Dead Fish Breathes New Life Into the Evolutionary Origin of Fins and Limbs
Published:24 Oct.2022 Source:University of Bristol
The discovery, by an international team, led by Min Zhu of the Institute of Vertebrate Palaeontology and Palaeoanthropology, Bejiing and Professor Philip Donoghue from the University of Bristol's School of Earth Sciences, shows the primitive condition of paired fins before they separated into pectoral and pelvic fins, the forerunner to arms and legs. Corresponding author Min Zhu of VPP, Beijing, added “Tujiaaspis shows the primitive condition for paired fins first evolved. Nevertheless, we can see vestiges of elongate fin-folds in the embryos of living jawed fishes, which can be experimentally manipulated to reproduce them. The key question is why did fins first evolve in this way?”
Co-author Dr Joseph Keating at Bristol modelled the evolution of paired fins. He said: "Fossil jawless vertebrates display a dizzying array of fin types, which has provoked extensive debate about the evolution of paired fins. “Our new analyses suggest that the ancestor of jawed vertebrates likely possessed paired fin-folds, which became separated into pectoral and pelvic regions. Eventually, these primitive fins evolved musculature and skeletal support, which allowed our fishy ancestors to better steer their swimming and add propulsion. It is amazing to think that the evolutionary innovations seen in Tujiaaspis underpin locomotion in animals as diverse as birds, whales, bats and humans.”