Ciara OâDonovan, Andrew Meade & Chris Venditti (2018)
Dinosaurs reveal the geographical signature of an evolutionary radiation.
Nature Ecology & Evolution (2018)
Supp. material is free
Dinosaurs dominated terrestrial ecosystems across the globe for over 100âmillion years and provide a classic example of an evolutionary radiation. However, little is known about how these animals radiated geographically to become globally distributed. Here, we use a biogeographical model to reconstruct the dinosaursâ ancestral locations, revealing the spatial mechanisms that underpinned this 170-million-year-long radiation. We find that dinosaurs spread rapidly initially, followed by a significant continuous and gradual reduction in their speed of movement towards the Cretaceous/Tertiary boundary (66âmillion years ago). This suggests that the predominant mode of dinosaur speciation changed through time with speciation originally largely driven by geographical isolationâwhen dinosaurs speciated more, they moved further. This was gradually replaced by increasing levels of sympatric speciation (species taking advantage of ecological opportunities within their existing environment) as terrestrial space became a limiting factor. Our results uncover the geographical signature of an evolutionary radiation.
Dinosaurs were 'too successful for their own good'