Ultrasonic vocalization in prairie voles (Microtus ochrogaster) : evidence for begging behavior in infant mammals?

UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
Brian N. Lea (Creator)
Institution
The University of North Carolina Wilmington (UNCW )
Web Site: http://library.uncw.edu/
Advisor
Kim Sawrey

Abstract: This research examines ultrasonic vocalization (USV) emission by infant prairie voles (Microtus ochrogaster). Rodent pups of many species emit USVs (Anderson, 1954), commonly in response to stressors such as isolation and hypothermic conditions (Allin & Banks, 1971; Oswalt & Meier, 1975). Much research has been conducted to examine the use of these ultrasounds as the basis of a communication system between offspring and parents (Zippelius & Schleidt, 1956), and the malleability of USV production by infant rodents (Bell, et al., 1972; Blake, 1992) suggests high susceptibility of ultrasounds to ontogenetic selection. USV production by prairie voles has been compared to a sympatric species, the montane vole (Microtus montanus), in several studies (Blake, 2002; Rabon, et al., 2001; Shapiro & Insel, 1990) and prairie voles have been found to produce ultrasounds at a higher rate, a finding which has been attributed to the different mating systems of the two species. Prairie voles exhibit a monogamous mating system, biparental care of pups, tenacious nipple attachment by pups, and litter overlap, all contributing to sibling competition among the young of this species (Gilbert (1995). In contrast, montane voles mate polygynously, only the dam cares for the pups, and there is no tenacious nipple attachment or litter overlap, suggesting reduced sibling competition. In the current study, data indicate that prairie voles show no differences in ultrasound production by the heaviest and lightest pups in a small litter. However, in large litters, where pup number may exceed the number of functional nipples the dam provides, the lightest pup produces USVs at a much higher rate than the heaviest pup. It is suggested that this difference is reflective of the relatively large difference in deprivation level in large litters between the pups at the two weight extremes. This finding is related to the avian begging literature, which also includes some examples of mammalian begging. It is hypothesized that prairie voles may beg by using ultrasounds as an honest signal of need to the dam and then by engaging in a scramble competition with littermates for access to nipples when the dam nurses.

Additional Information

Publication
Thesis
A Thesis Submitted to the University North Carolina Wilmington in Partial Fulfillment Of the Requirements for the Degree of Master of Arts
Language: English
Date: 2009
Keywords
Animal behavior, Animal communication, Prairie vole, Ultrasonics in biology, Voles--Research
Subjects
Ultrasonics in biology
Prairie vole
Animal communication
Animal behavior
Voles -- Research