The role of growing degree-days in explaining moth species distributions at broad scales

Growing degree-days (GDD), an estimate of an organism’s growing season length, has been shown to be an important predictor of Lepidopteran species’ distributions and could be influencing Lepidopteran range shifts to climate change. Yet, one understudied simplification in this literature is that the same thermal threshold is used in the calculations of GDD for all species instead of a species-specific threshold. By characterizing the phenological process influenced by climate, a species-specific estimate of GDD should improve the accuracy of species distribution models (SDMs). To test this hypothesis, we use published lab-estimated thermal thresholds and modeled the current geographic distribution of 30 moth species native to North America. We found that the predictive performance of models based on a species-specific estimate of GDD was indistinguishable from models based on a standard estimate of GDD. This is likely because GDD was not an important predictor of these species’ distribut..., , , # The role of growing degree-days in explaining moth species distributions at broad scales

Data used to generate the species' BDT and assess how the quality of the experiments may have influenced the accuracy of BDT.

**Description of the Data and file structure**

quality_test.csv: data used to assess the quality of the experiment that generated the base development temperature for the 30 species used in the analysis

Column names, Definition, Units

BDT: Base development temperature estimate from the experiment; in degrees Celsius
ltm: lowest temperature treatment included in the experiment, stages included; in degrees Celsius
adj_ltm: adjusted lowest temperature treatment included in the experiment if more than one ltm was provided; took the mean if the ltm was different for different life stages; in degrees Celsius
ltd: lowest temperature with data on developmental rate (i.e., mortality or no development detected at temperature treatments lower than this, if different from lowest t...

生长度日（Growing degree-days, GDD）是估算生物体生长季长度的指标，已有研究证实其是鳞翅目（Lepidopteran）物种分布的重要预测因子，或可驱动鳞翅目物种因气候变化发生的分布范围迁移。然而该研究领域存在一个尚未得到充分关注的简化处理：现有GDD计算中对所有物种统一使用通用温度阈值，而非针对各物种的专属阈值。鉴于气候会影响物候过程，基于物种专属阈值的GDD估算本应提升物种分布模型（Species Distribution Models, SDMs）的预测精度。为验证这一研究假说，本研究采用已发表的实验室估算温度阈值，对北美本土30种蛾类的当前地理分布进行建模分析。结果显示，基于物种专属GDD估算的模型预测性能，与基于通用GDD估算的模型并无显著差异。这可能是由于生长度日并非这些物种分布的重要预测因子……，，，# 大尺度下生长度日在解释蛾类物种分布中的作用

本数据集用于生成物种基础发育温度（Base Development Temperature, BDT），并评估实验质量对BDT精度的影响。

**数据与文件结构说明**
quality_test.csv：用于评估本分析所用30个物种的基础发育温度实验质量的数据集

列名 定义 单位
BDT：实验得到的基础发育温度估算值；单位为摄氏度
ltm：实验中包含的最低温度处理、涵盖的发育阶段；单位为摄氏度
adj_ltm：当实验提供多个最低温度处理时的校正后最低温度处理；若不同发育阶段的ltm存在差异，则取其平均值；单位为摄氏度
ltd：记录发育速率数据的最低温度（即若在低于该温度的处理组中检测到死亡或无发育现象，且该温度与最低处理温度不同时的临界温度）……