Maternal Effects in the Western Painted TurtlePainted turtles are an interesting system to study the significance of maternal effects, specifically with regard to nesting behavior. Females lay eggs in underground nests during the summer and leave them with no additional parental care. The eggs hatch in the Fall, and hatchlings remain in their nest until the following Spring. This places a high degree of importance on where a mother decides to nest because eggs are at the mercy of their environment, and development of reptile eggs is famously sensitive to surrounding conditions. The effect of maternal nesting behavior on offspring in the field has been studied before, but experimental manipulations under field conditions are few and far between.
My work on painted turtle nesting behavior manipulates two nest variables, shade cover and distance to water, under field conditions to pinpoint the importance of each in generating variation in offspring hatching success. Each of these variables have been shown to affect offspring survival, but the degree and direction of effects is less well understood. The results of the experiment, paired with a long-term study on maternal nest choice at this site, provide support for the idea that maternal nesting behavior has the potential to be adaptive. |
Anolis lizards are a popular study system for addressing questions in evolution, behavior, and ecology, but we know surprisingly little about their nesting behavior. There have been a few field studies and observations of anole nesting, but none that quantified microhabitat choice or the effects of microhabitat on hatching. Furthermore, anoles lay one egg per week across a long reproductive season, which creates the opportunity for temporal variation in nesting behavior and its downstream effects. This temporal component has also gone largely unexamined.
My work on anole nesting is aimed at tackling some of these knowledge gaps by examining nesting behavior of A. sagrei in the field, determining the effects of microclimate conditions on hatching success, and examining temporal variation in both of these components. This work has generated the largest data set to date for anole nest site choice in the field and illuminates which variables females select for during oviposition. Furthermore, these data provide necessary context for future lab studies on developmental effects of incubation conditions by giving a degree of ecological relevance that was previously lacking. |
Decades of research have shown that developmental environment plays a crucial role in shaping phenotypes and determining individual fitness. This has been examined in the brown anole relatively thoroughly, but there are still a few notable gaps. The main goal of my work is to address unanswered questions on what contributes to variation in developmental thermal reaction norms and how developmental conditions affect later life stages by combining lab and field work.
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