NSF Postdoctoral Fellowship in Biology FY 2021: NAVIGATING THE DARK: EXTREMOPHILE SENSORY CONVERGENCE IN CAVES

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2021, Integrative Research Investigating the Rules of Life Governing Interactions Between Genomes, Environment and Phenotypes. The fellowship supports research and training of the fellow that will contribute to the area of Rules of Life in innovative ways. Extremophiles are a fascinating group of organisms that live in harsh and unforgiving environments; they thrive in the darkest depths and the hottest habitats.

One of these extreme habitats includes the subsurface habitat of caves. Harsh conditions including no light, frequent flooding, and scarce resources have led to extreme adaptations that nonetheless are very similar in different animals (e.g. salamanders and fishes); this is known as convergent evolution. Research on convergent evolution in caves has focused on traits that have been lost (e.g., eyes), but characteristics considered constructive, or additive, have received little attention.

Constructive traits include enhanced non-visual sensory perception, thought to be a crucial adaptive trait allowing these organisms to move about efficiently in their environment. Studies of constructive adaptive traits in cavefishes have led to breakthroughs in under-water radar technology, human biotechnology, and human medicine including an intravenous flow sensor.

Understanding both the genetic basis and the physical attributes of these constructive traits will provide a greater variety of bioinspiration for technology. The future of biology is in biocomputing, and underrepresented groups are traditionally not provided opportunities by our systems to learn these skills. The fellow is dedicated to training the next generation of women and underrepresented scientists through workshops, class offerings, and active recruitment.

The goal of the project is to better understand the molecular basis and morphology of the convergent hypertrophied (enhanced) mechanosensory (or tactile) lateral line system in cave-adapted fishes. The lateral line allows aquatic organisms to feel the movement of the water around them to navigate their environment. The first objective of the project is to examine the molecular (genomic and transcriptomic) basis for lateral line hypertrophy.

The second object is to assess lateral sensitivity (i.e., degree of hypertrophy) through behavioral experimentation. The fellow will examine how the molecular basis of lateral line hypertrophy could impact the morphology and sensitivity of the lateral line through mechanosensory sensitivity experiments. This will be the first project to examine convergent evolution of a constructive cave-adaptive trait using both molecular and morphological means, opening the door to understanding the multiple levels of extremophile convergence in the dark.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.