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Full-Text Articles in Animal Sciences
Active Facilitation Of Helper Dispersal By Parents And Siblings In The Cooperatively Breeding Acorn Woodpecker, Natasha D. G. Hagemeyer, Walter D. Koenig, Eric L. Walters
Active Facilitation Of Helper Dispersal By Parents And Siblings In The Cooperatively Breeding Acorn Woodpecker, Natasha D. G. Hagemeyer, Walter D. Koenig, Eric L. Walters
Biological Sciences Faculty Publications
Offspring that delay dispersal in cooperatively breeding species have been hypothesized to gain direct fitness benefits via parental facilitation—being passively tolerated on their natal territory by their parents—thereby enjoying enhanced survival and increased probability of acquiring a breeding position in the population. Here we describe active facilitation in the acorn woodpecker (Melanerpes formicivorus) by parents and siblings assisting the dispersal of helpers in their social group. Helpers in this species compete for reproductive opportunities in “power struggles” that take place when all breeders of one sex die or disappear, creating a reproductive vacancy. Individuals compete at power struggles …
Lifetime Inclusive Fitness Effects Of Cooperative Polygamy In The Acorn Woodpecker, Walter D. Koenig, Sahas Barve, Joseph Haydock, Eric L. Walters
Lifetime Inclusive Fitness Effects Of Cooperative Polygamy In The Acorn Woodpecker, Walter D. Koenig, Sahas Barve, Joseph Haydock, Eric L. Walters
Biological Sciences Faculty Publications
Although over 50 y have passed since W. D. Hamilton articulated kin selection and inclusive fitness as evolutionary explanations for altruistic behavior, quantifying inclusive fitness continues to be challenging. Here, using 30 y of data and two alternative methods, we outline an approach to measure lifetime inclusive fitness effects of cooperative polygamy (mate-sharing or cobreeding) in the cooperatively breeding acorn woodpecker Melanerpes formicivorus. For both sexes, the number of offspring (observed direct fitness) declined while the number of young parented by related cobreeders (observed indirect fitness effect) increased with cobreeding coalition size. Combining these two factors, the observed inclusive …
First Report Of Satellite Males During Breeding In Leptodactylus Latrans (Amphibia, Anura), Gabriel Laufer, Noelia Gobel, José M. Mautone, María Galán, Rafael O. De Sá
First Report Of Satellite Males During Breeding In Leptodactylus Latrans (Amphibia, Anura), Gabriel Laufer, Noelia Gobel, José M. Mautone, María Galán, Rafael O. De Sá
Biology Faculty Publications
Individual males can adopt alternative mating tactics. The occurrence of satellite males is a common behaviour across anuran taxa (e.g., Lithobates clamitans, Wells, 1977; Anaxyrus cognatus, Krupa, 1989; Dendropsophus ebraccatus, Miyamoto and Cane, 1980; Rhinella crucifer, Forester and Lynken, 1986). Satellite males take peripheral positions to calling males, and adopt alternate mating tactics in an attempt to intercept females that are attracted to calling males (Wells, 2007) to increase their own mating success. Satellite males could have an inexpensive form of mate-locating, avoiding predators, and saving energy (Arak, 1983). Furthermore, this strategy could play an important role in the genetic …
Female Humpback Whale (Megaptera Novaeangliae) Reproductive Class And Male-Female Interactions During The Breeding Season, Meagan E. Jones
Female Humpback Whale (Megaptera Novaeangliae) Reproductive Class And Male-Female Interactions During The Breeding Season, Meagan E. Jones
Antioch University Dissertations & Theses
This study examined whether female reproductive class (i.e., presence or absence of a calf) in humpback whales (Megaptera novaeangliae) affects female behavior and male-female interactions on the Hawaiian breeding grounds. From 2003-2008, 295 female-calf groups (with or without a male escort) and 256 female no-calf groups (with a male) were observed. Forty-one female no-calf groups were confirmed male-female pairs by genetic sexing or photo-identification. Focal follows of 36 male-female pairs and 50 female-calf groups (29 escorted and 21 unescorted female-calf groups) were analyzed for time budget and movement estimates. Relative fluke size (fluke photogrammetry, n=30) and sighting histories …
Population Ecology Of The Golden Mouse, Robert K. Rose
Population Ecology Of The Golden Mouse, Robert K. Rose
Biological Sciences Faculty Publications
An understanding of the population dynamics of a species requires knowledge of the major life-history parameters of a population, including age at maturity, distribution of age classes, and lifetime reproductive contribution of the sexes, sex ratio, length of the breeding season, mean litter size, rates of growth and survival, and life span. Because few long-term studies have been conducted with Ochrotomys nuttalli as the focal species of investigation, only fragmentary information is available for many population parameters. As importantly, densities of golden mice often are low, making them difficult to evaluate statistically. Little has been published on age at maturity …
The Reproductive Cycle Of Microtus Ochrogaster In Eastern Kansas, Robert K. Rose, Michael S. Gaines
The Reproductive Cycle Of Microtus Ochrogaster In Eastern Kansas, Robert K. Rose, Michael S. Gaines
Biological Sciences Faculty Publications
About 800 Microtus ochrogaster were live—trapped at biweekly intervals from May 1971 through March 1973 in 3 grassland study areas in eastern Kansas, USA. Details of reproduction were determined by autopsy. Population density increased through the first winter, reached a peak in April 1972, then declined sharply during that summer and beyond. Body length, but not body mass, tended to be positively related to density. Both sexes matured at about the same weight; development was somewhat prolonged during the winter months, especially in the winter preceding the population peak. Pregnancy rates were high, approaching maximal iteroparity, throughout the study, with …
Population Dynamics Of Microtus Ochrogaster In Eastern Kansas, Michael S. Gaines, Robert K. Rose
Population Dynamics Of Microtus Ochrogaster In Eastern Kansas, Michael S. Gaines, Robert K. Rose
Biological Sciences Faculty Publications
Four eastern Kansas populations of the prairie vole, Microtus ochrogaster were live trapped from 1970—73 to gain insight into the population regulation of this species. All four populations exhibited a 2—yr cycle in numbers with peak densities generally occurring in June 1972. Peak densities were followed by a decline in numbers, a recovery, and a population crash in spring 1973. Reproductive parameters changed dramatically as density rose and fell. The summer breeding season in the crash year of 1973 was shortened by at least 3 mo. A reduction in breeding activity occurred during the summer of every year of the …