Ursprung und Evolutionsgeschichte moderner Amphibien - Fossilien, Morphologie und Entwicklung

• Antragstellerin: Professorin Dr. Nadia Belinda Fröbisch
• Fachliche Zuordnung: Paläontologie
• Förderung: Förderung von 2013 bis 2022
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 226152947

Despite the great diversity and ecological importance of the three groups of modern amphibians (frogs, salamanders, and caecilians), their relationships and origin(s) from fossil antecedents remain one of the major controversies of vertebrate systematics. Three competing phylogenetic hypotheses are discussed in the literature, all of which have their legitimation and have been subject to modern analytical approaches. Nonetheless, the controversy persists pertinaciously, extending into many areas of life sciences including ecology, evolution, biomedicine, and conservation, highlighting the urgent need for more data to help resolve this debate. The multidisciplinary nature of the problem, the great extant and fossil diversity of amphibians, and their ontogenetic plasticity, make them an excellent group for an interdisciplinary approach to gain a comprehensive picture of the deep time evolutionary history of this major clade of vertebrates. I here propose a novel, integrative study targeting central questions in amphibian evolution from a paleontological, morphological, and molecular perspective: (1) Salamanders display the best fossil record of all modern amphibians. A detailed study of Mesozoic and Cenozoic salamanders seeks to provide new data for assessing their controversial origin and phylogenetic relationships taking a morphological and phylogenetic approach. This is supplemented by paleontological fieldwork in the Triassic and Jurassic of Northern and Central Asia aiming to fill the crucial gap in the fossil record of amphibians to provide new insights into the evolutionary transition from ancient Paleozoic amphibians to essentially modern amphibian taxa of the Mesozoic. (2) The limb development of salamanders shows a unique pattern among tetrapods. The genetic basis of this aberrant pattern is poorly understood, but can contribute significant data to the resolution of the origin of salamanders specifically and the evolution of the tetrapod limb more generally. (3) Amphibians display by far the largest genomes among vertebrates and their genome size varies extensively, which directly impacts development, metabolism, and organ complexity. However, the evolutionary history of large genomes in amphibians is to date virtually unexplored and holds great potential for understanding evolutionary, developmental, and phylogenetic patterns. These three subprojects are highly integrated and the gained insights of each one inform the other subprojects to generate a body of new, cutting edge data. In concert with modern analytical approaches, this greatly expanded dataset will further the understanding on amphibian origins and evolution through deep time.

• DFG-Verfahren: Emmy Noether-Nachwuchsgruppen