Prof’s Study Shows Worms Like It Hot

A Harvard researcher has unearthed new evidence in the quest to explain how life can thrive under extreme conditions.

In a report published in last week’s issue of Science, Assistant Professor of Organismic and Evolutionary Biology Peter Girguis shed new light on the resiliency of the basic building blocks of life, by studying the behavior of worms that live in thermal vents at the bottom of the ocean.

“These worms have been able to feed, reproduce, and live in a niche that no other animal has been able to,” Girguis said. “What a great adaptation.”

The findings help scientists understand the limits to which the chemical structures common to all animals can be pushed.

The worms, known as Paralvinella sulfincola, can withstand conditions where water pressure reaches 4,000 psi and temperatures can change from 2 degrees to 350 degrees over a few millimeters.

Girguis and his team recreated this temperature gradient on a smaller scale in their lab, constructing a tank of water that was cold on one end and hot on the other. Worms were then scattered randomly across the tank.

Instead of standing still, as Girguis had expected them to, the worms all migrated to the region of the water that was roughly 50 degrees Celsius. This effectively mapped out the temperature range the organisms could tolerate, according to Girguis.

The worms’ natural habitat is “as hot as the hottest deserts on Earth,” Girguis said. Because water conducts heat so well and because worms are unable to regulate their internal body temperature, their insides are exposed to the full brunt of the temperature, he said.

“It’s really interesting to see life try to push the envelope,” Girguis said.