96-7 Sat Jan 2 Lens morphology is influenced by ecology in frogs and toads (Amphibia: Anura) Mitra, AT*; Womack, MC; Gower, DJ; Clark, B; Streicher, JW; Bell, RC; Schott, RK; Fujita, MK; Thomas, KN; University College London, Natural History Museum, London, UK; Utah State University, Logan, USA; Natural History Museum, London, UK; Natural History Museum, London, UK; Natural History Museum, London, UK; California Academy of Sciences, San Francisco, USA; York University, Toronto, Canada ; University of Texas, Arlington, USA; Natural History Museum, London, UK amartya.mitra@nhm.ac.uk
Lens morphology is an important aspect of vertebrate visual biology. Lens shape is typically more spherical in aquatic vertebrates (lenses) and flattened in terrestrial species to facilitate vision in different optical media. Anurans (frogs and toads) are an ecologically diverse amphibian order, with many species undergoing a shift from aquatic to terrestrial lifestyles during metamorphosis. However, the nature and extent of lens shape and size variation has not been examined over a broad phylogenetic and ecological range of species. We quantified lens shape and size using 170 CT scans of 123 anuran species across 40 of the 55 currently recognised families. Our study found that lens morphology is correlated with life stage and general ecology in anurans. Aquatic anuran larvae have spherical lenses, which are retained after metamorphosis in species with aquatic and fossorial adults. In contrast, species with ‘above ground’ terrestrial adult ecotypes, typically have more flattened lenses as adults. This study demonstrates the impact of optical media and light conditions on the evolution and development of anuran lenses and highlights the usefulness of CT data and museum specimens for studying the morphology of visual systems in vertebrates.
