Marine Biology Seminar: Dr. Samantha Leigh (California State University, Fullerton)
"You are what you eat: Nutritional Physiology in Fishes Influences Ecology"
Abstract: The phrase "You are what you eat" is not as simple as it seems. What an animal consumes and what an animal actually assimilates to meet energetic demands are not always synonymous. For example, sharks, generally accepted as carnivores, have guts that are presumed to be well suited for a high protein diet. However, the bonnethead shark has been shown to consume copious amounts of seagrass, despite having stereotypical "carnivore" gut morphology. If this shark does in fact digest and assimilate seagrass nutrients, what does this mean for the extremely valuable, yet fragile, seagrass ecosystems in which they reside? And what about animals who are not consuming food at all, but instead ingesting plastic pollution generated by humans? What would this mean for their physiology and their roles in ecosystem dynamics? This talk will focus on commercially and ecology important marine species in order to understand how they may adjust their feeding and digestive strategies based on changes to their environment. This includes the entire digestive process: from ingestion to excretion and even how microbes impact the processes in between.