Researchers from the University of Washington, University of Texas at Austin, and Oregon Institute of Technology, led by undergraduate student Abby Burtner, have recently unveiled new findings in PeerJ Life & Environment that sheds new light on the evolutionary origins of flight in bats. The study utilizes phylogenetic comparative methods to delve into the transition from gliding to powered flight in these remarkable mammals.
Bats’ unique ability for powered flight sets them apart from other mammals, and their specialized body plans, especially in limb morphology, offer a fascinating area for study. The study provides valuable insights into the hypothesis that bats evolved from gliding ancestors, furthering our knowledge of this complex evolutionary process.
The team’s analysis of limb bone measurements, encompassing four extinct bats and 231 extant mammals with various locomotor modes, has yielded intriguing findings. It appears that gliders possess relatively elongated forelimb and narrower hindlimb bones, positioning them between bats and non-gliding arboreal mammals.
The data also suggests that there may be strong selection pressure on specific forelimb traits, potentially driving them from a glider toward a flyer adaptive zone seen in bats.
“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.”
This study provides compelling support for the gliding-to-flying hypothesis and presents a nuanced challenge to the established understanding of bat and glider limb evolution. The researchers stress the importance of conducting further studies to assess the biomechanical implications of these bone morphologies and to explore the intricate genetic and ecological factors that have shaped the evolution of bat-powered flight.
“Our findings contribute to the hypothesis that bats evolved from gliding ancestors and lay 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.”
Journal reference:
- Abigail E. Burtner, David M. Grossnickle, Sharlene E. Santana, Chris J. Law. Gliding toward an understanding of the origin of flight in bats. PeerJ Life & Environment, 2024; DOI: 10.7717/peerj.17824