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Sam Degregori, PhD

Postdoctoral Fellow


Sam is largely interested in animal gut microbiome diversity and how it varies across the animal kingdom. A majority of gut microbiome research has focused on humans and other mammals, leaving non-mammalian clades understudied. For his PhD, Sam sampled coral reef fish gut microbiomes to better understand how host ecology and evolution shaped vertebrate gut microbiome composition. He found that the gut microbiomes of coral reef fish and mammals showed strong convergence particularly within carnivore and herbivore hosts. This striking convergence between distant hosts motivated Sam to expand beyond fish gut microbiomes and compare gut microbiomes across the entire animal kingdom. After completing his PhD at UCLA in 2022, Sam started an NSF Postdoctoral Research Fellowship with his current advisors, Dr. Katherine Amato (Northwestern University), and Dr. Rob Knight (UCSD). His postdoc will focus on constructing a large comparative dataset of published gut microbiome data to better understand how host factors shape the gut microbiome. He will also work on generating gut microbiome data on clades of hosts that have received little attention, such as reptiles and insects. Sam will combine both 16S, metagenomic and other -omic data to capture both diversity and functional aspects of the gut microbiome.  

Beyond research, Sam is also dedicated to using research as a platform to increase diversity in STEM. During his PhD, Sam mentored 22 undergraduates, many who were first-gen and/or underrepresented minorities (URMs), and participated in URM serving programs for undergraduates interested in STEM. For his postdoc, Sam plans to continue his mentoring efforts at Northwestern, with the goal of providing URM students with the skills and experience needed to succeed in STEM.