title: Time-calibrated models support congruency between Cretaceous continental rifting and titanosaurian evolutionary history.
abstract: Recent model-based phylogenetic approaches have expanded upon the incorporation of extinct lineages and their respective temporal information for calibrating divergence date estimates. Here, model-based methods are explored to estimate divergence dates and ancestral ranges for titanosaurian sauropod dinosaurs, an extinct and globally distributed terrestrial clade that existed during the extensive Cretaceous supercontinental break-up. Our models estimate an Early Cretaceous (approx. 135 Ma) South American origin for Titanosauria. The estimated divergence dates are broadly congruent with Cretaceous geophysical models of supercontinental separation and subsequent continental isolation while obviating the invocation of continuous Late Cretaceous continental connections (e.g. ephemeral land bridges). Divergence dates for mid-Cretaceous African and South American sister lineages support semi-isolated subequatorial African faunas in concordance with the gradual northward separation between South America and Africa. Finally, Late Cretaceous Africa may have linked Laurasian lineages with their sister South American lineages, though the current Late Cretaceous African terrestrial fossil record remains meagre.
authors.affiliation: Department of Biological Sciences, Ohio University, 107 Irvine Hall, Athens, OH 45701, USA Ohio Center for Ecology and Evolutionary Studies, Irvine Hall, Athens, OH 45701, USA eric.gorscak@gmail.com.
authors.forename: Eric
authors.identifier: http://orcid.org/0000-0002-4019-8301
authors.initials: E
authors.lastname: Gorscak
authors.affiliation: Ohio Center for Ecology and Evolutionary Studies, Irvine Hall, Athens, OH 45701, USA Department of Biomedical Sciences, Ohio University Heritage College of Osteopathic Medicine, 228 Irvine Hall, Athens, OH 45701, USA.
authors.forename: Patrick M
authors.initials: PM
authors.lastname: O'Connor
mesh_terms: D000818:Animals; D005075:Biological Evolution; D025061:Dinosaurs / Q000145:classification*; D005580:Fossils; D005843:Geography; D008954:Models, Biological; D010802:Phylogeny; D013997:Time Factors
keywords: Gondwana; Titanosauria; palaeobiogeography; phylogenetics