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Little is known about the paleogeography before the formation of Rodinia. Paleomagnetic and geologic data are only definite enough to form reconstructions from the breakup of Rodinia [17] onwards. Rodinia is considered to have formed between 1.3 and 1.23 Ga and broke up again before 750 Ma. [18] Rodinia was surrounded by the superocean Mirovia.
Rodinia formed after the breakup of the supercontinent Columbia and prior to the assemblage of the supercontinent Gondwana (~500 Ma). [19] The defining orogenic event associated with the formation of Gondwana was the collision of Africa, South America, Antarctica and Australia forming the Pan-African orogeny .
A tree of life, like this one from Charles Darwin's notebooks c. July 1837, implies a single common ancestor at its root (labelled "1"). A phylogenetic tree directly portrays the idea of evolution by descent from a single ancestor. [3] An early tree of life was sketched by Jean-Baptiste Lamarck in his Philosophie zoologique in 1809.
Recognizable humans emerged at most 2 million years ago, a vanishingly small period on the geological scale. The earliest undisputed evidence of life on Earth dates at least from 3.5 billion years ago, [7] [8] [9] during the Eoarchean Era, after a geological crust started to solidify following the earlier molten Hadean eon.
Bacteria are prokaryotic microorganisms that can either have a bacilli, spirilli, or cocci shape and measure between 0.5-20 micrometers. They were one of the first living cells to evolve [9] and have spread to inhabit a variety of different habitats including hydrothermal vents, glacial rocks, and other organisms.
The supercontinent, known as Rodinia, broke up around 750 Ma. A number of glacial periods have been identified going as far back as the Huronian epoch, roughly 2400–2100 Ma. One of the best studied is the Sturtian-Varangian glaciation, around 850–635 Ma, which may have brought glacial conditions all the way to the equator, resulting in a ...
As creatures like Paramecium, Amoeba and Melanocyrillium appear, first animal-like cells become distinctive from plants – rise of herbivores in the food chain. Breakup of Rodinia , Sturtian glaciation begins, one of at least three episodes of Snowball Earth – great ice sheets cover most of planet stunting evolution of animal and plant life ...
c. 750 Ma – First Protozoa appears: as creatures like Paramecium, Amoeba and Melanocyrillium evolve, first animal-like cells become distinctive from plants – rise of herbivores (plant feeders) in the food chain. First Sponge-like animal: similar to early colonial foraminiferan Horodyskia, earliest ancestors of Sponges were colonial cells ...