Geographical and Biological History of Earth-2021

                         A short account on Geographical and Biological History of the Earth

Eons	Eras	Periods	Epochs of Cenozoic	Events in the history of life	Other important events (climate)
present	Present Cenozoic	Present Quaternary	Present Holocene           0.5 MY	Human cultures	Climatic zones and changes of season
		1.8 MY	Pleistocene           1.8 MY	Man in stone age, human as user of fire and tools	Periodic continental glaciers in north
			Pliocene           5.2 MY	Earliest man (2 MY)	Cool and temperature climates away from equator
		Tertiary	Miocene            24 MY	Rapid spread and development of grazing mammals, angiosperms	Cooling of climate
Phanerozoic			Oligocene            38 MY	Earliest elephants, first modern mammal	Warm climates still widely spread
			Eocene            54 MY	First rhinoceros and camels	Zoned climatic belts well established
	65 MY	65 MY	Paleocene            65 MY	First primates and horses, spread of mammal, birds and insects	Development of climatic bells
	Mesozoic	Cretaceous            145 MY		Extinction of dinosaurs, first flowering plants, spread of flowering plants, marsupial mammal	Birth of modern mountains development of climatic diversity
		Jurassic            190 MY		First bird and mammals, gymnosperms as dominating plants	Culmination of worldwide warm climate
	250 MY	Triassic            250 MY		The first dinosaurs (225 MY)	Worldwide tropical and subtropical climate
	Palaeozoic	Permian            280 MY		Mammal like reptiles	Ice age in southern hemisphere climates become varied.
		Pennsylvanian            325 MY		First reptiles, amphibians dominant on land, spread of coal plants	Uniform climates throughout world
		Mississipian            345 MY		Rise of insects Forest of coal plants	Uniform climate, spread of tropical seas
		Devonian            395 MY		First amphibians, First forest, first insects	Broad distribution of uniform climates, Increased temperature
		Silurian            430 MY		First air breathing animals, First land plants	Slight climate cooling
		Ordovician            500 MY		Trilobites at peak, First vertebrate (fish)	Wide spread flooding of north America by seas, Warm climate
570 MY	570 MY	Cambrian            570 MY		Marine shelled invertebrates common, First abundant animal fossils	Climate become progressively warmer
Proterozoic        2500 MY				Marine invertebrates probably common, few with shells (1200 MY)	Glaciation- probably worldwide
Archean       3800 MY Hadean				Earliest plants [ Marine algae ](3200 MY) The first life bacteria ( 3800 MY ago )	Oldest rock ( 3500 MY )