February 2011
USGS bird curator with bird specimens housed at the Smithsonian Museum of Natural History (photo: Kara Capelli, USGS).
Framed by row upon row of floor to ceiling white boxes, Claudia Angle is holding a tray of carefully prepared birds.
Prepared as museum specimens, that is.
Behind her are several other trays of bones, eggs, and colorful feathered skins. At home in this land of shelves, skins, feathers, and bones, Angle, a United States Geological Survey (USGS) taxonomist, points to a few of the birds. “That one’s a now-extinct passenger pigeon. And that’s an ivory-billed woodpecker. And see that?” She points to a ruffed grouse. “Teddy Roosevelt donated that one. You can see his signature here on the tag.”
Angle is one of 13 USGS taxonomists working with collections at the Smithsonian Museum of Natural History. As a part of the Biological Survey Unit, Angle works as the USGS collections manager for birds.
In conjunction with the Smithsonian National Museum of Natural History, the USGS scientists have responsibility for managing the collections of North American birds, mammals, and amphibians and reptiles, totaling more than a million specimens and growing. They’ve been a part of the U.S. government’s taxonomic research program since the late 1800s when they started the bird and mammal collections at the national museum. Each collection represents part of the documentation process of identifying individual organisms on a universal scale, a vital part of the cumulative taxonomic process that enables scientific research.
Despite their different sources of funding, the USGS and Smithsonian collections staff works as a cohesive team. “If you watched us on the job you wouldn’t be able to tell who works for whom, except possibly by my USGS lanyard,” says Bob Reynolds, the chief of the USGS Biological Survey Unit.
USGS curator with bat specimens (photo: Kara Capelli, USGS).
“We’re staff on the same mission – caretakers of permanently preserved dead animals in the service of science and knowledge. The accumulation of specimens and associated biological data over time makes this historical record so valuable.”
Through time, he said, the collections become an increasingly priceless chronicle of biological survey data, recording extinctions, range extensions or changes, species relationships, the effects of climate change, and a host of other information. The USGS Biological Survey Unit has been acquiring specimens and their associated data, as well as conducting research on the collections since 1889 when an agreement was reached for the deposition within the Smithsonian Institution of specimens acquired in the course of Biological Survey activities.
Each specimen tells an important story. It may be a story that is already written, as in the case of the now-extinct passenger pigeon -- or it may be a story that is being written now -- as in amphibian or bird collections shedding light on how climate change is affecting the geographic range of a species. Or it may be a story that has not yet been conceived, but whose raw material – in the form of specimens – is housed for some future scientist to mine.
“Most people get paid and funded on the basis of an end product, whereas we maintain these collections just in case someone needs them some day – it could be tomorrow or it could be a century from now,” said Suzy Peurach, the USGS mammalogy collections manager.
Still, she concedes that it is nice to see one’s work pay off in the here and now. “Once I was documenting and collecting mice from the southwestern U.S. It seemed almost pointless to collect all of those specimens at the time, but when the serious hantavirus broke out scientists were able to look at the specimens we’d collected and track the spread of the virus through the mice.”
Likewise, many discoveries based on the collections are made years after the specimen has been archived, using technologies that weren’t available at the time the specimen was initially collected. According to Angle, “At one point, there was a limited number of taxonomists asking for and using our specimens, and traditional taxonomists were retiring and not being replaced by young scientists. We were worried about what would happen to the collections because it seemed as though fewer and fewer taxonomists were available to study the specimens. Enter the new DNA technologies and boom! New generations of scientists trained in molecular genetics are increasingly using our specimens, and these collections are more valuable than ever.”
Left: Bob Reynolds, USGS lead for Smithsonian collections, with a field notebook that documents the collection of biological specimens. Right: Extinct species, like these passenger pigeons, only exist in natural history collections (photo: Kara Capelli, USGS).
These new genetic technologies also help USGS scientists know exactly what specimen they are dealing with -- which is much harder than it might seem.
“I could show you a series of 25 frogs, identical to the untrained eye – but if you look at their genetic makeup, they are completely different species,” said Reynolds.
Other species, though, may look different on the outside but genetically are the same species. As USGS mammalogist Suzy Peurach pointed out, “I have a tray of squirrels that are all different colors – black, brown, white, and even a dark red. They look almost completely different, but genetically they are almost identical.”
This fairly new ability to use genetic tools to precisely identify genetic relationships is hugely important, Reynolds said. Genetic diversity, he noted, is the most fundamental level of biodiversity, providing the raw material for evolutionary processes to act upon and affording populations the opportunity to adapt to their surroundings.
The collections are also valuable in documenting range extensions or shrinkage because of habitat alteration, climate change, or other factors.
“More than 50 years ago,” said Angle, “it was a big deal when we received a mockingbird specimen from the D.C. area because it was considered too far north to be in their habitat range. Now, there are mockingbirds all over.”
Likewise, the data housed in the form of dead animals in trays or jars are also important in restoration research because before you can restore a habitat you must know what used to be in it. In many cases, that type of quantitative data doesn’t exist anywhere except in museum collections.
“For instance,” said Reynolds, “if we didn’t know what grizzly bears used to eat, restoration efforts would not be as effective. However, using these collections, we can sample a specimen of grizzly bear from more than a 100 years old and determine that then, before any major threats to their population arose, grizzlies from a particular region primarily ate salmon. From there, we could create a better-informed restoration plan.”
Each North American vertebrate (animals with a backbone) specimen that comes into the museum is carefully documented by the USGS taxonomists and their staff -- where and when it was found, its genus and species or subspecies, and any other possibly relevant information. Each individual specimen is assigned a unique sequential museum number and the specimen and associated data are cataloged into the collections of the National Museum. This catalog information becomes part of the museum’s computer database, which is available online to anyone seeking information about the collections.
“This helps makes our collections accessible to scientists all over the world,” Reynolds said. “In the United States and Europe, most species of vertebrates are fairly well documented, but the same isn’t true for other countries. We’re working with countries around the world to collect and share specimens, but we’ve got plenty of work ahead of us.”
One thing is for certain – the USGS-Smithsonian collections can never be complete. By some estimates only 6 percent of the world’s species have been discovered and formally described by scientists – less than 2 million of the 30 million estimated to exist. Many of these, said Reynolds, will very likely go extinct before we ever even knew they existed.
“Some people think that there’s nothing left for scientists to figure out, which is just not true,” said Reynolds. “In fact, each discovery we make leads to more and more questions that emphasize how little we know. There just aren’t enough scientists to do all the research we need.”
For example, said Reynolds, there are millions of undocumented insects, but worldwide there are only a handful of entomologists working as taxonomists.
