Tara Adiseshan set out to solve an evolutionary puzzle when she conducted her research on the long-term relationship between sweat bees and nematodes (microscopic worms) that live inside them. Specifically, the 14-year-old junior at Ramana Academy, Charlottesville, VA, hypothesized that sweat bees and nemotodes, which demonstrate a symbiotic relationship, had been undergoing cospeciation, the process of evolving in response to and in concert with each other, since ancient times.

By examining genetic material from multiple species of sweat bees that host nematodes, Adiseshan was able to construct a phylogenetic tree for the bees and then compare the data with an existing phylogenetic tree for nematodes. The comparison of the congruent phylogenies showed clear evidence of co-cladogenesis, supporting the theory that the relationship between sweat bees and nematodes is ancient, with speciation events in the hosts resulting in speciation events in the symbiotes.

Adiseshan’s work provides a greater understanding of these organisms, as well as additional insight into evolutionary history.

Interests in environmental science and public health led Li Boynton to consider new methods for testing the quality of drinking water. Observing the limitations and significant expense of conventional chemical-specific tests, Boynton saw a need for a broader, more efficient assay for testing. This led the 17-year-old junior from Bellaire High School, Bellaire, Texas, to consider the non-pathogenic, bioluminescent bacterium Vibrio fischeri as a possible biosensor for contaminants.

Specifically, Boynton examined the effect of six common water contaminants – mercury, sodium nitrate, zinc sulfate, copper sulfate, the herbicide Atrazine and the pesticide Permetherin – on the bioluminescence of V. fischeri.

Results showed a clear correlation between the light intensity of the bacteria cultures and the presence and toxicity of contaminants, indicating that the bacterium may be viable as a fast, economical method of detecting a broad range of toxins often found in drinking water supplies.

Boynton’s research could be significant in improving public health, worldwide.

Olivia Catherine Schwob has always been interested in cognitive science. As a result, her project, How Worms Learn, examines the effect of Mammalian gene expression on associative conditioning, a type of learning, in Caenorhabditis elegans, a small roundworm commonly used as a model organism in laboratory research related to humans.

Specifically, Schwob hypothesized that GAP-43, a mammalian gene proven to be associated with learning in humans, would improve learning in C. elegans. To test her theory, the 16-year-old junior at Boston Latin School, Boston, MA, extracted the gene from a mouse and used it to create a fusion protein construct which she then injected the gonads of C-elegans to create progeny expressing GAP-43. The results? GAP-43 significantly stimulated learning in the organism.

Schwob’s research will help scientists better understand how humans learn and, one day, may even be useful in treating or preventing mental disabilities.