For 150 years, biologists have believed that lichens were a co-operation between a fungi and a microscopic algae — a symbiosis of two organisms. But over all that time, scientists have been unable to grow lichens in laboratories.
Recently, a researcher called Toby Spribille discovered the reason — there are not two, but three partners. ‘We now see that they require two different kinds of fungi and an algal species. If the right combination meet together on a rock or a twig, then a lichen will form, and this will result in the large and complex plant-like organisms we see on trees and rocks very commonly.’
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