While environmental factors affect animal locomotion (especially among fliers), few studies have addressed the relationship between aerial function in extinct vertebrates and paleoatmospheric conditions, and none have focused on avian flight. Our study explores the impact of varying 02 concentrations, global temperatures, and air densities on the flight performance of extinct birds. Specifically, we describe the correlation between a series of long-term atmospheric changes and major diversification events that took place during the evolution of the avian clade. We argue that variations of the above-mentioned abiotic factors impacted differently the evolutionary history of the clade over the last 180 million years (Myr). Our results show that a possible increase in 02 concentration and air density during the 130-110 Myr interval might have played a major role in the first pygostylian radiation. Our study also suggests that while paleoatmospheric changes after the KIP boundary may not have favored the early divergence of Neoaves, a probable increase in 02 levels and air density during the Eocene-Oligocene provided aerodynamic benefits that may have facilitated the evolution of bounding flight in passeriforms. Such innovation in flight gait could have contributed to the diversification of this enormous clade. While discrepancies between the atmospheric models known precludes a definitive assessment of these results, the present exploratory study highlights the potential role of the atmosphere in the evolution of birds.
|Number of pages||16|
|Publication status||Published - 2017|
|Event||International Meeting of the Society for Avian Palaeontology and Evolution - |
Duration: 1 Aug 2016 → …
|Conference||International Meeting of the Society for Avian Palaeontology and Evolution|
|Period||1/08/16 → …|