Tuesday, November 15 4:02 pm
Ryan studied dinoflagellates in near-complete darkness experimentation areas. Photo courtesy of Ryan.
Puerto Rico is one of the few places on Earth with bioluminescent bays. A favorite destination for tourists, these inlets glow at night when swimmers agitate the waters’ light-emitting dinoflagellates, or tiny photosynthetic microbes.
Seventeen-year-old Ryan wanted to understand whether the popular insect repellant DEET, worn by many tourists to ward off mosquitoes, had any effect on the dinoflagellates in these bays. His investigation, outlined in the essay The Effects of DEET on the Bioluminescent Dinoflagellate, Pyrocystis fusiformis, earned Ryan one of this year’s Young Naturalist Awards.
Ryan hypothesized that the presence of DEET in the water would adversely affect the dinoflagellates’ ability to luminesce. To test his prediction, Ryan used black garbage bags and duct tape to convert wooden shelves into near-complete darkness experimentation areas. He added several solutions with varying concentrations of DEET to flasks filled with dinoflagellates, also monitoring a control group that contained distilled water. After setting a timed lamp to mimic 12-hour cycles of daylight and darkness, Ryan agitated each culture with a swirl and measured their illuminance with a light sensor. Read more »
Thursday, November 03 11:24 am
Here, Rachel identifies the gender of beetles in her experiment. Photo courtesy of Rachel.
Over a year ago, Rachel braved cold winds and snow to study winter insects called gallflies, winning a 2010 Young Naturalist Award for the research essay she wrote about their complex life cycles. In the summer, Rachel set out again—this time, to search cow pastures for coprophilous beetles, known commonly as dung beetles, which would become the subject of another research project.
The more Rachel learned about the dung beetle’s role in reintroducing nutrients from cow dung back into the soil, the more interested she became in the humble dung pat as an ecosystem of its own. Rachel received her second Young Naturalist Award for her investigation on the relationship between dung beetles and the height and biomass of pasture plants. She describes her process in the essay Tiny Allies: The Effect of Coprophilous Beetles on Brassica rapa and Lolium perenne Growth and Biomass. Read more »
Friday, October 28 9:47 am
Sara conducted an experiment to see how environmental stresses affected the oil yield of algae. Photo courtesy of Sara.
Fifteen-year-old Sara knew that vegetable oils could be used as biofuels. But when she learned that algae might offer an alternative fuel source, she decided to learn more about these organisms’ potential to supply energy without using precious crop land.
Surveying gaps in current research, Sara decided to explore how growing conditions of algae might affect their oil yields. Sara received a 2011 Young Naturalist Award for her experiment, which she describes in her essay Enhancing Algae Biofuels: The Effects of Nitrogen Limitation and Carbon Dioxide Infusion on Nannochloropsis oculata.
Sara decided she would measure whether nitrogen limitation and carbon dioxide infusion could enhance algae growth and the amount of lipids produced. Though environmental “stresses” like a nitrogen deficit might slow overall growth rates, Sara hypothesized that some stresses might make algae a more efficient fuel source if they significantly increased lipid production.
Sara examined three groups of algal cultures: nitrogen-depleted cultures, carbon dioxide-infused cultures, and control cultures. She conducted the testing in a photobioreactor that she built. After testing, she measured the dry weight and lipid content of each of the cultures, and then divided the extracted lipid quantities by the original dry mass of the algae to get the relative amount of lipid per sample. By then multiplying the amount of lipid per sample with the overall amount of algae produced, she could estimate the oil yield and see whether the benefits of growing algae in these conditions outweighed any loss in biomass. Read more »
Friday, October 21 3:19 pm
Joshua collected water samples from Strawberry River in Arkansas to look for the presence of fecal contaminants. Photo courtesy of Joshua. Click to enlarge.
Seventeen-year-old Joshua had fond memories of swimming in Arkansas’s Strawberry River, a popular site for community gatherings and picnics. But after the construction of a wastewater treatment facility upstream, no one would enter the waters. “The wonderland where I spent so many hours as a child is deserted now, and nobody swims or fishes in that section of the river,” Joshua would later write. “I decided to find out for myself if the [facility] had indeed contaminated the water, or if the community had overreacted.”
Hypothesizing that the water was unsafe for swimming and wading due to contamination, Joshua tested the water in various sites along the river over the course of a year—a project that led to Joshua’s essay An Evaluation of Fecal Contamination in Strawberry River, for which he received a 2011 Young Naturalist Award.
Joshua evaluated the risk of water-related illness in the river by measuring the amounts of Escherichia coli in the water, as well as Enterococcus faecalis, intestinal microbes that can be harmful to humans. While E. coli testing can measure fecal pollution, E. faecalis is better at distinguishing between human and animal feces because it is found primarily in humans and chickens rather than in all warm-blooded animals. Joshua also took note of the climate, topography, land use, and potential animal fecal contaminators around Strawberry River in order to see the full picture of its apparent pollution. Read more »
Thursday, October 06 3:15 pm
Katelyn gets to know the subjects of her experiment. Photo courtesy of Katelyn. Click to enlarge.
When 12-year-old Katelyn took a field trip to a butterfly exhibit, she wondered why butterflies chose certain flowers over others when it came time to feed.
The question led Katelyn to conduct an experiment that tracked painted lady butterflies’ flower preferences. Her project, which earned her a 2011 Young Naturalist Award, is described in the essay Butterfly Buffet: The Feeding Preferences of Painted Ladies.
Katelyn hypothesized that butterflies given a choice of flowers would display a preference for certain colors or shapes. To test her idea, Katelyn set up elaborate mini-ecosystems, complete with various floral arrangements, and recorded each time a butterfly inserted its proboscis into a flower, paying special attention to whether butterflies returned to the same flower. Read more »
