Fairbanks Museum Collection Contributes to International Research
An article published in Biology Letters on April 26, 2023 adds to our understanding of Bahamian hutia (Geocapromys ingrahami), a large rodent that lives on The Bahamas Archipelago. A team of researchers from Middlebury College, Florida Museum of Natural History, and the University of Nevada, Reno collaborated with Beau Harris, director of collections at the Fairbanks Museum, to use historic DNA from a taxidermy mount to trace the geographic range and diversity of this species.
Alexis Mychajliw, an assistant professor at Middlebury College and a Caribbean mammal expert, visited the Fairbanks Museum with students and happened to spot the Bahamian hutia mount that was labeled as such but referred to as a “hamster” in the specimen’s old paperwork. Absolutely shocked at the discovery, Mychajliw, with permission from Harris, contacted her close colleagues Oswald and LeFebvre, who also study hutias, about the possibility of sequencing the DNA of the specimen. The team was excited to unravel the mystery regarding how this tropical specimen managed to get to Vermont and to understand where it belongs in the rodent family tree. Importantly, this specimen could provide critical new information regarding the genetic diversity of the species through time.
Harris provided access to the hutia mount and helped determine where a small sample could be taken for DNA sequencing. He said, “We ultimately decided on the already damaged tail.” He also provided some of the basic documentation for the specimen, identifying the collector, D.P. Ingraham, and year of acquisition, 1891. “After the sample was analyzed and DNA was sequenced, I dug deeper into the Fairbanks Museum records and discovered several letters from the D.P. Ingraham. I also corresponded with the American Museum of Natural History in New York where individuals from the same collecting event by Ingraham are housed today.”
The research into correspondence with D.P. Ingraham recovered 18 letters that describe the hutia he collected, including the location – a tiny island in the southern Bahamas where the last “native” population of Bahamian hutias live today. The specimen that found its way to the Fairbanks Museum is the only one from a set of 15 to be separated from the group: the American Museum of Natural History received the other 14. Correspondence between Ingraham and the Fairbanks Museum indicates he “held one of them out and sold it to the Fairbanks Museum.” Harris explains collections in small and medium-sized museums are “sometimes referred to as ‘dark’ collections because they’re not generally thought of as scientifically significant or don’t have the traditional data associated with them.”
Mychajliw, Oswald, and LeFebvre have long sought to unravel the genetic diversity loss of Bahamian hutia across the past 10,000 or so years. The species has been on a rapid decline in distribution size and genetic diversity since European colonization in the region at the end of the fifteenth century. “Nearly half of all known hutia species went extinct following human arrival, and the Bahamian hutia is now one of the 11 hutia species.” Co-authors Oswald and LeFebvre previously used ancient DNA that spans from thousands of years old to 500 years old to understand the diversity loss in Bahamian hutia through time. However there is a gap in our knowledge regarding genetic diversity of this species between 500 years ago and the most recently DNA sequenced individuals from from the 1960s. The genomic data collected from the Museum’s taxidermy mount allowed the research team to gauge genetic diversity change and the impact of human activities on the Bahamian hutia in the late 1800s.
Oswald extracted DNA in a lab dedicated to “ancient” specimens and after processing the sample sent it for sequencing. The genetic data from the Fairbanks specimen allowed the research team to them to place it in the context of populations living and extinct in across the islands today based on mitochondrial sequence data. The research revealed that the specimen in the Fairbanks Museum was part of the last remaining natural Bahamian hutia population. The authors found that the Fairbanks specimen is part of the southern Bahamian hutia population, which is now largely restricted to East Plana Cay. The results indicate that from a genetic perspective populations alive today are nearly genetically identical to ones from 1891 and ones 500 years ago. This important information for conservation as it provides benchmarks of genetic diversity through time. This study importantly also highlights how ‘dark’ museum specimens inform new conservation-relevant understandings of diversity.” The research suggests that “in the absence of human pressures, introduction of non-native species, or annihilation from catastrophic storm events, an isolated population could maintain steady diversity for at least 500 years.”
This discovery underscores the potential for natural history collections to contribute to ongoing scientific research. The use of natural history collections can “uncover the complex evolutionary consequences of human pressures and generate baselines for interpreting magnitudes of species loss or persistence relevant to conservation.” In this case, the Bahamian hutia specimen at the Fairbanks Museum was part of the original museum collection, purchased by Franklin Fairbanks in 1891 and mounted by William Balch. “This research is just another way the Fairbanks Museum remains relevant and connected. Our natural history collections tell an important story, and we’re delighted to be part of this research,” says Adam Kane, executive director of the Fairbanks Museum.