Historical inheritance and expansion of morphological character sampling in macronarian sauropod phylogenetics
Abstract
Morphological phylogenetic matrices are often treated as discrete datasets even when they descend from shared character lists. The study used the frozen MacronariaMatrix v1.0.0 crosswalk to quantify the historical structure of character sampling across eight selected macronarian and titanosauriform sauropod matrices published from 2009 to 2026. The database resolves 2,377 matrix occurrences into 855 canonical character concepts and records explicit reformulation, split, merge, and decomposition relationships. Early Wilson-derived matrices show very high concept overlap (Jaccard 0.918--0.963), whereas the 2019 matrix represents the largest expansion of the sampled concept pool, adding 366 concepts relative to earlier sampled years; the 2026 matrix retains 99.6% of that 2019 concept inventory. Across the series, 63.3% of concepts occur in only one or two matrices, although the two-matrix mode is dominated by concepts shared only by the historically linked 2019 and 2026 datasets. Later matrices also shift proportionally from cranial/dental toward axial character sampling. These results show that raw matrix size conflates inheritance, reformulation, and addition, and that historical dependency should be considered when morphological matrices are compared as datasets.
Related
- MacronariaMatrix: a curated cross-matrix database of morphological phylogenetic characters in macronarian sauropods
- Decoupling Taxon Completeness and Phylogenetic Instability in Macronarian Sauropod Morphological Datasets
- Walking alone to the north: The origin and historical expansion of the polyploid parthenogenetic lineage in a weevil
- Out of the cradle: expansion from the natal ecosystem erodes morphological specificity in endemic Kamchatkan charrs (genus Salvelinus)
- Puzzling parasitic plants: phylogenetics and classification of Santalales revisited
BibTeX
@misc{dookhy2026historical,
title = {{Historical inheritance and expansion of morphological character sampling in macronarian sauropod phylogenetics}},
author = {Chetan Dookhy},
howpublished = {PaleorXiv},
year = {2026},
month = sep,
doi = {10.31233/osf.io/h2jfb_v1},
url = {https://osf.io/preprints/paleorxiv/h2jfb_v1/},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Historical inheritance and expansion of morphological character sampling in macronarian sauropod phylogenetics
AU - Chetan Dookhy
PY - 2026
DA - 2026/09/28
PB - PaleorXiv
DO - 10.31233/osf.io/h2jfb_v1
UR - https://osf.io/preprints/paleorxiv/h2jfb_v1/
AB - Morphological phylogenetic matrices are often treated as discrete datasets even when they descend from shared character lists. The study used the frozen MacronariaMatrix v1.0.0 crosswalk to quantify the historical structure of character sampling across eight selected macronarian and titanosauriform sauropod matrices published from 2009 to 2026. The database resolves 2,377 matrix occurrences into 855 canonical character concepts and records explicit reformulation, split, merge, and decomposition relationships. Early Wilson-derived matrices show very high concept overlap (Jaccard 0.918--0.963), whereas the 2019 matrix represents the largest expansion of the sampled concept pool, adding 366 concepts relative to earlier sampled years; the 2026 matrix retains 99.6% of that 2019 concept inventory. Across the series, 63.3% of concepts occur in only one or two matrices, although the two-matrix mode is dominated by concepts shared only by the historically linked 2019 and 2026 datasets. Later matrices also shift proportionally from cranial/dental toward axial character sampling. These results show that raw matrix size conflates inheritance, reformulation, and addition, and that historical dependency should be considered when morphological matrices are compared as datasets.
ER -