ArmLengthConversion.xlsx

Conversion for Pisaster ochraceus Arm Length Measurements To enable P. ochraceus size comparisons between California and Oregon and to allow other researchers to easily convert between arm lengths using different published methods, we measured arm lengths of 25 sea stars ranging in arm length from ~5-200mm at each of 6 sites in Oregon (see manuscript) using both measurement approaches. To determine whether site influenced this conversion, we first ran a linear model with madreporite measure as the response variable and site and center measure as the interacting factors. No interacting effect of site and arm measurement from center to arm tip was found (F5,138 = 0.64, P = 0.672), suggesting this metric is consistent geographically, at least within Oregon. We had no data for California. So, we used a simple linear regression (R2 = 0.97, P &lt; 0.001) to convert madreporite measures to center measures for all our data. Conversion formulas in centimeters are: [madreporite arm length = 4.074 + (1.060*center arm length)] or [center arm length= -0.729 + (0.914*madreporite arm length)].紫赭海盘车腕长测量转换方法 为实现加利福尼亚州与俄勒冈州两地紫赭海盘车（Pisaster ochraceus）的体型对比，并方便其他研究人员依托已发表的不同测量方法完成腕长数据的便捷转换，我们采用两种测量方案，对俄勒冈州6个采样点（详见研究手稿）各25只腕长范围约5~200mm的海星进行了腕长测量。为探究采样点是否对该转换关系存在影响，我们首先构建了线性模型：以筛板测量值为响应变量，以采样点与中央测量值为交互因子。未检测到采样点与腕中心至腕尖测量值间的交互效应（F5,138=0.64，P=0.672），表明该测量指标在地理上具有一致性，至少在俄勒冈州范围内如此。我们未获取加利福尼亚州的相关数据，因此针对全部数据集，我们采用简单线性回归（决定系数R²=0.97，P<0.001）完成筛板测量值至中央测量值的转换。以厘米为单位的转换公式如下：【筛板腕长 = 4.074 + (1.060 × 中央腕长)】或【中央腕长 = -0.729 + (0.914 × 筛板腕长)】。