Meeting Abstract
Spiders are among the world’s most species-rich animal lineages, and their visual systems are likewise highly diverse. These modular visual systems, comprised of four pairs of image-forming ‘camera’ eyes, have taken on a huge variety of forms, exhibiting variation in eye size, eye placement, image resolution, field of view, and sensitivity to color, polarization, light levels, and motion cues. However, despite this conspicuous diversity, our understanding of the genetic underpinnings of these visual systems remains shallow. Leveraging publicly available transcriptomic and genetic data, we evaluated hypotheses about the origins, evolution and development of spider eyes. Our analyses highlight that there are many new things to discover from spider eyes, and yet these opportunities are set against a backdrop of deep homology with other arthropod lineages. For example, many (but not all) of the genes that appear important for early eye development in spiders are familiar players known from the developmental networks of other model systems (e.g., Drosophila). Similarly, our analyses of opsins and related phototransduction genes suggest that spider photoreceptors employ many of the same genes and molecular mechanisms known from other arthropods, with a hypothesized ancestral spider set of four visual and four non-visual opsins. This deep homology provides a number of useful footholds into new work on spider vision and the molecular basis of its extant variety. We discuss what some of the most productive first steps might be in studying the vision of these fascinating creatures.
