کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2193356 1098371 2016 5 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Litter sizes of Daurian ground squirrels peak at intermediate body sizes
موضوعات مرتبط
علوم زیستی و بیوفناوری علوم کشاورزی و بیولوژیک علوم دامی و جانورشناسی
پیش نمایش صفحه اول مقاله
Litter sizes of Daurian ground squirrels peak at intermediate body sizes
چکیده انگلیسی
Litter size and body size of animals may coevolve under the concomitant pressures of sexual selection, fecundity selection, and viability selection. Studies have demonstrated the positive relationship between body size and litter size, consistent with Darwin's fecundity advantage of large body size. However, the counterbalancing selection hypothesis predicts fecundity selection would result in a positive correlation between litter size and body size initially, whereas the opposite pressure by viability selection would decrease litter size with further increasing body size beyond a threshold size. Moreover, the reproduction senescence hypothesis predicts that litter size of old, large females would decline with deteriorating body conditions. In this study, we tested the predictions of the counterbalancing selection hypothesis and the reproduction senescence hypothesis concerning the quadratic relationship between body size and litter size in Daurian ground squirrels (Spermophilus dauricus). Litter size increased initially with increasing carcass weight of females, and then decreased with further increases in carcass weight, supporting the prediction of the counterbalancing hypothesis. However, litter size was not related to body condition index of females, and body conditions improved with increasing body weight, suggesting that the reproduction senescence hypothesis alone cannot explain the observed quadratic relationship between litter size and carcass weight of female S. dauricus.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Mammalian Biology - Zeitschrift für Säugetierkunde - Volume 81, Issue 1, January 2016, Pages 61-65
نویسندگان
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