The scans provide three-dimensional views of the woodpecker’s skull, which will allow scientists to learn more about the little-seen bird. As Dr. Timothy Rowe, the lab’s director, pointed out, “We know more about Tyrannosaurus rex than we do the ivory-billed woodpecker.” The images are available at the DigiMorph Web site. They include three-dimensional images of the bird’s skull cavity, which can be viewed from any angle and a reconstructed exterior view of the bird’s head. The user can view each image in three dimensions, rotate it, watch animations from the scan itself, slice it open and look at it from the inside out and otherwise manipulate the data to gather information. The images can tell scientists the bird’s capacity for smell and taste, what it might eat and where it might live. For example, the specimen’s olfactory cavity seems to be relatively large, meaning that the ivory-billed woodpecker depends a great deal on its sense of smell to find food. Models of the skull can be made from the images, giving scientists a hands-on feel for the bird. Researchers from the Cornell Lab of Ornithology announced that the woodpecker had been seen at least seven times in the Cache River National Wildlife Refuge Preserve in Arkansas. It was caught on a few seconds of videotape. The news created a stir in the birding community and beyond. There had been no confirmed sightings of the bird, distinguished by its long, white bill, for more than 60 years. The bird was on the CT Lab’s list of items to scan; with the announcement it moved to the front of the line. It just so happened that a student who works in the CT Lab was at Cornell University, so she hopped a flight with the stuffed specimen from the ornithological center’s holdings. Rowe describes the specimen as “a bit moth-eaten and weathered.” But it provides hints of why it has been called the “lord God bird.” The specimen has its red and black feathers, its imperial eyes (although they are glass in the specimen) and predatory bill.
That the specimen ended up at Cornell is its own bit of luck. It was found, not in the wild, but on eBay. It’s against the law to sell stuffed specimens of extinct or endangered animals, so it was confiscated by the U.S. Department of Fish and Wildlife and transferred to Cornell. The specimen is one of few around the country and little damage had been done to the skull in the taxidermy process. The lab’s scanner, while similar to medical-imaging scanners used in hospitals, is much more powerful and can make very fine images of the smallest objects. Working on the same principles as medical CAT scan devices, the High-Resolution X-ray Computed Tomography facility, known by scientists worldwide as UTCT, literally photographs “slices” —or cross-sections—of fossil matter so that researchers can better understand the characteristics and capabilities of long-extinct animals. The UTCT has scanned more than 3,000 items, about half of which are biological specimens. The scans contribute to a number of National Science Foundation research initiatives into amphibians, mammals, birds and fish.
In addition to its biological and paleontological uses, the UTCT has scanned a Martian meteorite from NASA, a 16th-century liturgical hymnal and sculptural antiquities that are broken and in need of repair — repair made easier by knowledge gained at UTCT. Another object scanned recently was a rock about the size of a Bic lighter. Inside the rock was a 350-million-year-old fossil of a tetrapod—the lizard-like creature thought to be one of the first to make the transition from water to land. The 3-D image made by the scanner showed the complete fossil, about eight centimeters long, in all its detail. The fossil was sent by a scientist in Norway. Other samples come from around the world. A piece of rock core drilled from the bottom of the Gulf of Mexico was another object that has been scanned. The rock is honeycombed with tiny tunnels. “They are trying to figure out if the worms make the holes or if the worms are crawling through holes that are already there,” said Julian Humphries, assistant director of the lab. The lab is a multi-user facility funded by the National Science Foundation. The free site, DigiMorph.org, presents the images of more than 300 vertebrates and many invertebrates that were scanned with a high-resolution computer tomographic machine. The subjects range from rare seeds to fossils to tadpoles to hummingbirds. Photos of ivory-billed woodpecker courtesy UTCT Related Sites
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