The world's largest known plant has been discovered off the coast of Western Australia.
The plant, a seagrass, is 180 km (111 miles) long and thought to be around 4,500 years old.
Researchers, from the University of Western Australia and Flinders University, said they were blown away by the discovery when they realised what they initially thought was a large underwater meadow was in fact just one plant.
Scientists think it spread from a single seed.
Evolutionary biologist, Dr Elizabeth Sinclair, said the project began when researchers wanted to understand how genetically diverse the seagrass meadows in Shark Bay were, and which plants should be collected for seagrass restoration.
“We often get asked how many different plants are growing in seagrass meadows and this time we used genetic tools to answer it,” Dr Sinclair said.
Jane Edgeloe, lead author of the study, said the team sampled seagrass shoots from across Shark Bay and generated a ‘fingerprint’ using 18,000 genetic markers.
“The answer blew us away – there was just one!” Ms Edgeloe said.
“That’s it, just one plant has expanded over 180km in Shark Bay, making it the largest known plant on earth.
“The existing 200km2 of ribbon weed meadows appear to have expanded from a single, colonising seedling.”
The researchers have now set up a series of experiments in Shark Bay to understand how this plant survives and thrives under such differing conditions underwater.
Dr Sinclair added: “Even without successful flowering and seed production, it appears to be really resilient, experiencing a wide range of temperatures and salinities plus extreme high light conditions, which together would typically be highly stressful for most plants.”
The research has been published in the journal Proceedings of the Royal Society B.
