Skip to main content
Browse by:

Biology Seminar | Dr. Daniel Speiser, Department of Biological Sciences, University of South Carolina | A kaleidoscope of eyes: advantages, constraints, and evolutionary histories of distributed visual systems

Understanding the perceptual worlds of animals involves trying to see the world through their eyes. But what if an animal has dozens of eyes and lacks anything easily recognized as a brain? These sorts of distributed visual systems can include dozens to even hundreds of eyes and they are associated, in many cases, with nervous systems that have fundamentally different architectures than those of animals with only a pair of eyes on their head. In the Speiser Lab, we have been studying how these distributed visual systems function and how and why they have evolved. Despite having relatively simple and decentralized nervous systems, animals with distributed visual systems, such as scallops and chitons, are able to detect, locate, and target visual cues. From this, we have learned that these many-eyed molluscs produce spatially coherent neural representations of their external surroundings by integrating the hundreds of overlapping images captured separately by their eyes. Our most recent work is beginning to reveal how scallops and chitons produce neural maps of their external environments and how they convert visual input to behavioral output rapidly and efficiently. Our work on distributed visual systems also addresses how novel sensory modalities originate in lineages and how sensory organs and nervous systems co-evolve. For example, the distributed visual systems of scallops and chitons both appear to have evolved (in some cases quite recently) through modifications to sensory-motor networks with ancestral chemo-tactile functions. From this, we argue that distributed sensory systems illustrate how relatively unremarkable changes in structure can lead to significant and rapid changes in function, including the origin of entirely new sensory modalities such as vision.

Contact: Blythe Boquist