Scientists uncover early Earth mysteries

The research, which was published yesterday in Nature Communications, has provided missing evidence showing that an ancient plant group worked together with soil-dwelling fungi to "green" the Earth in the early Palaeozoic era, nearly half a billion years ago.

In carrying out their study, academics from Sheffield worked with experts from the Royal Botanic Gardens at Kew, Imperial College London and the University of Sydney.

Until now there has been a lack of evidence demonstrating if and how the earliest ancient land plants from the early Palaeozoic era might have cooperated with fungi to colonise the Earth.

The researchers studied a thalloid liverwort plant, a member of the most ancient group of land plants that still exists, and used controlled-environment growth rooms to simulate a carbon dioxide-rich atmosphere similar to that of the Palaeozoic era when these plants originated.

The team found that the plants grow and reproduce better when colonised by fungi because the fungi provides essential soil nutrients. In return, the fungi also benefits by receiving carbon from the plants. Professor David Beerling, from Sheffield University's department of animal and plant sciences, said: "By studying these ancient plants we open a window on the past to investigate how the earliest land plants evolved. Our results support the idea that the 'greening' of the Earth was promoted by a symbiosis between plants and fungi.

"It shows that plants didn't get a toe-hold on land without teaming up with fungi – this has long been suspected, but until now not investigated. It will require us to think again about the crucial role of cooperation between organisms that drove fundamental changes in the ecology of our planet."