City-sized sea meadow is world’s biggest plant

Are plants the real masters of Earth? An ancient self-cloning weed discovered off the coast of Australia seems to prove that they can thrive despite immense environmental change. Off the coast of Australia there is a huge underwater meadow. Big-nosed animals called dugongs eat the seagrass that stretches into the distance. Now scientists have made a discovery about this environment. Most of the grass is actually a single plant. It is 200 square kilometres – roughly the size of Glasgow. The plant is 4,500 years old. It is now thought to be the largest plant in the world. Scientists say the plant has survived so long because it is a mixture of two different species. This is an especially amazing plant. But plants in general are a very successful form of life. In 2016 scientists conducted a “census” of all life on Earth. They estimated plants accounted for 80% of the weight of all life on Earth. Bacteria made up 15%. All animals (including us) made up less than 0.5%. Some say that animals are Earth’s dominant life form because of our intelligence. But some scientists are also questioning this as well. Plants are thought to have between 15 and 20 senses. These include senses similar to sight, smell and even hearing. They can also change their behaviour, for instance by deciding where to grow and what chemicals to produce. One plant curls its leaves in response to threat. Experiments suggest that it “remembers” earlier threats for longer than some animals. Plant behaviour happens much slower than animal behaviour and it is often invisible. But botanists like Stefano Mancuso say that plants are "intelligent". Other scientists disagree, arguing that intelligence cannot exist without brains.  There is no doubt that plants have the advantage in one important way. “If we were to vanish tomorrow, the plants would be fine” Mancuso says, “but if the plants vanished… ” Are plants the real masters of Earth?  Green planet Yes: Our animal-centric arrogance has blinded us to the genius of plants. They have transformed the surface of the Earth more drastically than we ever will, and they’ll be here long after we are gone. No: Plants might have the numbers on their side, but nothing else in nature compares to the complexity of the brain. Animals are the true pinnacles of evolution, and humans most of all. Or... If developments in plant science can teach us anything, it’s that life on Earth is not just a competition between opposing life forms. Animals, plants and humans ourselves are all part of one great system.   KeywordsLargest plant - By surface area, at least. A group of aspen trees that share a root system in Utah, USA is larger in terms of its overall mass.