Research Symposium

BIO

I am a Freshman from St. Louis, Missouri majoring in psychology and pursuing a career in Clinical Psychology. I’m very interested in neurological, biological, and psychological advancement and plan to continue researching throughout my undergraduate and graduate years.

Chemosensory Evolution in the Blind Mexican Cavefish

Abstract

Having evolved in a cave environment, blind Mexican cavefish (Astyanax mexicanus) have developed enhanced non-visual senses to compensate for their lack of vision. This study investigates the behavioral changes in response to odorants as a result of this change in sensory input. The study involves comparing the behavioral response of blind Mexican cavefish and closely related surface fish, who have maintained sight and physical eyes, to
various concentrations of different odorants. The study evaluates behavioral responses to odorants in multiple contexts, in both adults and juveniles. By recording their behavioral movements in these different conditions, our goal is to find differences in the chemosensory response of blind Mexican cavefish compared to surface fish. We have found increased behavioral response to both attractive and aversive odorants in cavefish relative to surface conspecifics, in the form of alterations in their proximity to the stimulus source.
This study provides a basis to evaluate the behavioral adaptations that have emerged as a result of adaptation to the cave environment, and will aid in understanding how organisms adapt to extreme conditions such as a complete absence of light. This study also provides insight into the behavioral effects of circuit-level and molecular adaptations, which can reveal how evolutionary processes shape organismal function.

Keywords: Chemosensory Evolution Behavior Cavefish