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Data from: Fossils indicate marine dispersal in osteoglossid fishes, a classic example of continental vicariance

Capobianco, Alessio1; Friedman, Matt2

Published Jun 26, 2024 on Dryad. https://doi.org/10.5061/dryad.g79cnp5x1

Data files

Jun 26, 2024 version files 5.52 GB

Abstract

The separation of closely-related terrestrial or freshwater species by vast marine barriers represents a biogeographic riddle. Such cases can provide evidence for vicariance, a process whereby ancient geological events like continental rifting divided ancestral geographic ranges. With an evolutionary history extending tens of millions of years, freshwater ecology, and distribution encompassing widely separated southern landmasses, osteoglossid bonytongue fishes are a textbook case of vicariance attributed to Mesozoic fragmentation of the Gondwanan supercontinent. Largely overlooked fossils complicate the clean narrative invoked for extant species by recording occurrences on additional continents and in marine settings. Here we present a new total-evidence hypothesis for bonytongue fishes combined with quantitative models of range evolution and show that the last common ancestor of extant osteoglossids was likely marine, and that the group colonized freshwater settings at least four times when both extant and extinct lineages are considered. The correspondence between extant osteoglossid relationships and patterns of continental fragmentation therefore represents a striking example of biogeographic pseudocongruence. Contrary to arguments against vicariance hypotheses that rely only on temporal or phylogenetic evidence, these results provide direct palaeontological support for enhanced dispersal ability early in the history of a group with widely separated distributions in the modern day.