1. Both the development rate and sex of sea turtle embryos depend on incubation temperature, as all species of sea turtle are ectotherms and show temperature‐dependent sex determination (TSD). Theory predicts that selection should act on populations to optimize developmental times and primary sex ratios.
2. In this study, we use a consistent methodology to measure development rates and model the reaction norm that defines TSD in three populations of flatback turtles Natator depressus and two populations of green turtles Chelonia mydas that nest in Western Australia.
3. We show that development rates vary between and within species, likely reflecting adaptation to local beach microclimates. Similarly, the parameters that define the TSD reaction norm vary between the two species, and among N. depressus populations, with pivotal temperatures (T_PIV) varying by 1.5°C (29.6–31.1°C), and the transitional ranges of temperatures (TRT) varying by 1.4–3.3°C. In contrast, we found a similar T_PIV for the two C. mydas populations, but a wider TRT at the northernmost tropical rookery.
4. Our findings support the view that thermal parameters in geographically separated populations of sea turtles are broadly similar, but the variation we describe will be highly relevant for predicting how populations will respond to climate change.

中文翻译：

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热性状的变化描述了西澳大利亚海龟种群的性别决定和发育

1. 海龟胚胎的发育速度和性别都取决于孵化温度，因为所有种类的海龟都是放热体，并表现出温度依赖性性别决定（TSD）。理论预测，选择应针对人口，以优化发育时间和主要性别比例。
2. 在这项研究中，我们使用一个一致的方法来衡量发展速度和在平背海龟的三个群体定义TSD反应标准模型Natator depressus和绿海龟的两个群体绿海龟筑巢在澳大利亚西部。
3. 我们表明，物种之间和物种内部的发展速度各不相同，这很可能反映了对当地海滩小气候的适应。同样，定义TSD反应标准的参数在这两个物种之间以及在山N猪笼草种群之间也有所不同，关键温度（T _PIV）的变化范围为1.5°C（29.6-31.1°C），温度的过渡范围为（ TRT）在1.4–3.3°C之间变化。相比之下，我们发现两个C. mydas种群的T _PIV相似，但在最北端的热带种群的TRT较宽。
4. 我们的发现支持以下观点：地理上分开的海龟种群的热参数大致相似，但我们描述的变化与预测种群对气候变化的反应高度相关。