Download or read book Body Lipids Reproduction and Hibernation in the Golden mantled Ground Squirrel Spermophilus Lateralis written by Nancy Gene Forger and published by . This book was released on 1986 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Sleep and Hibernation in the Golden mantled Ground Squirrel Spermophilus Lateralis written by Jennie Elizabeth Larkin and published by . This book was released on 1996 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effect of Photoperiod on Torpor and Weight Cycles in the Golden Mantled Ground Squirrel Spermophilus Lateralis written by Kelly Lynn Stadille Manley and published by . This book was released on 1982 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Altidudinal Variation in the Annual Cycle and Life History of the Golden mantled Ground Squirrel Spermophilus Lateralis written by Michael Tyken Bronson and published by . This book was released on 1977 with total page 296 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Reproductive Ecology of Female Golden mantled Ground Squirrels written by Caitlin Pratt Wells and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding the life-history decisions of female vertebrates is critical to predicting individual- and population-level processes such as individual fitness, genetic diversity, population dynamics, and the evolution of sociality. In mammals, female-biased philopatry generates the potential for cooperation and conflict among female kin who remain in their natal range, and these relationships are likely to affect life-history decisions such as when and how femals reproduce. Yet despite abundant research into the role of kinship in the reproductive ecology of social mammals, we have little understanding of its role in solitary species, such as the small-bodied ground squirrels. This dissertation consists of four studies that investigate the reproductive ecology of female golden-mantled ground squirrels (Callospermophilus lateralis), paying particular attention to the effects of social and environmental factors on age of first reproduction, drivers of multiple paternity, and allocation of offspring sex. For hibernating squirrels, the amount of energy stored as fat may influence several components of female fitness, including timing of first reproduction, reproductive success, and offspring sex allocation, but fat stores are difficult to quantify in living animals. In chapter one, I use a non-destructive method to characterize body composition (lean mass versus fat mass) and condition (fat stores) of adult females at multiple stages in the circannual cycle. Body mass explained a high proportion of the variation in fat mass during the emergence and pre-hibernation stages, but less during the reproduction stage. Additionally, I found a strong effect of mass even after accounting for variation among individuals and years. These results suggest that body mass is a good estimate of body condition during the periods of emergence and pre-hibernation fattening, and therefore may be useful to predict important components of fitness such as female reproductive success and overwinter survival. Selection for early reproduction should be strong when lifespans are short, because early-maturing individuals are more likely to successfully reproduce before they die, yet females often delay reproduction beyond what appears to be optimal. In chapter two, I use 21 years of demographic data from a free-living population of golden-mantled ground squirrels to evaluate the developmental and social factors that may constrain early reproduction in this short-lived, asocial species. I found that females who would reproduce as yearlings were weaned earlier in the summer than females who waited until age 2 to reproduce, and that early weaning was associated with higher growth rate during the natal summer. Females were more likely to reproduce as yearlings when there were more adult males present, possibly because exposure to males accelerates reproductive maturity or due to the increased likelihood of conception with more male mates. Maternal presence had no facilitating or inhibitory effect on yearling reproduction, but yearlings with a littermate sister present were only 22% as likely to reproduce as females without a sister present. Competition among siblings before or after weaning may reduce growth rates in female rodents, and if golden-mantled ground squirrel sisters remain in close proximity in their natal range, developmental delays may extend to delays in reproductive maturation. Female mammals often mate with multiple males, resulting in multiple paternity within their litters. While rates of multiple paternity appear quite stable in some species, other species show substantial variation among populations or among years within populations. In chapter three I use 18 years of genetic and demographic data to examine the mating system and patterns of multiple paternity in a free-living population of golden-mantled ground squirrels. The mating system was polygynandrous, but opportunity for sexual selection was lower for females than for males. Annual reproductive success of males was low for yearlings and new immigrants, and increased with breeding tenure in the population. Multiple paternity was evident in 62% of litters. I found little support for the null model of multiple paternity, but in accordance with the socioecological model of male monopolization, rates of multiple paternity decreased with female spatial clustering, unless male-male competition, as indicated by male density, was also high. From Bateman gradients, I found no fitness benefit of multiple paternity for females, and in support of the female choice model, multiple paternity decreased with maternal age and peri-oestrous mass. Together, these results suggest that variation in the rate of multiple paternity in golden-mantled ground squirrels was determined primarily by the active strategies of males and females. High rates of multiple paternity in high-density years may increase genetic diversity during population peaks, particularly in years when more yearling females reproduce. Evolutionary theory predicts that parents should bias investment in offspring toward the sex that will yield the higher fitness returns, and one outcome may be biased offspring sex ratios. In chapter four, I use 18 years of pedigree and demographic data to investigate variation in offspring sex ratios in a free-living population of golden-mantled ground squirrels. Despite overall parity in offspring sex ratio, I found predictable changes in offspring sex ratio in response to female density at the population level: squirrels produced more daughters when female density was low, and more sons when female density was high. At the individual level, females adjusted litter sex ratios similarly, but only in response to high densities of kin, and not in response to density of nonkin. This effect was reversed for older females (>̲3 years) in dense kin neighbourhoods, who were more likely to produce daughters, perhaps because older females had the behavioural dominance necessary to recruit daughters at high densities. By contrast, litter sex ratios did not vary with adult sex ratios, maternal condition, or food availability. These results support the local resource competition theory of offspring sex allocation for this species, and are consistent with socially-induced physiological mechanisms that bias offspring sex in ground squirrels. Knowledge of female relatedness revealed patterns of sex ratio adjustment that otherwise would have been obscured, highlighting the importance of interactions with kin in an asocial species.
Download or read book Effects of Hibernation on Gene Expression in Skeletal Muscles of the Golden mantled Ground Squirrel Spermophilus Lateralis written by Youlin Li and published by . This book was released on 1994 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of the Herbal Formula on the Body Weight During the Summer Activity and Hibernation Stages in the Golden mantled Ground Squirrel Spermophilus Lateralis written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Comparative Ecological Physiology of the Golden mantled Ground Squirrel Citellus Lateralis written by John Andrew Phillips and published by . This book was released on 1979 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book EFFECTS OF GENDER AND HIBERNATION ON LIVER AND SPLEEN WEIGHTS IN THE GOLDEN MANTLED GROUND SQUIRREL SPERMOPHILUS LATERALIS written by and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Wildlife Review written by and published by . This book was released on 1988 with total page 502 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Canadian Journal of Zoology written by and published by . This book was released on 1999 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecosystem Dynamics of the Boreal Forest The Kluane Project written by Vancouver Charles J. Krebs Professor of Zoology University of British Columbia and published by Oxford University Press, USA. This book was released on 2001-03-31 with total page 542 pages. Available in PDF, EPUB and Kindle. Book excerpt: The boreal forest is one of the world's great ecosystems, stretching across North America and Eurasia in an unbroken band and containing about 25% of the world's closed canopy forests. The Kluane Boreal Forest Ecosystem Project was a 10-year study by nine of Canada's leading ecologists to unravel the impact of the snowshoe hare cycle on the plants and the other vertebrate species in the boreal forest. In much of the boreal forest, the snowshoe hare acts as a keystone herbivore, fluctuating in 9-10 year cycles, and dragging along secondary cycles in predators such as lynx and great-horned owls. By manipulating the ecosystem on a large scale from the bottom via fertilizer additions and from the top by predator exclosures, they have traced the plant-herbivore relationships and the predator-prey relationships in this ecosystem to try to answer the question of what drives small mammal population cycles. This study is unique in being large scale and experimental on a relatively simple ecosystem, with the overall goal of defining what determines community structure in the boreal forest. Ecosystem Dynamics of the Boreal Forest: The Kluane Project summarizes these findings, weaving new discoveries of the role of herbivores-turned-predators, compensatory plant growth, and predators-eating-predators with an ecological story rich in details and clear in its findings of a community where predation plays a key role in determining the fate of individuals and populations. The study of the Kluane boreal forest raises key questions about the scale of conservation required for boreal forest communities and the many mammals and birds that live there.
Download or read book Some Effects of Food Consumption on the Hibernation Behaviour and Body Weight of the Golden mantled Ground Squirrel Citellus Lateralis written by Douglas S. Barnes and published by . This book was released on 1970 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Behavior of Golden mantled Ground Squirrels Citellus Lateralis Following Periodic Arousal from Hibernation written by Kenneth G. Torke and published by . This book was released on 1972 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Ecological Physiology of Daily Torpor and Hibernation written by Fritz Geiser and published by Springer Nature. This book was released on 2021-08-23 with total page 326 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides an in-depth overview on the functional ecology of daily torpor and hibernation in endothermic mammals and birds. The reader is well introduced to the physiology and thermal energetics of endothermy and underlying different types of torpor. Furthermore, evolution of endothermy as well as reproduction and survival strategies of heterothermic animals in a changing environment are discussed. Endothermic mammals and birds can use internal heat production fueled by ingested food to maintain a high body temperature. As food in the wild is not always available, many birds and mammals periodically abandon energetically costly homeothermic thermoregulation and enter an energy-conserving state of torpor, which is the topic of this book. Daily torpor and hibernation (multiday torpor) in these heterothermic endotherms are the most effective means for energy conservation available to endotherms and are characterized by pronounced temporal and controlled reductions in body temperature, energy expenditure, water loss, and other physiological functions. Hibernators express multiday torpor predominately throughout winter, which substantially enhances winter survival. In contrast, daily heterotherms use daily torpor lasting for several hours usually during the rest phase, some throughout the year. Although torpor is still widely considered to be a specific adaptation of a few cold-climate species, it is used by many animals from all climate zones, including the tropics, and is highly diverse with about 25-50% of all mammals, but fewer birds, estimated to use it. While energy conservation during adverse conditions is an important function of torpor, it is also employed to permit or facilitate energy-demanding processes such as reproduction and growth, especially when food supply is limited. Even migrating birds enter torpor to conserve energy for the next stage of migration, whereas bats may use it to deal with heat. Even though many heterothermic species will be challenged by anthropogenic influences such as habitat destruction, introduced species, novel pathogens and specifically global warming, not all are likely to be affected in the same way. In fact it appears that opportunistic heterotherms because of their highly flexible energy requirements, ability to limit foraging and reduce the risk of predation, and often pronounced longevity, may be better equipped to deal with anthropogenic challenges than homeotherms. In contrast strongly seasonal hibernators, especially those restricted to mountain tops, and those that have to deal with new diseases that are difficult to combat at low body temperatures, are likely to be adversely affected. This book addresses researchers and advanced students in Zoology, Ecology and Veterinary Sciences.
Download or read book Journal of Mammalogy written by and published by . This book was released on 1999 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Living in a Seasonal World written by Thomas Ruf and published by Springer Science & Business Media. This book was released on 2012-04-23 with total page 549 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book summarises the newest information on seasonal adaptation in animals. Topics include animal hibernation, daily torpor, thermoregulation, heat production, metabolic depression, biochemical adaptations, neurophysiology and energy balance. The contributors to this book present interdisciplinary research at multiple levels ranging from the molecular to the ecophysiological, as well as evolutionary approaches. The chapters of this book provide original data not published elsewhere, which makes it the most up-to-date, comprehensive source of information on these fields. The book’s subchapters correspond to presentations given at the 14th International Hibernation Symposium in August 2012 in Austria. This is a very successful series of symposia (held every four years since 1959) that attracts leading researchers in the field. Like the past symposia, this meeting – and consequently the book – is aimed not only at hibernation but at covering the full range of animal adaptations to seasonal environments. For the next four years, this book will serve as the cutting-edge reference work for graduate students and scientists active in this field of physiology and ecology. .
