Meeting Abstract

92.4  Friday, Jan. 7  Ontogeny of tetrodotoxin levels in blue-ringed octopuses: Maternal investment as well as independent production in offspring of Hapalochlaena lunulata WILLIAMS, B.L.*; HANIFIN, C.T.; BRODIE, JR., E.D.; CALDWELL, R.L.; New Mexico State University; Hopkins Marine Station, Stanford University; Utah State University; University of California, Berkeley toxwilliams@gmail.com

Many organisms provision offspring with antipredator chemicals. Adult blue-ringed octopuses (Hapalochlaena spp.) harbor tetrodotoxin (TTX), which may be produced by symbiotic bacteria. Regardless of the ultimate source, we find that females invest TTX into offspring, as offspring TTX levels are significantly correlated with female TTX levels. Because diversion of TTX to offspring begins during the earliest stages of egg formation, when females are still actively foraging and looking for mates, females may face an evolutionary tradeoff between provisioning larger stores of TTX in offspring and retaining that TTX for their own defense and offense. Given that total TTX levels appear to increase over development and female TTX levels correlate with those of offspring, investment may be an active adaptive process. Even after eggs have been laid, TTX levels continue to increase, suggesting that offspring or their symbionts later begin producing TTX independently. The maternal investment of TTX in offspring of Hapalochlaena spp. represents a rare examination of chemical defenses, excepting ink, in cephalopods.