Free-floating Antarctic icebergs significantly change the marine ecosystems directly around them by hosting land-based matter, chlorophyll, krill and seabirds, according to a report in this week's Science. Researchers detected these organic travelers hanging out in surrounding waters as far as 2.5 miles from their frigid base camp. The iceberg ecosystems, which both capture and release carbon, will likely grow in number as the planet warms, the group says.