Lost in the Other Half: Improving Accuracy in Geometric Morphometric Analyses of One Side of Bilaterally Symmetric Structures

• DOI: 10.1093/sysbio/syw043
• Publication Date: 2016-06-11T05:18:15Z
• Authors: Andrea Cardini
• Keywords: Mirroring; Morphometrics; Congruence (geometry)

Systematists and evolutionary biologists have widely adopted Procrustes-based geometric morphometrics for measuring size shape in biology. Many structures, fact most animals, are bilaterally symmetric with an internal plane of symmetry (also called object symmetry). Often, when quantifying asymmetric variation is not aim, only one or the other side measured analyzed. This approach has been used hundreds studies. Its implicit assumption that information on redundant a single will, therefore, produce results mirroring those would obtained from analysis entire structure all its left right landmarks. However, extent to which this met has, my knowledge, never explored. Using two example data sets, I will show congruence may be high analyses at macroevolutionary level but much lower microevolutionary one, inaccuracies might especially affect shape. discuss some factors influence suggest simple expedient can improve both visualization accuracy one-side-only