Beldings
Ground Squirrel Population Study
My former graduate student Marissa Lafler and I are collaborating with Dr. Scott Nunes and his current student Jessica Weidenbach at USF combining behavioral data with genetics data from a population just outside Yosemite National Park. Belding's ground squirrel is a social montane rodent that lives in alpine and subalpine meadows in the Sierra Nevadas. The Tioga pass (Mono Co., CA) population has been used for mammalian behavioral studies, but as of yet, no systematic study of the population structure has been conducted. In addition to sampling the squirrels Marissa has analyzed previously collected samples in order to determine both population structure and paternity in multiply sired litters. This information will augment behavioral observations made regarding play between littermates, and provide an understanding of the population genetics of a species important to behavioral studies. She completed her thesis in December, 2011.
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| Belding's ground squirrel being held by Marissa Lafler | Taking an ear clipping for DNA sampling |
Marissa presented a poster on the microsatellite data (Fine Scale Genetic Structure in a Sexually Promiscous Ground Squirrel in the High Sierraat the 2011 Evolution meeting. Here is her abstract:
Spermophilus beldingi (Belding's ground squirrel) is a social montane rodent. The Tioga Pass Meadow (Mono Co. CA) population has been studied behaviorally and demographically for several decades, but little is known about the fine scale genetic structure of the population. Eight microsatellite loci were analyzed via polymerase chain reaction (PCR), offering insight into population health, stochastic events, and dispersal. Genetic structuring by elevation was found, but no sexual structuring was found. These microsatellites were also used to verify maternity and determine paternity. Genetic sibship data was correlated with previously collected behavioral data in an attempt to determine whether play serves to strengthen social bonds, but no significant correlation was found.
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| Dr. Dever working with an undergrad student (Paul Bianchi) | Study site - right outside Yosemite National Forest (east enterance) |
Former undergraduate student Michell Curtin presented a poster at the Bay Area Conservation Symposium held at UC Davis- below is her abstract:
Mitochondrial variation of a Belding's ground squirrel (Spermophilus beldingi) population
Social behavior can impact evolutionary
processes. Therefore, given the opportunity to examine a species exhibiting
high levels of social interaction enables us to understand the connection between
social behavior and genetic structure. In particular, we are interested in Belding's
ground squirrels (Spermophilus beldingi) whose social behavior is distinctly
characterized by nepotism. Although this particular species is not under any
present threat it may be used as model for conservation efforts to understand
other social species at risk of extinction. As part of a preliminary study,
observations of individuals were made for the identification of mothers and
offspring from one population. DNA was then isolated from these individuals
to be used for genetic analyses. Portions of the mitochondrial DNA from the
cytochrome-b gene (cyt-b) and the displacement loop (D-loop) were amplified
using PCR and then sequenced. Approximately 400 base pairs from each region
were examined to assess within-population haplotype diversity.
