DOI: 10.5061/dryad.ns341
title: Data from: Geometric morphometric character suites as phylogenetic data: extracting phylogenetic signal from gastropod shells

description: Despite being the objects of numerous macroevolutionary studies, many of
 the best-represented constituents of the fossil record—including diverse
 examples such as foraminifera, brachiopods, and mollusks—have mineralized
 skeletons with limited discrete characteristics, making morphological
 phylogenies difficult to construct. In contrast to their paucity of
 phylogenetic characters, the mineralized structures (tests and shells) of
 these fossil groups frequently have distinctive shapes that have long
 proved useful for their classification. The recent introduction of
 methodologies for including continuous data directly in a phylogenetic
 analysis has increased the number of available characters, making it
 possible to produce phylogenies based in whole or part on continuous
 character data collected from such taxa. Geometric morphometric methods
 provide tools for accurately characterizing shape variation and can
 produce quantitative data that can therefore now be included in a
 phylogenetic matrix in a non-arbitrary manner. Here, the marine gastropod
 genus Conus is used to evaluate the ability of continuous
 characters—generated from a geometric morphometric analysis of shell
 shape—to contribute to a total evidence phylogenetic hypothesis
 constructed using molecular and morphological data. Furthermore, the
 ability of continuous characters derived from geometric morphometric
 analyses to place fossil taxa with limited discrete characters into a
 phylogeny with their extant relatives was tested by simulating the
 inclusion of fossil taxa. This was done by removing the molecular
 partition of individual extant species to produce a “cladistic
 pseudofossil” with only the geometric morphometric derived characters
 coded. The phylogenetic position of each cladistic pseudofossil taxon was
 then compared with its placement in the total evidence tree and a
 symmetric resampling tree to evaluate the degree to which morphometric
 characters alone can correctly place simulated fossil species. In 33-45%
 of the test cases (depending upon the approach used for measuring
 success), it was possible to place the pseudofossil taxon into the correct
 regions of the phylogeny using only the morphometric characters. This
 suggests that the incorporation of extinct Conus taxa into phylogenetic
 hypotheses will be possible, permitting a wide range of macroevolutionary
 questions to be addressed within this genus. This methodology also has
 potential to contribute to phylogenetic reconstructions for other major
 components of the fossil record that lack numerous discrete characters.
description: a)
 Smith_Hendricks_SystBiol_ConusFiguresPlates showing examples
 of the 61 species of Conus used in this study.b)
 Smith_Hendricks_SystBiol_MatrixFilesCladistic character
 matrix files (TNT format) used to generate the total evidence phylogeny
 and molecular phylogeny (Figures 3 and 6).c)
 Smith_Hendricks_SystBiol_OutlineImageFilesDigital outline image
 files (JPEG format) used to generate coordinate point data in tpsDig for
 the eigenshape analyses (see figure 2).d)
 Smith_Hendricks_SystBiol_tpsfileThe tpsDig file
 (generated from trace image files also available here) used in the
 eigenshape analyses (see figure 2).e)
 Smith_Hendricks_SystBiol_Pseudofossil_Matrix_FilesExample matrix files
 (TNT format) for the two pseudofossil analyses shown in figure 4 (C.
 abbreviatus and C. flavidus).f)
 Smith_Hendricks_SystBiol_pseudofossil_.tre filesThe two tree files
 (generated in TNT using the matrix files available here) for the two
 pseudofossil analyses shown in Figure 4 (C. abbreviatus and C.
 flavidus).