Oklahoma's number one blog for natural and cultural history.
Today begins an eleven-week blogging journey, a journey unlike anything you’ve ever seen. Stick with us, and we’ll take you behind the scenes for a first-hand look at the best of the best from each of our eleven collections. Curators and collection managers carefully chose the most significant and/or unique item from their collection, and one by one, we will reveal them to you. We hope you’re ready, because it’s going to be one exciting, international, world-record-breaking journey. Welcome to “Inside the Treasure Box”.
We’ve decided to kick off our new series with one of the rarest mammals in North America, straight from our mammalogy department. The black-footed ferret is an endangered species and was declared extinct in the wild in 1979 and again in 1986. However, the recovery of the species from a few individuals, that were discovered by chance thanks to a Wyoming rancher’s dog, resulted in successful captive breeding populations and reintroductions and recovery in several states.
"Historically, black-footed ferrets were found throughout the Great Plains, including Oklahoma, from Canada to northern Mexico," said Janet Braun, mammalogy staff curator. "Secretive and active only at night, they are extremely dependent on prairie dogs, both for food and burrows. Significant decrease in prairie dog colonies, conversion of grasslands to agriculture and disease contributed to the extinction of this species."
A close-up of the black feet for which the species is named
Today there are more than 1,000 individuals living in the wild in South Dakota, Wyoming, and Arizona. Only 5 specimens are known from Oklahoma, and as it is now extirpated (meaning it has disappeared from the area) in the state, this specimen is one of Oklahoma’s most rare mammal specimens in collections. This specimen was collected July 25, 1928 just one mile east of Norman.
Be sure to stay tuned for week two’s “big” reveal by following our blog and connecting with us on social media. By big, we mean one of the biggest in the world. You won’t want to miss this. What’s that, you say? You’re on the edge of your seat? Well, we’re not usually into making deals, but if blog receives 1,000 visits OR receives 10 new followers by Friday, Sept. 20 at 3 p.m., we may just be inclined to release a teaser. A “big” teaser.
In 2005, a mother and two baby rats were discovered in Salt Lake City onboard a truckload of sterile medical supplies shipped from China. The mother was destroyed, but the babies were kept. The rats were sent to Dr. Michael Mares, the Sam Noble Museum’s Director and a noted mammalogist, for identification. However, a rather puzzling DNA analysis was conducted at Oklahoma State University. Although the mother looked like a common ship rat, DNA suggested she was not a pure ship rat. Dr. Mares teamed up with genetics graduate student Dr. Justin Lack of Oklahoma State University in a pursuit that would eventually yield novel discoveries for invasion biology.
“In our efforts to learn more about Rattus in the United States, the project eventually grew into Lack’s dissertation, which is a fine piece of work involving both the ship rat and the Norway rat, two of the most destructive invaders in the world,” recalls Dr. Mares.
Along with Dr. Ron Van Den Bussche and Dr. Meredith Hamilton of OSU and Dr. Janet Braun of the Sam Noble Museum, they began researching the invasion history of various Rattus species using population genetics, a method of research in which the geographic patterns of genetic diversity are analyzed to understand gene flow and evolutionary history. During the study, the group encountered a third species, Rattus tanezumi, capable of hybridizing with the ship rat (Rattus rattus). For photographs of these species, click here.
Although a population of Rattus tanezumi had been described from California, Dr. Lack and his colleagues were the first to report the second and only other known population in Florida. This discovery suggests Rattus tanezumi likely invaded the United States twice, once on each coast. Globalization in means of transport (ships, trucks and planes) enabled the hybridization. Unlike the hybridization of various dog breeds, which are considered to be the same species, Rattus tanezumi contains genomic material from Rattus rattus (a separate species) and may become genetically swamped by the more widespread and aggressive species.
“Genomic swamping like this is very rare in mammals, making this a really cool result,” said Dr. Lack. “However, a major consequence has been the potential loss of the R. tanezumi nuclear genome.”
To better understand the invasion origins of the Norway and ship rat, Dr. Lack and his colleagues conducted a second study that provided insight into dispersal patterns. They found that the Norway rat invaded from at least four sources, most likely two from Asia and two from Europe and/or Africa, whereas the ship rat appears to have entered the United States in a single wave of invasion, with subsequent invasions only occurring in southeastern Florida but never moving inland.
Their work showed that the Norway rat, Rattus norvegicus, continues to move throughout the United States, whereas the ship rat, Rattus rattus, no longer continues to disperse or enter. Analyses suggest that competition with the more aggressive Norway rat may limit the success of the ship rat. Through this study, researchers gained insight into how these species disperse and repopulate outside species lines. They are two of the principal pest species in the United States and can have great adverse effects on human health by acting as reservoirs and dispersers for a variety of diseases, from bubonic plague to typhus and leptospirosis. This work on dispersal patterns can be useful in limiting the spread of the rat-borne pathogens.