Dr. Katerina Semendeferi

Katerina Semendeferi is Professor of Anthropology and Director of the Laboratory for Human Comparative Neuroanatomy at UC San Diego. Originally from Thessaloniki Greece, she completed her graduate and postgraduate training in Biological Anthropology, Neurosciences and the program in Cognitive Neuroscience at the University of Iowa before joining the faculty at UC San Diego.  Semendeferi’s scientific inquiry in “what makes us human” is grounded in the comparative study of the brain. Her long-standing commitment to noninvasive approaches to study the brain, helped her pioneer new ways to gain insights into the neuroanatomy of great apes, our closest living relatives, compared to humans. More recently she begun to explore links between the phylogenetically reorganized brain regions and their implication in vulnerabilities observed in atypical human neurodevelopment.

Her work demonstrated that, contrary to dominant views, the relative size of the frontal cortex is remarkably similar across apes and humans (PMID: 11850633) and that instead of an overall disproportionate enlargement of this functionally important part of the brain, evolutionary modifications took place in more subtle aspects of the anatomy, like specific areas within the frontal lobe, density of neurons, cortical layers, neuronal subtypes and in interconnected subcortical nuclei like the amygdala (PMID: 21098620; PMID:22473387). These findings point to a phylogenetically recent reorganization of circuitry (PMID: 24904348) that may be critical to the emergence of altered communication between brain regions regulating human-specific cognitive and emotional functions (PMID: 31703898). Atypical neurodevelopment in these same systems underlie Autism (ASD) (PMID: 22068992) and Williams Syndrome (WS) (PMID: 32189114; PMID: 30501059; PMID: 28848376) with some neural alterations taking place in opposing directions, as recently discovered (PMID: 32024554). Both ASD and WS are characterized by distinct socio-cognitive abilities and can thus help elucidate the evolutionary interplay between genes, environment, brain structure and behavior (PMID: 25247986; PMID: 31260092).

Semendeferi’s interest in the field of comparative neuroanatomy goes beyond the pursuit of discoveries in her own laboratory. Her initiatives triggered transformations in the field of human brain evolution and the comparative study of the ape brain in the last two decades. Early on she established collaborations with zoos and veterinarians across the U.S. aimed to make available to science the brains of apes, following the natural death of individual animals (PMID: 11241188; PMID: 9637180). Precious tissue, previously disposed of, started to be systematically collected and then curated by her and others leading to large and unique data sets available to scientists around the world.

Semendeferi initiated the application of structural Magnetic Resonance Imaging technology on postmortem ape brain specimens (PMID: 9085187) and a postdoctoral NIH fellowship allowed her to pursue the initiation of scanning of the brain of living apes with collaborators at the Yerkes Primate Research Center which led to the successful testing and application of the novel noninvasive technology on the brain of an initial cohort of apes and humans (PMID: 10656781).  These early initiatives planted the seeds for the establishment of ape and other primate brain banks and the subsequent larger scale application of noninvasive imaging techniques on living apes in the U.S. Numerous dissertations and hundreds of scientific papers can be linked to the resources she first pursued and the partnerships she fostered over time.

Semendeferi is currently collaborating with pioneers in the field of induced pluripotent stem cells and brain organoids in an effort to bridge human neuroanatomy with this novel technology using living cells in the dish (PMID: 27509850) in ways that can be mutually informative and move the field of human brain evolution to the future (PMID:30730291; Science 2021). In her laboratory she analyzes postnatal and adult human tissue in partnership with the University of Maryland Brain and Tissue Bank, a repository of the National Institutes of Health NeuroBioBank. Fetal human brain tissue sections are housed in collections at the National Museum of Health and Medicine, Washington D.C.

Although her specialization is in human comparative neuroanatomy, Semendeferi has been exposed to other approaches to the study of human evolution, including the fossil record, and maintains a sustained interest in bringing together multiple fields of inquiry (PMID: 24194709; PMID: 29533941). She was involved in archeological and paleoanthropological excavations in the United States, Europe and Asia and has been teaching undergraduate and graduate courses on Human Origins, Human Comparative Neuroanatomy, Human Brain Evolution, Honors Studies in Anthropology, core graduate seminar in Biological Anthropology and other courses. She has a commitment to training and mentoring a diverse student body, including first generation college students, underrepresented minorities, women of various ethnic backgrounds and others.  Semendeferi is the recipient of the Faculty Outstanding Mentor Award for Marshall College at UC San Diego. She gave the James Arthur Lecture on Human Brain Evolution in the American Museum of Natural History in NY and is faculty in the Neuroscience Program, advisory board member of the Kavli Institute for Brain and Mind, and internal adviser for the Center of Academic Research and Training in Anthropogeny (CARTA) at UC San Diego. She is Elected Fellow of the American Association for the Advancement of Science.