Nature in Revolt
Student finds earth conditions very real in Biosphere 2.
Cockroaches, they say, will outlast the human race. In the meantime, the hearty buggers manage to find ways to wreak havoc even when humans think they have the upper hand.
U of L biology student Natalie Abram found that out recently when she was conducting a global warming-related experiment in the controlled-climate environment of the Columbia University Biosphere 2 research center in Oracle, Ariz. While there, she also attended classes and conducted field work.
During Abram's four-month study, cockroaches sneaked into an enclosed research area and ate some of the plants she was using in her experiment. To make matters worse, carbon dioxide (CO2) had leaked from a hose and corrupted some of the data, which had to be thrown out.
"For three-quarters of the semester we had problems," Abram says. "But we did obtain six days' worth of usable data in the last week. That's what happens in science sometimes. Sometimes you have to start over."
After constructing a moat of sorts to keep out the roaches, Abram resumed her experiment. She was able to test a hypothesis and salvage promising data that could lead to further studies.
It also gave Abram a chance that few biology students have: to work in the famous biosphere as a research assistant to respected biologist and chemist Leif Abrell.
Abram wanted to see if the egg-laying behavior of moths was affected by elevated CO2.
As pollution and natural sources cause carbon dioxide to increase in the atmosphere, scientists worry that the resulting climate change could lead to declining plant and animal populations.
Many insects including the moth Manduca sexta (tobacco hornworm or hawk moth) can sense CO2, but how this works remains a mystery.
The moths prefer to lay their eggs on the leaf of the Jimson weed, a perennial common in the arid American Southwest. At the pupal stage, the developing moths feed on the leaf's underside.
Abram wanted to see if the egg-laying moths would avoid plants exposed to higher concentrations of CO2 and favor those in more normal, oxygen-enriched environments.
"I wanted to find out if plants in the CO2-enriched environment would throw off the homing devices of the moths so that they wouldn't know where to lay their eggs," she says.
How the moths behaved in a controlled environment might provide clues as to how they would behave in the outside world.
Abram found that the moths laid their eggs on both the CO2-enriched and oxygen-enriched plants, but that overall they favored the oxygen-enriched ones.
"I think it's important to understand what kinds of biological functions might be affected by rising CO2 in our environment," Abram adds. "It was really nice to have the chance to be able to study these questions in the biosphere."
