The world's oldest living organism may not be that 43,000 year-old Tasmanian plant after all.

Scientists have discovered giant patches of seagrass in the Mediterranean Sea that are thought to be up to 200,000-years-old, United Press International reports.

The researchers determined the age of the seaweed patches using DNA sequencing at 40 different sites over a span of 2,000 miles, from Spain to Cyprus, according to New Scientist magazine.

The study, published in the journal PLoS One, showed the organisms ranged from 12,000 years to 200,000-years-old, with most of them likely being around 100,000-years-old.

Weighing 6,000 tons and stretching for 10 miles, the seagrass patches reproduce asexually and spread very slowly, eventually covering large areas. A key attribute to their longevity is their ability to store nutrients in their long branches, Professor Carlos Duarte from the University of Western Australia told the Telegraph.

Despite the organism's ability to survive in harsh conditions, scientists believe the seagrass is nevertheless declining, something scientists blame on global climate change.



"If climate change continues, the outlook for this species is very bad," Professor Duarte told the Telegraph. "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."