Evolution of Earth: first fungi? (Evolution)

by David Turell , Friday, May 31, 2019, 15:00 (2001 days ago) @ David Turell

Newly found fungi fossils support a theory that early fungi helped start plants on land:

https://theconversation.com/complex-life-may-only-exist-because-of-millions-of-years-of...

"Extracted from Arctic Canadian shales, the newly discovered billion-year-old fossilised fungal spores and hyphae (long thin tubes) plug the gap in the fossil record and suggest that fungi may have occupied land well before plants.

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"As you might imagine from their ancient origins, fungi have played a critical role in shaping Earth’s terrestrial biosphere over the last billion years. The first plants to emerge onto land 500m years ago formed intimate partnerships with fungi. Lacking roots, these early plants relied on their fungal partners to grow inside them and spread outwards into the primordial mineral soil. In a process known as biological weathering, fungal hyphae would secrete organic acids to dissolve rocks and extract nutrients held within. In return, the plants would transfer nutrients produced through photosynthesis to the fungi.

"This exchange of resources between early plants and fungi powered the growth, evolution and diversification of Earth’s flora into ever more complex species, communities and ecosystems, and remains the norm today. Over 90% of land plants associate with a fungal partner of one type or another, and some are entirely dependent on fungal assistance to survive.

"The symbiotic rise of land plants and their fungal partners also had dramatic effects on our atmosphere. Now with abundant access to mineral-based energy building blocks, plants evolved more efficient mechanisms for photosynthesis to capture this energy, for example through better control of the movement of carbon dioxide and water into and out of leaves. Over millions of years, this increased absorption of carbon dioxide produced a massive rise in oxygen concentrations, supporting the emergence of much larger, more complex animal life than the tiny insect-like life forms that previous oxygen levels could support.

"From there, the evolutionary story is clear. But in showing that fungi probably arrived on land 500m years before plants, the new fossil evidence raises fundamental questions about the start of this symbiotic journey.

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"... the new discovery opens up the possibility that Earth’s lands may have been already being prepared for successful plant life for hundreds of millions of years. Dissolving mineral-rich rocks and secreting carbon-based organic acids, we know that fungi were extremely important in converting barren lands into the fertile, carbon-rich soils we know today. It could be that the emergence of plant life was only made possible by aeons of groundwork by ancient fungal forefathers.

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"What is already clear is that without fungi, we would not exist. Playing a vital role in the maintenance of healthy ecosystems across the planet, from the Antarctic deserts to the tropical rainforests, fungi underpin all life on Earth today. Now, it appears we may have another 500m years to thank them for."

Comment: A clear example of how the Earth evolved to support life. God creates by evolution: the universe, the Earth and life are certain examples.