Life-history and conservation of amphibians and reptiles

我正在研究物种生活史的主要特征是如何进化的，如后代的数量和大小、成熟时的年龄、寿命和迭代性。我的方法论重点是研究这些特征在种群和物种内部和之间是如何变化的。我一直专注于海龟、蛇和青蛙，因为这些群体在较凉爽的环境中寿命更长。我的方法是将长期数据收集与短期实验相结合；在这两种情况下，关键是我正在使用被标记个人的长期数据来测试假设。这些数据使我能够将个人随时间的变化与群体内部和群体之间的变化进行比较。我的主要研究种群发生在它们物种的北部分布界限附近。每年进行标准的形态测量和人口统计测量，并测量对温度、湿度、食物、人口密度和性别比例的影响，以检验解释不同生活史模式的假设。目前，我正在研究温度如何控制分布，当性别由环境决定时，性别比例如何保持，雌性如何选择配偶，以及为什么一些脊椎动物在一生中继续生长。我特别感兴趣的是将我的研究应用于爬行动物的保护，并测试生活史如何影响长寿物种在人类压力下的脆弱性。此外，我们的长期数据使我们能够测试气温变暖对特定人口和生活史特征的影响。

I am investigating how major features of a species' life history, such as number and size of offspring, age at maturity, longevity and iteroparity have evolved. My methodological focus is to examine how these features vary within and among populations and species. I have concentrated on turtles, snakes and frogs because these groups have extended lifespans in cooler environments. My approach is to combine long-term data collection with short-term experiments; in both cases the key is that I am testing hypotheses with long-term data on marked individuals. Such data allow me to compare changes in individuals over time with changes within and among populations. My primary study populations occur near their species' northern limits of distribution. Standard morphometric and demographic measurements are taken annually and responses to manipulations of temperature, moisture, food, population density and sex ratio are measured to test hypotheses that explain different patterns of life history. Currently, I am examining how temperatures control distribution, how sex ratio is maintained when sex is determined by environment, how females select mates and why some vertebrates continue to grow throughout their lives. I am particularly interested in applying my research to conservation of reptiles and testing how life history affects vulnerability of long-lived species to anthropogenic pressures. In addition, our long-term data allow us to test for effects of warming temperatures on specific demographic and life history traits.