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Here, we also cover the 'Ordivician (488-444), the area north of the tropics was almost entirely ocean, and most of the world's land was collected into the southern supercontinent Gondwana. Gondwana finally settled on the South Pole when, massive glaciers formed, causing shallow seas to drain and sea levels to drop. This likely caused the mass extinctions that characterize the end of the Ordovician in which 60% of all marine invertebrate genera and 25% of all families went extinct. Was there are any life ON Gondwana?
Fungi in the Ordovician became associated with plants as shown by fossilized non-septate hyphae and spores of Glomalean-like fungi within bryophyte cells (Redecker et al. 2000).
First plants
First plants
The earliest evidence of plants dates back to around 460mya, during the Ordovician period. When building the Douglas Dam a ‘benchmark assemblage' of early plants and fungi were found. Much more on mosses
"The most "groundbreaking" occurrence of the Ordovician was the colonization of the land". It "witnessed the transition from a microbial terrestrial biota to one dominated by a vegetation of the most basal land plants. The oldest reported occurrence of cryptospores clearly related to land plants is currently considered to be in the Middle Ordovician (Dapingian or Darriwilian) suggesting that land plants had successfully invaded the land by this time. ....The first trilete spores appear in low numbers in the Ordovician.
"We have obtained a diverse trilete spore occurrence from the Late Ordovician that suggests that vascular plants originated and diversified earlier than previously hypothesized, in Gondwana, before migrating elsewhere and secondarily diversifying". (Steemans 2009). These two sorts of spores may be the direct ancestors of land plants because of their size, gross morphology, and wall structure. They are also later associated in the geologic record with definite land plants. "444mya the evolution of land plants increased depth and intensity of weathering" (Retallack 2013)
"At the same time non-marine aquatic biotas began to increase in diversity, although it seems that the only animals on the land were probably temporary visitors that were not obligate subaerial dwellers." (Wellman 2022)
The mixing of bacteria, protozoans, fungi, and plant parts created a totally new environment but there was no real soil structure. There would have been the raindrops and the smell of the earth we know today. They are formed when bacteria are producing spores in the damp conditions.
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