Abstract
Pleurocerid snail diversity has historically been defined by morphological shell features, and these features are believed to be phenotypic responses to environmental factors. More recently, authors have shown the importance of genetics in shell variability, even to the exclusion of any environmental effect. Work by Dillon on Elimia proxima in the 1980s aimed to address this genetic versus environmental correlation of shell features, without reaching a solid conclusion. Using Dillon’s original data and specimens, geometric morphometric analysis was used in a phylogenetic context to show that E. proxima shell variation at the population level is correlated with genetics and not with the environment. This data is the latest example to find that shell variation as the result of environmental factors is too simplistic an explanation in pleurocerids.
