geomorph: an R package for the collection and analysis of geometric morphometric shape data.

Summary Many ecological and evolutionary studies seek to explain patterns of shape variation and its covariation with other variables. Geometric morphometrics is often used for this purpose, where a set of shape variables are obtained from landmark coordinates following a Procrustes superimposition. We introduce geomorph: a software package for performing geometric morphometric shape analysis in…

Morphological convergence of shell shape in distantly related scallop species (Mollusca: Pectinidae)

Abstract Morphological convergence is a central concept in evolutionary biology, but convergent patterns remain under-studied in nonvertebrate organisms. Some scallop species exhibit long-distance swimming, a behaviour whose biomechanical requirements probably generate similar selective regimes. We tested the hypothesis that shell shape similarity in long-distance swimming species is a result of convergent evolution. Using landmark-based geometric…