It’s lean, green and a long-living machine.
Because the seagrass Posidonia oceanica generates clones of itself, a single organism has been found to span 15 kilometres, weigh more than 6000 tonnes and may well be more than 100,000 years old.
An international research team involving the University of Western Australia is probing this Methusela of all organisms.
“Clonal organisms [such as the Posidonia oceanica] have an extraordinary capacity to transmit only highly competent genomes, through generations, with potentially no end,” director of UWA’s Oceans’ Institute Carlos Duarte said.
Researchers have analysed 40 meadows of the seagrass across 3500 kilometres of the Mediterranean sea.
Computer models helped demonstrate that Posidonia oceanica which – like all other seagrasses can reproduce both sexually and asexually – can spread and maintain clones over millennia.
“Understanding why those particular genomes have been so adaptable to a broad range of environmental conditions for so long is the key to some interesting future research,” Professor Duarte said.
Seagrasses are the foundation of important coastal ecosystems but have waned globally for the past 20 years.
Posidonia oceanica meadows are now declining at an estimated rate of five per cent annually.
“The concern is that, while Posidonia oceanica meadows have thrived for millennia, their current decline suggests they may no longer be able to adapt to the unprecedented rate of global climate change,” Professor Duarte said.
The genus Posidonia occurs only in Australian and Mediterranean waters.