The largest fungi ever to exist on Earth lived during the Devonian. They were giant towers that could grow up to eight metres in height and one metre in width. Their name is Prototaxites and you can see models of them on the floor behind you.
Prototaxites fossils look like tree trunks, and their exact nature has long been uncertain. Some scientists believe they were enormous lichens, others that they were algae or liverworts. But most indications are that they were fungi that grew among the less imposing green plants of the Devonian Period.
It has not been determined how they took up nutrients. But it is certain that these giant fungi were the largest land-dwelling organisms of their time.
Giant fungus Prototaxites.
Image: Mary Parrish.