Fungal Fusion

Plant-it Earth

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The Plant and Fungi Kingdoms evolve on land so closely together in time that we are unclear which of the two came first. The fungal fusion hypothesis opts for neither, suggesting a joint venture. It proposes that fungi and landward photosynthetic algal symbionts joined together to evolve the capability to survive dryness. Was it just a joint venture or did it go further?

Perhaps land plants arose through both a somatic (body) and permanent fusion of fungi with algae. This symbiogenesis is much like the "horizontal" gene transfer which bacteria practice.

Life on land poses far different demands that did life in the sea. Life-forms develop "hypersea" -- the movement of sea water onto land, but inside organisms.

"Redwood trees, wasps and other organisms visible to the unaided eye are habitats of rich ecosystems of much smaller organisms that cover their surfaces, probe their interstices, take up residence in body cavities, and invade (sometimes peacefully, sometimes not) even the inner sanctum of their cells."

Mark McMenamin, Hypersea

How many ecosystems are within this ecosystem? (Photograph courtesy JASON Foundation for Education)