Ryan K Schott


Research




My research interests lie broadly in how selection at the molecular level can shape morphological and functional diversity at the organismal level. I am particularly interested in complex systems and how molecular and developmental changes can lead to the evolution of complexity. I am also interested in the mechanisms of adaptation and how different groups respond to similar selective pressures. Sensory systems are an ideal model within which to study these questions, as they provide a direct interface between an organism and its environment.

Currently my research is focused on the molecular evolution and development of the vertebrate visual system. I am particularly interested in the molecular basis of the evolution of new photoreceptor cell types and how the visual system adapts to different light environments and lifestyles. To study these questions I utilize an integrative approach that combines comparative genomic, computational, and experimental techniques.

Below I briefly outline a few ongoing projects.





The Evolution of Visual Systems During Major Life History Transitions in Frogs





Frogs are a highly diverse group that exhibit a wide variety of activity periods, ecologies, life history characteristics, and behaviors. These factors are known to influence the evolution of visual systems in other vertebrates, but have not been well studied in frogs. This project aims to characterize spectral, genetic, and morphological diversification of the visual system in frogs as it relates to these major transitions. This is a joint NSF-NERC funded project led by Matthew Fujita (UT Arlington), Rayna Bell (NMNH), and Jeff Streicher (NHM).



Molecular Evolution of Phototransduction Genes





Most studies of the molecular evolution of vision focus solely on the visual opsins, but there are many other proteins involved in vision that may have undergone functional adaptation. Of particular interest are the proteins involved in the phototransduction cascade (the process of transforming a light stimulus into an electrical signal that can be sent to the brain). This process involves over 35 proteins and how these proteins have evolved and adapted in different organisms is largely unknown. Snakes and geckos are excellent systems to study the evolution of these proteins due to the frequent transitions between activity patterns (e.g., diurnality and nocturnality) and retinal compositions that have occurred in these groups.



Evolution and Function of Simplex Retinas





In order to maintain vision across the range of natural light levels vertebrates typically utilize a duplex retina that contains rod photoreceptors for dim-light vision and cone photoreceptors for bright-light vision. Snakes and geckos, however, have a predominance of simplex retinas that contain only one of these photoreceptor types. Simplex retinas can evolve either through the loss of one photoreceptor type or through evolutionary transitions between types, termed photoreceptor transmutations. The goal of this research is to determine the contribution of these two pathways to the evolution of different simplex retinas, as well as to uncover the molecular, developmental, and functional changes that accompany theses transitions.



schottr@si.edu





Ryan K Schott