she loves more than dinosaurs. She developed that love as a small child. When she used to visit her grandparents in Pittsburgh, they would take her to the Carnegie Museum, and she would demand that her grandmother read every word on every label in the dinosaur halls. One year, her grandmother tired of this exercise and failed to read the last few sentences on one of the labels. Elizabeth immediately protested that her grandmother had not read all of the text. Elizabeth had memorized all of each passage.

Elizabeth had joined us for a few days at the end of our expedition in November 1997 so she could get a better idea of what we had found. She had wandered around the site with childlike amazement and glee, picking up eggs off the surface of the flats and inspecting them for remains of fossilized skin and embryos. From her curiosity and wonderment, we knew that this was one of the most satisfying moments of her career.

When Elizabeth had the chance to help us announce our discovery, she pulled out all the stops. For weeks before the press conference, she contacted media outlets all over the world to let them know that a significant announcement was in the works. The day before the conference, she faxed hundreds of press releases to reporters around the world. Of course, there was no guarantee that all the correspondents would be interested, so she was always cautious with us about how many news organizations would respond.

On the day of the press conference, we arrived early to set out some of the fossils for the reporters to see and then calmly went back to our offices to wait. We were sure that some reporters and television crews would show up, but we didn't think it would take too long. As the hour arrived, we walked into the room where the conference was to be conducted. To our amazement, the room was packed solid with cameras and reporters. At least fifty reporters and ten television cameras were crammed throughout the room, with camera technicians jostling each other for prime positions as we walked in to begin our presentation. We glanced at each other in stunned amazement.

Elizabeth began to brief us about who had shown up; the list was staggering. The New York Times, Time, Newsweek, and the Associated Press had all sent reporters, as had numerous other local New York newspapers. CNN, ABC, NBC, CBS, the Associated Press, the Discovery Channel, and several local New York television stations had sent camera crews. Even several publications and media outlets from

South America attended. The blinding lights from the cameras flashed on, and the show began.

The juxtaposition of the desolate scenes from the field and the media frenzy in the conference room seemed rather surreal. Little did we know when we had traveled to that remote corner of Patagonia that we would bring back fossils of the tiniest giant dinosaurs, who would become instant media celebrities 80 million years after they had died.

After we were introduced, we showed some slides and a video of the site as we described the kinds of fossils we had found. This presentation took about half an hour before we opened the floor up for questions. The questions and subsequent interviews went on for another three hours. By midaftemoon we were fried and retreated for lunch to our offices. But the wave of publicity was just beginning to crest. During the news conference, dozens of reporters who had not been able to attend called the museum to ask questions and get quotes from us. The phone calls continued throughout the afternoon. By evening, we were exhausted and hoarse, but we still had to ride down to the BBC studio to do a live interview for their late-night news on radio and TV By the time that was over, we had been on stage for almost nine hours straight. It was definitely time for a drink.

That evening, numerous members of the field crew and the media, along with some of our other colleagues and friends, gathered at a Spanish restaurant downtown. InfoQuest, one of the foundations that had sponsored the expedition, had arranged for an informal party to celebrate our announcement. When we arrived at the restaurant, at about 8 P.M., several guests said that they had already seen clips from the news conference on TV. It was all quite gratifying, but the almost instantaneous nature of the coverage was also rather numbing. We hoped that, in all the commotion, we hadn't said anything too stupid in front of the cameras. About 10 P.M., the party broke up, and we went home. But the onslaught of coverage would continue the next day: at five-thirty the next morning, we had to show up bright and cheery for an appearance on Good Morning America.

We awoke to a torrent of publicity. In addition to the scientific report that was published in the November 19,1998, issue of Nature, the National Geographic article appeared. The story made headlines around the world, with front-page articles in The New York Times and the Los Angeles Times; television segments on ABC TV's Good Morning America, the CBS Evening News, and BBC TV; articles in Time and Newsweek; and dozens of stories in newspapers and magazines, on radio shows across North America, Europe, Japan, and Latin America. In all, Elizabeth estimated that this tsunami of media attention inundated about 100 million people.

All the attention was great, but some of the coverage was completely unanticipated. A few days after our announcement, for example, The Daily Show, a parody of the nightly television news on the Comedy Central network, surprised us all with their interpretation of our discovery. They suggested that what we had really found was the world's oldest known abortion clinic. Another one of our favorite accounts appeared in one of the tabloids. The paper had printed pictures of our eggs and the embryonic dinosaur skin and quoted a fictitious paleontologist, who claimed he had discovered living embryos of the giant sauropods, which he was now incubating. Eventually, when they hatched, he said, he intended to set up a game preserve where they could grow up and reproduce —a real Jurassic Park. We wish the report had been accurate, but it was clearly an exercise in science fiction rather than science. Nonetheless, similar questions arose during many of our interviews, which was not surprising given all the recent advances in cloning and the popularity of Jurassic Park—both the novel and the movie.

Let us take a moment to address this issue here. In the movie Jurassic Park, numerous kinds of extinct dinosaurs are brought back to life by reactivating the genes of these dinosaurs after the genes have been recovered from the bodies of mosquitoes or other bloodsucking insects preserved in amber. The scientists extract the dinosaur blood horn the fossilized insects, separate the dinosaur DNA, which contains the genes, from the blood, and use that to re-create the dinosaurs. But how realistic is this scenario in light of science's recent success in cloning sheep, mice, and even monkeys?

It is undeniably true that many kinds of small fossil animals and plants can be preserved in amber, which is simply sap from ancient trees that has been buried in the earth for millions of years and has hardened into a yellowish, clear solid. Insects are one of the most common kinds of animals to be found in amber, because they became trapped in the sticky sap while foraging for food. Amber is an unusu ally good material in which to find fossils because delicate structures are often preserved, such as fine hairs on the insect's body and the pattern of veins in the wings. These soft tissues are not commonly preserved in fossils buried in sandstone or mudstone. The exceptionally complete fossilization of insects in amber provides scientists with many extraordinary clues to identify ancient insects and to analyze where their groups fit on the evolutionary tree.

In fact, however, no Mesozoic insects in amber have ever been found with blood inside them, and most insects in amber lived much later than the dinosaurs seen in the movie Jurassic Park. As mentioned earlier, dinosaurs originated in the Triassic period. The earliest-known dinosaurs, such as the small carnivores Herrerasaurus and Eoraptor from Argentina, lived about 230 million years ago. Unfortunately, we have never found amber with insects inside from rocks that are this old. The next period during the Age of Dinosaurs was the Jurassic, when the first giant, plant-eating sauropods, such as Bra-chiosaurus, lived, as well as fierce carnivores such as Allosaurus. But no Jurassic amber with biting insects inside has ever been discovered. So despite the name of the book and the movie, there is not even any insect-bearing amber available to use in trying to clone dinosaurs from the Jurassic period.

There are, however, some biting insects preserved in Cretaceous amber. This was the age in which Tyrannosaurus, Velociraptor, Tricer-atops, and Ornithomimus lived, as well as the sauropods from Auca Mahuevo. A few small biting insects called midges are known from amber this old, but none have been found with blood in them, and none of these have been found at Auca Mahuevo. At present, the oldest known biting insect preserved in amber is about 125 million years old. It is possible that paleontologists will eventually find Triassic, Jurassic, and Cretaceous insects with blood inside them, but it would be rare and, based on experience, unlikely.

One reason for this improbability is that blood breaks down quickly after an animal dies. Rotting actually begins within minutes after death, which is why bodies must be embalmed if a person is to be buried and is also why blood that is donated for operations must be maintained under strict temperature controls. So even if a blood-filled insect were to be discovered in amber, the blood would have had to have been perfectly preserved in amber for more than 65 million years to be useful for the purpose depicted in the movie Jurassic Park. This would be unlikely because, as the amber is buried deep within the earth during fossilization, temperatures can easily reach several hundred degrees, which would surely destroy the blood cells. An additional problem is that the amber itself often contains natural cracks, increasing the chances that contaminants in the groundwater that flows through the rocks in which the amber is buried will damage the dinosaur genes in the blood.

Another problem is that the insect would have had to die before the dinosaur's blood was digested in its stomach, because digestion would also have damaged the dinosaur's genes. What's more, there is no guarantee that the insect's last meal would have been the blood of an extinct dinosaur, given that many other kinds of animals also lived during the Mesozoic, including turtles, lizards, crocodiles, pterosaurs, birds, and even our own early mammalian relatives. Furthermore, it would be no easy task to remove the dinosaur's blood and genes from the insect inside the amber. For the purposes of cloning in the movie, the dinosaur's genes would have to be kept separate horn the genes in the insect's body. But since we would have to cut through the insect to get at the dinosaur's genes, it would be difficult to keep the tissues of the two animals separate and uncontaminated.

But assuming that all this could be done, molecular biologists have recently developed a technique called polymerase chain reaction (PCR) to duplicate the genes enough times to produce enough genetic material with which to do some experiments. Most of the research done in labs around the world using this technique is directed toward comparing the genetic codes of different animals in order to establish their evolutionary relationships. To date, the oldest insect DNA that has successfully been duplicated is genetic material from a termite preserved in amber between 25 and 40 million years ago. That was a remarkable accomplishment achieved by molecular biologists working at the American Museum of Natural History in New York. Nonetheless, that termite lived long after the Mesozoic ended 65 million years ago.

The problems don't end here, either. An animal's genetic code is like a book containing information about how to build that particular animal. The chromosomes are like the chapters of the book; genes are sentences; and nucleic acids are letters of the alphabet. Because

DNA molecules break apart so easily, the best that could be hoped for in separating dinosaur DNA from the insects is to find two or three hundred letters of the genetic code still stuck together. This would constitute an ordered sequence representing less than a millionth of the whole genetic code—not nearly enough to make any sense of the whole book. So finding a piece of extinct dinosaur DNA inside the body of an insect preserved in amber would be like finding a sentence from a long book that had been cut up into millions of pieces. With just that one sentence, we would have almost no chance of understanding the meaning of the book, because we would be missing millions of other sentences, thousands of other paragraphs, and dozens of other chapters. The scientists in Jurassic Park avoid this problem by adding DNA from living animals to the dinosaur DNA. However, we do not know nearly enough about how DNA works to be able to patch pieces of living and extinct DNA together like this. Since each kind of animal has its own genetic code, the result would almost certainly be gibberish, not a sensible book specifying how to resurrect an extinct animal.

But let's make believe that we were somehow able to get all the pieces of the genetic code for an extinct dinosaur out of the fossilized insect in amber. Could we re-create the dinosaur then? Again, the problem would be one of putting the letters, sentences, and chapters back together in the correct order to make a sensible book. Thus, even if we had all the sentences (all the short segments of DNA in the genetic code), our challenge would be similar to putting a huge puzzle back together when all of the pieces are similarly shaped. It would be virtually impossible to put them all back together in the correct order. But even if all the DNA segments could be assembled in the proper order, the genetic code is only one aspect of what is needed to re-create an extinct dinosaur or any other living animal. The mother's body provides a whole chemical and physical environment that is needed for the embryo to develop within before birth. The scientists who cloned Dolly the sheep, for example, used the body of a living female sheep to nourish the developing embryo. But we have no mother's egg within which an extinct dinosaur embryo can develop. Thus, we are missing an essential component in the process. Without the supporting environment inside the egg, we would end up with just a bunch of chemicals floating around in a test tube.

This problem was fancifully solved in Jurassic Park by placing the dinosaur DNA inside an egg cell of a female crocodile. This makes a bit of evolutionary sense because the crocodile is the closest living relative of extinct dinosaurs, except for birds. It would have made even more sense to stick the dinosaur DNA inside the egg cell of a female ostrich, but even this wouldn't have worked. Not enough is known about what triggers and controls an embryo's growth and birth to successfully duplicate an animal that has been extinct for 65 million years.

So our chances of re-creating an extinct dinosaur are not good. In fact, there is realistically no chance at all. Could that change in the future? Perhaps... in the far distant future, but many momentous scientific breakthroughs would have to be made to do so. Realistically, those breakthroughs are impossible for us to envision and, in all probability, will never occur. Molecular biologists and paleontologists are constantly asked whether extinct dinosaurs can be cloned. As our press conference demonstrated, reporters often like to probe endlessly, trying to force us to admit that the possibility exists. After extensive badgering, when one of the museum's scientists was asked whether he thought there was just a slight chance of this all eventually coming to pass, he thought for a second and exasperatedly replied, "Yeah, and someday monkeys might fly out of my butt, too." Naturally, we hope, for our colleague's sake, that the chances of that occurrence are, indeed, equally low —even in the years to come. Although many scientists would have offered a more politically correct answer, his response reflected the overwhelming consensus among scientists that an actual Jurassic Park is unlikely to become a reality.

Having survived the media blitz, our thoughts once again turned to the field. Our initial investigations had raised many other biologic and geologic questions that we would have to solve to compile a complete picture of the events preceding and following the catastrophe, and we wouldn't be able to find those answers with the evidence we had in the lab.

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Responses

  • caio
    What other animal DNA did they to recreate the extinct Dinosaur?
    9 years ago

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