A recent study highlights potential evolutionary pathways from gliding to powered flight in bats, based on limb measurements from various mammals.
Research from the University of Washington provides new insights into bat evolution, suggesting a transition from gliding ancestors based on limb morphology analysis of extinct and extant mammals. The study challenges previous concepts of bat limb evolution and calls for more fossils to clarify this transition.
In new research published today (July 25) in PeerJ Life & Environment, researchers from the University of Washington, University of Texas at Austin, and Oregon Institute of Technology, led by undergraduate student Abby Burtner, have advanced our understanding of the evolutionary origins of flight in bats. The study, titled “Gliding toward an Understanding of the Origin of Flight in Bats,” employs phylogenetic comparative methods to explore the evolutionary transition from gliding to powered flight in these unique mammals.
Evolutionary Background and Hypothesis
Bats are the only mammals capable of powered flight, a feat enabled by their highly specialized limb morphology. However, the evolutionary pathway that led to this capability has remained elusive due to an incomplete fossil record. Burtner et al.’s research provides significant insights by testing the hypothesis that bats evolved from gliding ancestors.
Bats are unique among mammals in their ability to achieve true powered flight, a capability that allows them to maneuver with agility and speed.
Analytical Insights from Limb Measurements
The research team analyzed a comprehensive dataset of limb bone measurements that included four extinct bats and 231 extant mammals with various locomotor modes. Their findings reveal that gliders exhibit relatively elongated forelimb and narrower hindlimb bones that are intermediate between those of bats and non-gliding arboreal mammals. Evolutionary modeling of these data offers support for the hypothesis that selection may be strong on certain forelimb traits, pulling them from a glider towards a flyer adaptive zone in bats.
Conclusions and Future Directions
“We propose an adaptive landscape of limb bone traits across locomotor modes based on the results from our modeling analyses,” said Dr. Santana. “Our results, combined with previous research on bat wing development and aerodynamics, support a hypothetical evolutionary pathway wherein a glider-like forelimb morphology preceded the evolution of specialized bat wings.”
Bats are the only mammals capable of powered flight and have correspondingly specialized body plans, particularly in their limb morphology. Credit: Zdeněk Macháček
This study not only supports the gliding-to-flying hypothesis but also challenges the traditional view of bat and glider limb evolution. The researchers emphasize the need for future studies to test the biomechanical implications of these bone morphologies and to consider the complex genetic and ecological factors that influenced the evolution of bat powered flight.
“Our findings contribute to the hypothesis that bats evolved from gliding ancestors and lays a morphological foundation in our understanding of bat flight” Dr. Law added. “However, we stress that additional fossils are necessary to truly unravel the mysteries of this remarkable evolutionary transition.”
Reference: “Gliding toward an understanding of the origin of flight in bats” 25 July 2024, PeerJ.
DOI: 10.7717/peerj.17824
