The Conner has one of the biggest collections of bird skeletons in the nation. Kelly Cassidy opens a drawer and pulls out a box the size of a small microwave oven. It rattles. It contains a disarticulated golden eagle skeleton, each piece labeled with a number (except for the very smallest, which are about the size of a sesame seed).
“Our skeletons are literally boxes of bones,” she says. The Museum has a few dozen skeletons that have been fully assembled, which are useful for public display, but not for research that requires being able to look at the bones from all angles.
The most frequent users of the Conner collection are archaeologists who compare bones they’ve found at a dig with bones in the museum to identify what animals the bones came from.
WSU anthropologist Karen Lupo says the extensive collection of bird and mammal bones at the Conner is essential to her and her students’ ability to do “paleo-environmental reconstructions.” Human archeological sites are often rich with the bones of small animals such as voles and birds. Those species are very sensitive to changes in climate, so their presence in a deposit can say a lot about the local climate and vegetation at the time the animals were alive. But those small animal bones don’t divulge their identity readily. Males can look very different from females, juveniles differ from adults. Many species can only be identified by comparing them with the same parts from known animals of both sexes and different ages of closely-related species.
“If you don’t have a good comparative collection, you can’t do it,” she says. “I think a lot of people don’t understand that; they think you just need one.”
Zach Wilson (’07 M.A.), a graduate student working with Lupo, took a closer look at the site’s faunal elements—the animal bones and teeth–to try to reconstruct the environment the site’s early residents lived in. The assemblage lacked small mammal teeth, which are especially good for determining whether an area was grassland or forest, because the archaeologists who first worked on the site didn’t use a fine enough sieve to catch such tiny pieces. But it was very rich in bison bones.
When one species replaces a close relative during the course of evolution, does it out-compete its relative, or absorb it through inter-breeding? With help from bones in the Conner Museum, Wilson has helped answer that question with regard to the iconic large animal of the North American plains. Wilson studied ancient bones collected at Lind Coulee, an early human site northeast of Pullman. The assemblage was right in bison bones; but what species of bison? Given the time they were deposited, 8,000 to 9,000 years ago, they could have belonged to one of the ancient species of bison that went extinct around that time (Bison occidentalis or Bison antiquus), or to the modern species that replaced them (Bison bison). Wilson took measurements of the ancient bones-horn core diameter, distance between the eye socket and upper jaw, and others-and compared them with the same measurements from modern bison bones in the Conner Museum and from published accounts of bones known to belong to the ancient species. The Lind Coulee bones were intermediate between the modern and the ancient.
“He thinks they might be a cross between Bison occidentalis and Bison bison,” says Lupo. “We know from other studies that [those species] probably overlapped a little bit in time.”
The results are only suggestive; DNA testing would be needed to verify that the bones belonged to hybrid animals. Even so, says Lupo, the finding has sparked discussion in the field—a welcome development, in her view.
“People will start thinking about Pleistocene extinction in a different way. Only 10 years ago we thought that all those animals just ‘went out'”—she snaps her fingers—”and then there were new animals there. Now we’re finding that that’s not always the case.”