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Showing 1 to 6 of 6 for “"egg retention"”.
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Life history evolution of the lizard Sceloporus scalaris: comparisons of lowland and montane populations
… m) populations exhibit short and long periods of egg retention, respectively, and increased periods of egg retention are presumably an intermediate step in the evolution of viviparity. Low elevation populations had life histories typical of lowland Sceloporus: eggs are laid at embryonic stages …
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Constraints on the Evolution of Viviparity in the Lizard Genus Sceloporus
… by experimentally extending the length of egg retention past the normal time of oviposition for a number of oviparous species. Observations also included a representative of the genus Urosaurus, the sister genus to Sceloporus. I determined the effects of retention on embryonic development, …
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Physiological and Ecological Constraints on the Evolution of Viviparity in Sceloporine Lizards
… to support embryonic development during extended egg retention. I incubated eggs of sceloporine lizards under conditions that simulated retention in the oviduct under a range of oxygen partial pressures. In Chapter one, I tested the hypothesis that embryos of the oviparous lizard Sceloporus …
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Seasonal Changes in the Morphology of the Uterus of the Oviparous Lizard <em>Saproscincus mustelinus</em> and the Reproductively Bimodal Lizard <em>Saiphos equalis</em>.
… many changes including an increase in oviductal egg retention times, a decrease in thickness of the eggshell and a decrease in secretion of the uterine shell glands that are responsible for eggshell secretion. The uterine morphology of the oviparous <em>Saproscincus mustelinus</em> and the …
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Reproductive Resilience of Aedes Aegypti Mosquitoes
… hosts that provide blood proteins required for egg development, conspecific males that provide sperm required for fertilization, and freshwater in natural or manmade containers that serves as an egg-laying substrate suitable for offspring survival during larval and pupal stages. As global …
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Regulation of the hif-1-dependent hypoxic stress response by C. elegans
… adaptive changes in C. elegans, including retention of eggs in the uterus, decreases in locomotion and defecation rates, and increased resistance to not only hypoxia but also other stresses including oxidative stress and ER stress. By identifying suppressors of the egl-9(lf) mutant …