Williams Ecology Lab

Research Interests

I am interested in predator-prey interactions and chemical ecology.  Natural selection can be particularly powerful in these life-or-death struggles and I am fascinated by the myriad venoms and poisons that organisms produce and the corresponding physiological and behavioral counter-adaptations to this wicked weaponry. 

To address these broader interests, I study blue-ring octopuses. These charming golf-ball sized ockies flash their bright blue iridescent markings to warn potential predators of their poisonous and venomous nature. I also study the poisonous Rough-skinned Newts (common on the West Coast of the US) and its toxin-resistant garter snake predators. Why?

Both the salamander and the octopus posses the deadly neurotoxin tetrodotoxin (TTX), as do many other distantly related creatures, such as pufferfish, some chaetognaths, several molluscs, and some nudibranchs, among many others.  Because TTX is a complicated molecule and likely requires a complicated biosynthesis, it is unlikely each of these animals evolutionarily converged upon endogenous TTX production. However, evolving resistance to TTX requires just one or a few changes in the amino acid sequence of the sodium channels where TTX binds and causes toxicity. Thus, many hypothesize that TTX in these organisms is not produced endogenously, but is instead produced by symbiotic bacteria or accumulated from the diet.

These networks of predators, prey, and potential symbionts brought me from terrestrial herpetology to the big leap into marine biology and finally to the enthralling world of microbial ecology. Who knows where they will lead next!