National Geographic Channel - Waking a Mammoth: Q&A with Scientist Dan Fisher, Part 2

Printed on August 27, 2007 National Geographic Channel

Waking a Mammoth: Q&A with Scientist Dan Fisher, Part 2

April 22, 2009 5:48 PM

NGC: How were the particular research facilities (Jikei University and Saint Petersburg Zoological Institute) chosen?

Dan Fisher: These decisions were all made based on prior collaborative relationships that had been worked out for earlier projects. Dr. Naoki Suzuki of Jikei University had worked with us on two previous mammoth discoveries. The Zoological Institute of the Russian Academy of Sciences is the home institution of Dr. Alexei Tikhonov, one of Russia's premier mammoth researchers and a central member of our collaboration.

NGC: What types of procedures were conducted, and what information was learned at each facility?

Dan Fisher: At Jikei University, the CT scan showed that Lyuba was internally intact, as far as can be resolved using this method. We also saw X-ray-opaque material that we suspected was sediment, in her mouth, throat, part of her trunk and trachea, suggesting she could have died of asphyxiation after falling into mud. In Saint Petersburg, an endoscopic examination allowed visual evaluation of parts of Lyuba's interior and provided some tissue samples. More substantive results, however, came from the investigative surgery, during which we removed one of her milk tusks and the premolars from the left side of her mouth, samples of the sediment in her mouth and throat, samples of intestinal tissue and intestinal contents, and additional tissue samples. These samples are being analyzed in separate laboratories in a number of countries and have provided definitive indications of Lyuba's age, season of death, diet, condition at the time of death and additional aspects of her anatomy and physiology.

NGC: Why is the study of mammoths important? What can they tell us about the ice age?

Dan Fisher: Mammoths were the largest and most widespread of the many animals that went extinct near the end of the last ice age. Determining the cause of their extinction would thus be a big step toward understanding why terrestrial faunas changed so radically at this time. In addition, tusks provide a record of local climate and climate change during the life of each mammoth, making them a valuable source of environmental information. We still have much to learn about climate change and how organisms respond to it, but the primacy of these issues in our own time should make us eager for any new perspective we can gain from earth history.

NGC: What are the scientific "firsts" the team has discovered (or hopes to discover) from Lyuba so far?

Dan Fisher: This is the first time we have been able to do a detailed comparison of a mammoth's tusk and tooth data with soft tissues from the rest of its body, including its intestinal contents. This lets us test how well the tusk and tooth data reflect the overall condition of the animal; the fact that this was successful opens the door to much broader application of the same methods. We also found the first indication of milk residues in a mammoth calf, the first indication of a neck hump in a mammoth calf and the first evidence that this neck fat served a primarily thermoregulatory function.

NGC: Could Lyuba's DNA be used to clone woolly mammoths one day? Can the same techniques potentially be used for cloning other extinct animals?

Dan Fisher: According to Dr. Hendrik Poinar, at McMaster University, in Ontario, Canada, Lyuba's DNA is better preserved than that of any other mammoth analyzed previously. Cloning an extinct animal as complex as a mammoth is far beyond our current technical abilities, but there has been remarkable progress on various aspects of the problem. One day, perhaps. And if for mammoths, then probably also for other extinct animals, but none of this is feasible yet.

NGC: What was the most challenging aspect of the expedition?

Dan Fisher: The most challenging aspect of the expedition was negotiating the variety of perspectives on what should be done with Lyuba, in what order and under what limitations. Complicating resolution of these issues were differences of language, contrasting priorities of different scientists and the philosophical differences between those who wanted to keep Lyuba as close to her original condition as possible and those who were willing to risk some alteration of her condition to extract additional information. It took patience and creativity to find compromise strategies that provided the most information with the least risk to Lyuba's condition.

NGC: Is there anything else you'd like to add?

Dan Fisher: Since the first reports on Lyuba, there was some mystery as to how she could have been so well preserved. This only became more of an issue when we realized that she must have lain exposed beside the Yuribei the whole summer of 2006. An interpretation that finally made sense of this, as well as other aspects of her preservation, was that she had undergone a kind of natural pickling process following her death, and this had, to a degree, prepared her for exposure along the riverbank, without suffering damage from scavengers and bacterial degradation. The idea that this pickling process was an important contributing factor to her preservation is still being tested, but it appears to explain many different aspects of her current condition.

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