With the molecular biology revolution well underway, it’s easy to forget that science is still sometimes done the old-fashioned way: in the field, with a few hand tools, a sharp eye, and a really big gun, to protect yourself from hungry polar bears.

That’s a day in the life of Farish Jenkins, zoology professor at Harvard and the curator of mammology and vertebrate paleontology at Harvard’s Museum of Comparative Zoology. He gave a fascinating talk last night about his five-year search way up north in the Canadian Arctic for fish fossils that fill in a crucial gap in natural history: fossils showing how fish evolved into limbed vertebrates 385 to 359 million years ago.

That search culminated in a Nature paper that you might remember hearing about in the news last year: fossils of fish with eyes on top of its head, necks, shoulders and legs capable of propping up and propelling the fish on shore.

Jenkins told a room full of Boston-area science writers the back story of how he and his colleagues braved bitterly cold, sometimes gale-force winds on Ellesmere Island, took the risk of being eaten by polar bears and survived on crackers, candy bars to chip away at rocks during the short summer of 1999, 2000, 2002 and 2004 looking for fossils.

They brought fossils encased in rock back to their labs in August of 2004 and began the slow and painstaking process of separating rock from bone. They realized by October or November of that year that they had found something significant. They named the creature Tiktaalik roseae. Tiktaalik is the Inuit word for a large freshwater fish seen in shallow water (a homage to the Inuit that allowed the scientists onto their land). Roseae comes from Rose, the first name of the mysterious, wealthy woman who helps finance these expeditions, which cost up to $500,000 each.

At the end of the 2004 expedition, the scientists were wandering around camp waiting for the helicopter to come pick them up. They stumbled across polar bear prints not too far from camp. And they were massive. The bear apparently walked right by them. Farish made a cast of the paw print and keeps it in his office, reminding him of how lucky he was to escape attack. Goes to show to what extremes some scientists will go to do their work.

Farish and his collaborators are going back next year to continue their search.