Middle school dating timeline

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The end-Frasnian extinction was most pronounced in tropical environments, particularly in the reefs of the shallow seas.

Reef building sponges called stromatoporoids and corals suffered losses and stromatoporoids finally disappeared in the third extinction near the end of the Devonian.

All of the major animal groups of the Ordovician oceans survived, including trilobites, "When I view all beings not as special creations, but as the lineal descendants of some few beings which lived long before the first bed of the Silurian system was deposited, they seem to me to become ennobled.

Judging from the past we may safely infer that not one living species will transmit its unaltered likeness to distant futurity." (Charles Darwin) From primal swamp to speaking humans: Ernst Haeckel said (1903) that the Pithecoiden (monkey) theory of human evolution requires tracing our animal ancestors before monkeys.

Three strata of toadstone had been found, and the limestone under the third was as far as miners had reached. The map project describes the "shallow tropical sea surrounded by coral reefs" in which the limestones were laid down and how "subterranean volcanoes erupted spasmodically through the sea floor, covering the limestones with ash and lava" which formed the toadstone.

is Galena (lead sulfide) formed as pockets or veins in carbonate rock into which the mineral bearing fluid rock has intruded.

"In all but detail, this fossil is indistinguishable from modern Bangia" for the Ediacaran fossils to first appear, 655,000,000 years ago. This showed life beginning with the Silurian system, which it described as "a marine deposit of vast extent containing abundance of marine organic remains. Together, these extinctions may have removed about 85 percent of species of marine animals.They said "the epithet carboniferous is of obvious application to this series".Henry Shaler Williams (1891) proposed Pennine System as the name for the Carboniferous.) 13,800,000,000 (13.8 billion) years ago The creation of the universe according to present estimates of "big bang" - "Stephen Hawkings and others...estimate between 18 and 11 billion with 13.8 being the closest estimation".

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