What do you believe is the single most important factor driving up the cost of living in Nigeria?

The ocean's twilight zone is deep, dark, and—according to new research—iron deficient. No sunlight reaches this region 200 to 1,000 meters below the sea surface, where levels of iron, a key micronutrient, are so low that the growth of bacteria is restricted. To compensate, these bacteria produce molecules called siderophores, which help the bacteria scavenge trace amounts of iron from the surrounding seawater.

A Nature paper detailing these unexpected findings from the Pacific Ocean could change the way scientists view microbial processes in the deep ocean and offer new insight into the ocean's capacity to absorb carbon.

"Understanding the organisms that facilitate carbon uptake in the ocean is important for understanding the impacts of climate change," said Tim Conway, associate professor of chemical oceanography at the USF College of Marine Science, who co-authored the recent study.

"When organic matter from the surface ocean descends to the deep ocean, it acts as a biological pump that removes carbon from the atmosphere and stores it in seawater and sediments. Measuring the rates and processes that influence this pump gives us insight into how and where the ocean stores carbon."

Co-chief Scientist Phoebe Lam of the University of California, Santa Cruz and others removed the pump's damaged section of cable from the winch. Credit: Alex Fox

• Read More