Bunbury-born University of WA PhD student Jane Edgeloe discovers the biggest plant in the world in Shark Bay

Bunbury-born PhD student Jane Edgeloe was researching seagrass in Shark Bay when she discovered something incredible — the biggest plant in the world. The University of Western Australia researcher was looking into why the sea grass in the area was persisting in one of the most hostile environments in the world when she realised the samples she had taken from Shark Bay’s eastern and western gulfs actually came from one 180km long plant. The incredible Posidonia australis is located in the shallows of Shark Bay and is estimated to be at least 4500 years old. “(In 2019) I went out and collected all the samples and started the genetic analyses,” she said. “We had to analyse the data for a while and do lots of extra testing because the results we kept getting, we didn’t believe. “We thought, ‘this can’t be true’. “We did all the extra tests . . . and that confirmed it was the biggest plant on the planet.” Ms Edgeloe said the plant grew in patches across the vast stretch of shallows in Shark Bay. “It doesn’t grow continuously, obviously there is patches,” she said. “But we sampled multiple patches in this study and in other studies and we found it is one, it is one genetically identical individual.” The former Bunbury Cathedral Grammar School student started studying a Bachelor of Science in Marine and Environmental Science at UWA in 2016, before beginning her Masters of Marine Biology and is now completing a PHD of Marine Biology. Ms Edgeloe submitted her research paper in March and it was released on Wednesday with the discovery making international news — featuring in The New York Times and on the National History Museum website. Scientists are now trying to work out how the plant survives and thrives under such variable conditions. Ms Edgeloe said she expected the plant to continue to flourish despite the world’s changing climate, with it already having survived a “horrific” 2011 marine heatwave when temperatures in Shark Bay were between 2C and 5C warmer than average for two months. “We think that this massive plant actually will do OK in the face of climate change because it is a hybrid,” she said. “It has got double the number of chromosomes and it is a merge of two genomes. “Unless a massive event happens, I think it will go OK, but nevertheless, climate change will possibly affect it and we are testing that with other experiments at the moment.”