SpeakerProf. Scott Gilbert (Swarthmore College) Host: Prof. Max Wilson
Date and LocationWednesday October 28, 2020 11:00am
Our bodies are not derived merely from the descendent cells of the zygote. We have an equal number of symbiotic microbes living on and in us. And whereas the human genome from our parents contains some 22,000 genes, we receive over eight million different genes from our microbial symbionts. These symbionts are important for normal development, and the differential expression of microbial genes appears to be critical in producing and sustaining our anatomical, physiological, and behavioral phenotypes. The "complete" animal, containing both the zygote-derived cells and our populations of microbes, is called a "holobiont." Recent research proposes that microbial symbionts are necessary for the development of particular organs in certain species, for the variation of selectable traits within a species, and for the emergence of particular social behaviors. One of the most interesting phenotypes induced by microbes is herbivory, the complex of anatomical, physiological, and behavioral traits allowing animals to eat plants. Herbivory will be discussed from the point of view of holobiont evolutionary developmental biology, wherein specific adaptations (such as the rumen), are seen as being induced by microbes, and the behavioral and physiological manifestations of herbivorous phenotypes need to be preceded by the successful establishment of communities of symbiotic microbes that can digest plant cell walls and detoxify plant poisons.