Climate Change Threatening to Kill Oldest Living Things on the Planet

A seagrass meadow in Florida. Photo courtesy: Heather Dine / NOAA Photo Library/CC BY 2.0

It's survived for possibly hundreds of thousands of years, spreading across the bottom of the Mediterranean Sea. But now, what is thought to be the oldest living thing on Earth may be reaching the end of its extended lifespan -- due to climate change.

According to research published earlier this month in PLoS ONE, the journal of the Public Library of Science, the vast meadow of the slow-growing seagrass Posidonia oceanica stretching underwater from Spain to Cyprus (h/t Boing Boing) could be up to 200,000 years old -- dating it back to the time when humans first appeared on the planet.

(The seagrass bed, which spans more than 2,000 miles, is what is known as a "clonal plant colony" and is identified by scientists as one single organism, constantly reproducing by cloning itself.)

Not just important because of its age alone, the Posidonia oceanica meadow, like other seagrass beds, supports "marine ecosystems that rank among the most valuable on earth in terms of biodiversity and production," the researchers wrote. Though the endemic Mediterranean seagrass has no native competitors or major predators, they said, it's not in good shape.

"The seagrass in the Mediterranean is already in clear decline due to shoreline construction and declining water quality and this decline has been exacerbated by climate change," Professor Carlos Duarte, a member of the research team, told The Daily Telegraph. "If climate change continues, the outlook for this species is very bad."