Age of primiparity and implications of early reproduction on life history in female Columbian ground squirrels
نویسندگان
چکیده
منابع مشابه
Senescence and age-related reproduction of female Columbian ground squirrels
1. Three hypotheses have been proposed to explain age-structured patterns of reproductive investment and somatic investment: residual reproductive value, senescence and evolutionary restraint. We evaluated these hypotheses for female Columbian ground squirrels ( Spermophilus columbianus ) by examining age-related patterns of somatic and reproductive investment. Females were designated as succes...
متن کاملEctoparasites and fitness of female Columbian ground squirrels.
Parasites play an important role in the evolution of host traits via natural selection, coevolution and sexually selected ornaments used in mate choice. These evolutionary scenarios assume fitness costs for hosts. To test this assumption, we conducted an ectoparasite removal experiment in free-living Columbian ground squirrels (Urocittelus columbianus) in four populations over three years. Adul...
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Reproductive success of females in iteroparous species usually increases early in life, then remains constant or declines. The restraint hypothesis suggests that primiparous females limit their 1st reproduction in order to avoid future costs to survival, reproduction, or both, whereas constraint indicates that primiparous females are limited in their 1st reproductive attempt either because they...
متن کاملFitness implications of seasonal climate variation in Columbian ground squirrels
The influence of climate change on the fitness of wild populations is often studied in the context of the spring onset of the reproductive season. This focus is relevant for climate influences on reproductive success, but neglects other fitness-relevant periods (e.g., autumn preparation for overwintering). We examined variation in climate variables (temperature, rainfall, snowfall, and snowpack...
متن کاملon translation of politeness strategies in dialogues involving female characters in translations and retranslations of novels translated before and after the islamic revolution of iran and their effects on the image of women: a polysystem theory approach
abstract reception environment has considerable effects on accepting a translation. as the expectations of a target culture and its values and needs change throughout history, its criteria for accepting a translation or rejecting it will change accordingly (gentzler, 2001). the expectations of iran, as the reception environment in the present study, have changed after the islamic revolution. i...
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ژورنال
عنوان ژورنال: Journal of Animal Ecology
سال: 2004
ISSN: 0021-8790,1365-2656
DOI: 10.1111/j.1365-2656.2004.00793.x