Changes

Several million years ago, a species of small African ape gained the ability to stand upright.<ref>{{cite book |last=Margulis |first=Lynn |coauthors=Dorian Sagan |year=1995 |title=What is Life? |publisher=Simon & Schuster |location=New York |id=ISBN 0-684-81326-2}} The subsequent advent of human life, and the development of agriculture and further [[civilization]] allowed humans to affect the Earth more rapidly than any previous life form, affecting both the nature and quantity of other organisms as well as global climate. (By comparison, the [[Oxygen Catastrophe]], produced by the proliferation of algae during the [[Siderian]] period, required about 300 million years to culminate.)

Several million years ago, a species of small African ape gained the ability to stand upright.<ref>{{cite book |last=Margulis |first=Lynn |coauthors=Dorian Sagan |year=1995 |title=What is Life? |publisher=Simon & Schuster |location=New York |id=ISBN 0-684-81326-2}} The subsequent advent of human life, and the development of agriculture and further [[civilization]] allowed humans to affect the Earth more rapidly than any previous life form, affecting both the nature and quantity of other organisms as well as global climate. (By comparison, the [[Oxygen Catastrophe]], produced by the proliferation of algae during the [[Siderian]] period, required about 300 million years to culminate.)

The present era is classified as part of a mass extinction event, the [[Holocene extinction event]], the fastest ever to have occurred. Some, such as [[E. O. Wilson]] of [[Harvard University]], predict that human destruction of the [[biosphere]] could cause the extinction of one-half of all species in the next 100 years. "The mid-Holocene extinction of silver fir ''(Abies alba)'' in the ..." [http://www.springerlink.com/index/D85T53513002564V.pdf] The extent of the current extinction event is still being researched, debated and calculated by biologists.(See, e.g. [http://park.org/Canada/Museum/extinction/holmass.html], [http://park.org/Canada/Museum/extinction/extincmenu.html], [http://park.org/Canada/Museum/extinction/patterns.html])

The present era is classified as part of a mass extinction event, the [[Holocene extinction event]], the fastest ever to have occurred. Some, such as [[E. O. Wilson]] of [[Harvard University]], predict that human destruction of the [[biosphere]] could cause the extinction of one-half of all species in the next 100 years. [http://www.springerlink.com/index/D85T53513002564V.pdf] The extent of the current extinction event is still being researched, debated and calculated by biologists.(See, e.g. [http://park.org/Canada/Museum/extinction/holmass.html], [http://park.org/Canada/Museum/extinction/extincmenu.html], [http://park.org/Canada/Museum/extinction/patterns.html])

===Atmosphere, climate and weather===

===Atmosphere, climate and weather===