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‘Small-bodied faunivore’ is the dominant ancestral ecomorphotype early in crown mammalian radiations, but it is unknown how far back this trend extends within Synapsida (the mammalian total group). To examine synapsid macroevolutionary patterns in a phylogenetic context, we built a time-calibrated meta-phylogeny of 2,128 synapsid species from the Carboniferous through Eocene (305–34 Ma), based on 211 published character matrices, each weighted according to their dependence on ‘parent’ matrices. All published character matrices focusing on non-mammalian synapsids were included, making the meta-phylogeny comprehensive for non-mammaliaform synapsids. Further, we used the most comprehensive early mammaliaform matrices. We then collected jaw length measurements (as a proxy for body size) and dietary information for 408 synapsid species (37 non-therapsid pelycosaurs, 134 non-cynodont therapsids, 46 non-mammaliaform cynodonts, 80 non-therian mammaliaforms, and 178 therians). We used the meta-phylogeny in conjunction with jaw length measurements to investigate patterns of body-size and dietary evolution during radiations of synapsid subclades. The results show that faunivory is the typical ancestral diet of each major radiation within Synapsida, but the small-to-large trend in body-size within radiations does not become established until the end-Triassic size bottleneck near the base of Mammaliaformes. Instead, ‘pelycosaur’, ‘therapsid’, and ‘cynodont’ subclades have ancestral jaw lengths that are considerably larger than non-therian mammaliaforms and therians. The shift to small ancestral body sizes is one of several aspects of the mammalian phenotype to emerge in the Late Triassic. Furthermore, by placing ‘mammaliaforms’ and mammals near their likely lower size limit, this change forced most subsequent body-size diversification to consist of trends toward larger sizes, altering macroevolutionary dynamics for the remainder of synapsid history.
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Fast mvSLOUCH: Model comparison for multivariate Ornstein--Uhlenbeck-based models of trait evolution on large phylogenies
These are the Supplementary Material, R scripts and numerical results accompanying Bartoszek, Fuentes Gonzalez, Mitov, Pienaar, Piwczyński, Puchałka, Spalik and Voje "Model Selection Performance in Phylogenetic Comparative Methods under multivariate Ornstein–Uhlenbeck Models of Trait Evolution". The four data files concern two datasets. Ungulates: measurements of muzzle width, unworn lower third molar crown height, unworn lower third molar crown width and feeding style and their phylogeny; Ferula: measurements of ratio of canals, periderm thickness, wing area, wing thickness, and fruit mass, and their phylogeny.
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- Award ID(s):
- 2225683
- PAR ID:
- 10487317
- Publisher / Repository:
- Dryad
- Date Published:
- Subject(s) / Keyword(s):
- FOS: Natural sciences model selection model selection adaptation model selection multivariate Ornstein-Uhlenbeck process multivariate phylogenetic comparative methods adaptation model selection multivariate Ornstein-Uhlenbeck process multivariate phylogenetic comparative methods Biological Scaling Feeding styles Food comminution food selectivity hypsodonty Mammalia Oral morphology Ungulata
- Format(s):
- Medium: X Size: 24120 bytes
- Size(s):
- 24120 bytes
- Sponsoring Org:
- National Science Foundation
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