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Float Plan

Rachel Stevens, biology major

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Rachel Stevens hadn’t exactly charted out her course. She just knew that it started at the College – from there, she figured, she could map out her path to a degree in marine biology.

“But once I got here, I started thinking maybe that’s not what I wanted to study,” says the senior from Cape St. Claire, Md. “I got really interested in terrestrial plants. I was floating away from marine biology.”

So, hoping for a little direction, Stevens reached out to Jack DiTullio, a biology professor whose main research focus involves marine phytoplankton.

“That piqued my interest, because I really respect the ecological role that phytoplankton plays, and – as ‘plants’ of the ocean – they make for a perfect merge of my interests,” says Stevens.

Impressed by Stevens’ dedication to her studies, DiTullio asked her to join his research cruise to Iceland – he could tell she had just the tireless work ethic necessary for the conditions of the ship. And so, a few months later, she was chasing phytoplankton blooms with DiTullio’s research team and other scientists interested in coccolithophores like Emiliania huxleyi, or Ehux.

“It was really cool just to be among such an esteemed group of people,” says Stevens. “These scientists are the celebrities of the Ehux world – many have written seminal papers that have been so important to the progression of understanding these little guys.”

And – as one of only two undergraduate students on last summer’s cruise– Stevens aimed to push that understanding even further. What she and the rest of the DiTullio team in particular wanted to know was how and why Ehux produces a compound called DMSP. When the Ehux is eaten by zooplankton, DMSP turns into DMS, which is released into the atmosphere and helps clouds form. Because the Ehux is not susceptible to viruses in warm water, they are eaten by zooplankton, which causes more clouds to form, which cools the water.

“It’s a Gaia cycle,” says Stevens, explaining that, according to the Gaia Theory, when there is an imbalance in the Earth, the planet fixes itself. “It’s almost spiritual to me. It really is awe inspiring.”

It’s that inspired attitude that DiTullio says Stevens contributed to the research cruise – along with her long hours of filtering samples and performing dilution experiments to test the differences in Ehux mortality rates caused by grazing zooplankton versus viral infections.

“Rachel had a very strong influence in helping make our expedition successful,” he says. “Several senior investigators commented on how her positive outlook and exuberance on oceanographic research was invigorating and contagious.”

Between the endless skies, the pilot whales and the stimulating conversation, Stevens says it was hard not to be enthusiastic or find a new perspective of the world and her place within it.

“I was always sizing up the globe when I was out there,” she says. “Looking at the satellite and seeing your path going from country to country, it appears really small. But when it takes two days to get from Point A to Point B, it seems really, really big. If you look at our path, we were all over the place!”

Still, Stevens feels less lost now than she did before her expedition into the North Atlantic – she knows it’s OK to get a little off course every now and then. As for her own plan – she is joining DiTullio’s research team again in February, this time to study the phytoplankton in the Ross Sea of Antarctica.

“I’m honored to be part of the lab again. It just goes to show how far you can go when you work hard at whatever you are doing – even if you are not sure it’s what you want to do for the rest of your life. You never know where it might take you,” she smiles. “And so my journey continues!”

Indeed, Stevens might not have everything mapped out quite yet, but she is right on course.