a fascination above all others.
I enter the small portable blind, which had been staked down almost two months before and camouflaged with pine branches in order not to disturb the birds. In a few minutes, my equipment is in place: tripod, camera, and an extreme telephoto lens that magnifies approximately twenty-four times and enables detailed images of what would otherwise be indiscernible. Soon, an eagle chick, in a white, downy covering perches on the edge of the nest. The chick has a large head and stubby wings and looks like—a dinosaur. (Many researchers now imagine the young of even the large meat-eating dinosaurs, such as T. rex, to have had downy feathers for insulation.)
Several weeks later, the bird has grown to be nearly as large as an adult eagle. The parents have fed it well. (On one occasion, I photograph it feeding upon half the carcass of a whitetail deer fawn that had been carried into the tree.) A small airplane passes overhead, and the young eagle’s eyes follow it with intense interest, as if thinking, “You can do that?”
Now, with a full set of feathers, the dark brown raptor often faces the wind and flaps its wings, even rising a bit from that platform of sticks in the sky. Then comes the day when it works its way out onto the far end of the branches that support the nest. There, it flaps a bit more, then stands motionless, gazing far outward and beyond. Not quite ready yet to catapult into empty space, an awkward turn-around is executed, and it moves back to the safety of the only world it has ever known. That scene, repeated several times, was reminiscent of a youngster edging out on the diving board at the local swimming pool: hesitating, wondering whether to take that first plunge, wanting it, yet fearing it. The next day, when I came back, the young eagle was nowhere to be seen. The thin air would now be its home for much of its life. The dinosaur had flown. Paleontologists say birds are dinosaurs, and I believe it.
Among the pieces of information contributing to a renewed interest in the prehistoric world are some that we never thought could be obtained, such as the presence of a so-called “medullary” bone layer found in a Tyrannosaurus rex femur that confirms the beast’s gender. Such bone, rich in calcium, is deposited in the skeletons of female birds (more connection) during the egg-laying cycle. So, it seems this rex, (first named “Bob” after Bob Harmon of the Museum of the Rockies, who found it) is really a female. The discovery was described by Mary Schweitzer, Horner, and others, in the journal Science in 2005. In that same year, they detailed still another remarkable find having to do with the same specimen. Following an acid-bath process to dissolve away hard, fossilized bone, some soft tissue remained behind: elastic, vessel-like material with cell-like structures within. This was a first-of-its-kind revelation, and the preservation astonished dinosaur researchers around the world. More work was done on the specimen in 2007, using mass spectrometry to find proteins, and they were found to be most closely linked to—you guessed it—birds. New techniques are leading to new discoveries.
Some phenomena are less subtle and the bones speak quite graphically, which is the case with a unique Triceratops dinosaur pelvis I excavated some years ago. It shows fifty-eight bite-marks made by the teeth of Tyrannosaurus rex. The specimen consists of one of the hip-bones plus the ten fused vertebrae in between the hips called the sacrum. The left hip-bone has had some 15 percent of it bitten off, and the other one is gone completely. Bite-marks of every size and description abound. In a sense, it is fossilized feeding activity of Tyrannosaurus. Based on this fossil, paleontologist Greg Erickson and I described such behavior in The Journal of Vertebrate Paleontology in 1996. The specimen has also been featured in a number of television documentaries, books, and magazines, and Erickson referred to it in a cover article in Scientific American that sought to depict the lifestyle of this largest of dinosaurian carnivores.
One bite-mark shows that a tooth entered at an angle, dragged backwards, making a long groove, then splintered off bone. Numerous other marks are of various depths. A Tyrannosaurus tooth can fit in many of the holes, leaving no doubt about the source. Sometimes, such teeth are compared to steak knives, but that is misleading; the teeth are not narrow, for slicing. Instead, they are round/oval in cross-section, and shaped something like bananas (and the same size!). They are robust and strong, designed for puncturing and tearing off huge hunks of meat and for breaking bone. Erickson further studied the specimen by having a hydraulic press constructed with metal “teeth” and, with it, duplicated such marks in modern bone. It seems that T. rex had a bite-force of at least 3,300 pounds, which is the largest of any known animal and is the equivalent of having the weight of a good-sized passenger car bearing down upon the teeth.
The information that can be gleaned about the behavior and physiology of an extinct creature, even across tens of millions of years, is quite amazing. The bones of the fearfully great reptiles can now speak in ways never previously imagined, something that is at least part of the explanation for why dinosaurs are striding so large across our culture today.
5 / To Be a Naturalist
On Seeing
As long as I live, I’ll hear waterfalls and birds and winds sing. I’ll interpret the rocks, learn the language of flood, storm and the avalanche. I’ll acquaint myself with the glaciers and wild gardens, and get as near as I can to the heart of the world.
John Muir
What does it mean to be a naturalist? Consider this definition: A naturalist is one who studies nature with the intent of greater understanding; who seeks to help or enhance, not harm, the world’s natural processes, and who loves the natural world. So understood, the term can—and I would suggest, should—apply not merely to those who are professional naturalists but in a broad sense, also, to any and every human being.
The science that interests me most is paleontology, and I am drawn also to geology, ecology, and astronomy. In these endeavors, it must be said that I am an amateur. It was not always so, but it is now unusual for an individual to know more than a little about science and also about those things that were known before science came on the scene, because knowledge about our world has so largely become the province of specialists. The scientific approach has produced many results, unlocking aspects of the operations of nature that would never have opened to any other key; modern medicine is an obvious example, and there are numerous others. However, in some arenas, it may not be excessive to say that specialization has been carried to such a length that the situation resembles people down in little grooves, making progress straight ahead, perhaps going a long way in that direction, but the grooves are so deep that they cannot see out of them to all the other grooves. There is the cliché that we “know more and more about less and less.” Not only does the chemist not know what the physicist is doing but the organic chemist can barely talk to the colloid chemist and be understood, or so I’m told, unless they are talking about football and not about their main business.
The result is that we have all these bits and pieces, with few people concerned with connections or with anything like a larger picture, something called a worldview. We have become experts at taking things apart, and this down to smaller and smaller scale, but we are far less adept at putting the pieces back together to produce an integrated frame of reference for the whole. How many courses in business or technology exist for each course in the humanities? Much attention is paid to making a living but much less to making a life. The consequence of having many specialists and almost no generalists is a culture that lacks coherence, one with little in terms of shared outlooks and values and wherein millions struggle with questions of meaning and purpose. Is it possible that amateurs with a broad exposure would have anything to offer here?
The term amateur surely does often signify someone who knows only a little about a subject, who, for example, in the sciences, doesn’t know a proton from a crouton. However, that need not be the case. It can refer, simply, to one who does something else to make a living. In the England of the 1800s, there was little education in the sciences; instead, the great institutions focused upon instructing young gentlemen in the classics: language, literature, and the like. However, natural history was pursued as an avocation by the majority of the English clergy, and there was
