Sex Differences in the Nociceptive Thresholds of the Hummingbird Bobtail Squid (Euprymna berryi)
By: Abbigale Koenigsmark, Shannon Changizi, and Ingrid Ortega
Department: Physiology & Behavioral Biology
Faculty Advisor: Dr. Robyn Crook
Sex differences in nociception has been widely recognized in mammals, but no studies have investigated whether similar differences occur in invertebrates. Our project focuses on determining whether the sensory and nociceptive thresholds of male and female Euprymna berryi differ. Furthermore, we also assess whether these sex differences differ throughout squid life history. Preliminary data suggests that female squid have higher detection and nociceptive thresholds than male squids, and these differences became more dramatic as the squid ages into adulthood. We are currently increasing sample sizes in age class to more clearly define age- and sex-related differences. This study is the first to examine sex-based differences in the nociception of any invertebrate, and has so far indicated a pattern that is opposite to what is seen in mammalian groups. Our results can also help inform welfare considerations for the proper care of cephalopods in research institutions and elsewhere.