Last year microbial ecologist Noah Fierer, now at the University of Colorado at Boulder, sampled bacterial diversity in 98 different soils across North and South America.
It's too soon to say that the microorganisms found at 16 meters are in fact 2800 years old, since the ice could have melted and refrozen recently, says microbialecologist Warwick Vincent of the University of Laval in Quebec City, Canada.