For Susan Finkbeiner, wearing rain boots to trudge around the University of Chicago campus was a familiar feeling.

After all, the 30-year-old scientist does fieldwork in the Amazon rain forest, trudging around in the rain a world away from Chicago.

That morning, she pulled on rain boots. But days earlier, she'd been striding in 6-inch heels. That's because she lives what she refers to as a double life — she is both a scientist at the University of Chicago studying tropical butterflies and a model who jets away for the weekend to walk on international runways.

"It's this crazy Cinderella story. One month, I'm literally knee-deep in mud and covered in rain and romping through the jungle," she said. "Five months later, I'm training to be a runway model."

In February, Finkbeiner walked for nine designers in two shows during London's Fashion Week. Leaving Chicago on a red-eye flight, she revised two research papers on the plane. At Heathrow, she grabbed a copy of BBC Focus Magazine that included an article she'd written.

After hours getting her hair and makeup done, she spent the afternoon and evening walking in multiple shows.

She said, "I'm used to being in front of crowds for speaking, at conferences and lecturing and that sort of thing, but this was so different. And I loved it because it was so different."

She said that during her fieldwork, walking rain forests throughout Ecuador, someone said she should consider modeling. At the time, she was at Boston University, where she worked as a researcher after getting her doctorate in ecology and evolutionary biology at the University of California, Irvine. She met with a modeling agency that began sending her to shows. "The modeling is something that's out-of-this-world fun," she said.

The day after her shows in London, she was back in her workspace at the Kronforst laboratory. There, the postdoctoral research scholar showed off Heliconius butterflies pinned in drawers, marveling at their beauty.

She has received grants and honors from the Smithsonian and National Science Foundation, and her research aims to understand animal evolution across geographic areas. Recently, she taped an interview for a PBS Nature episode "Sex, Lies and Butterflies" that will air in April.

At the university greenhouse, she explained the different types of live butterflies. Finkbeiner carefully captured one by gently folding its wings together, to show its patterns.

Ever since she was a child growing up in Rockford, Ill., she loved watching the Discovery Channel, which introduced her to science. And she loved bugs.

"I was obsessed with them," she said. "I always had jars full of bugs with me."

But she was told, "Bugs aren't a girl thing." She wants girls to know they can play in the dirt, study bugs and grow up to work with them. "No one should tell you what you should or shouldn't do," she said.

People don't have to be one thing or another, she said. And she hopes to be an example of how scientists aren't simply people who sit in a lab, and models aren't simply people who look pretty. She said, "I really enjoy being a scientist, but a part of me likes to enter other worlds if I can."