A team of scientists melted five samples of ice from Antarctica in hopes of reviving the oldest known frozen bacteria—millions of years older than any previously brought to life. And, in fact, the bacteria, ranging in age from 100,000 to a stunning 8 million years old, came groaning back in the culture flask. The younger the bacteria, the more quickly the resurrection occurred. It took the younger bacteria just seven days to reproduce; the oldest samples took up to 10 times as long.

The finding could have a profound effect on microbial life. As Antarctic ice melts, the bacteria frozen inside may revive and be taken up by microbes in the ocean, says Paul Falkowski, a Rutgers University biologist who directed the bacteria project.

“We are watching gene transfer from land into the ocean, introducing something completely different from the last millions of years,” Falkowski says. He points out that humans, through global warming, are subtly bringing about a new phase of evolution. While the evolution probably won’t have a direct effect on humans, Falkowski believes that it could lead to a change in this minuscule variety of marine life. It is important that genomes in the ocean be recorded as they are now, Falkowski says, because the coming change could happen quickly. “We are potentially on the cusp of a global revolutionary experiment in the microbial world,” he says. “These evolutionary changes could be visible 50 to 100 years from now, showing us new genomes of marine organisms.”