Historical inheritance and expansion of morphological character sampling in macronarian sauropod phylogenetics
Year: 2026
Type: preprint
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.
Source: PaleoRxiv (OSF Preprints)
Author: Chetan Dookhy
Language: English
Subfield: Paleontology
Field: Earth and Planetary Sciences
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7214573981