Editing Phanerozoic (section)

====Quaternary Period====
{{Main|Quaternary}}
[[File:Ice age fauna of northern Spain - Mauricio Antón.jpg|thumb|Megafauna of the Pleistocene ([[mammoth]]s, [[Panthera leo spelaea|cave lions]], [[woolly rhino]]s, [[reindeer]], [[Wild horse|horse]]s)]]
The Quaternary spans from 2.58&nbsp;million years ago to present day, and is the shortest geological period in the [[Phanerozoic Eon]]. It features modern animals, and dramatic changes in the climate. It is divided into two epochs: the [[Pleistocene]] and the [[Holocene]].

The Pleistocene lasted from 2.58 million to 11,700 years ago. This epoch was marked by a series of [[glacial period]]s ([[ice age]]s) as a result of the cooling trend that started in the mid-Eocene. There were numerous separate glaciation periods marked by the advance of ice caps as far south as 40 degrees N latitude in mountainous areas. Meanwhile, Africa experienced a trend of desiccation which resulted in the creation of the Sahara, [[Namib]] and [[Kalahari]] deserts. [[Mammoth]]s, [[giant ground sloths]], [[dire wolves]], [[sabre-toothed cat]]s and [[archaic humans]] such as ''[[Homo erectus]]'' were common and widespread during the Pleistocene. A more [[anatomically modern human]], ''[[Homo sapiens]]'', began [[early human migrations|migrating]] [[recent African origin of modern humans|out of East Africa]] in at least two waves, the first being as early as 270,000 years ago. After [[Toba catastrophe theory|a supervolcano eruption in Sumatra]] 74,000 years ago caused a global [[population bottleneck]] of humans, [[Southern Dispersal|a second wave of ''Homo sapiens '' migration]] successfully repopulated every continent except Antarctica. As the Pleistocene drew to a close, [[Quaternary extinction event|a major extinction]] wiped out much of the world's [[megafauna]], including non-''Homo sapiens'' human species such as ''[[Homo neanderthalensis]]'' and ''[[Homo floresiensis]]''. All the continents were affected, but Africa was impacted to a lesser extent and retained many large animals such as elephants, [[rhinoceros]] and [[hippopotamus]]. The extent to which ''Homo sapiens'' were involved in this megafaunal extinction is debated.<ref>{{cite web|url=http://www.ucmp.berkeley.edu/quaternary/pleistocene.php|title=Pleistocene|author=University of California|work=University of California|url-status=dead|archive-url=https://web.archive.org/web/20140824111711/http://www.ucmp.berkeley.edu/quaternary/pleistocene.php|archive-date=24 August 2014|access-date=27 April 2015}}</ref>

The Holocene began 11,700 years ago at the end of [[Younger Dryas]] and lasts until the present day. All [[recorded history]] and so-called "[[human history]]" lies within the boundaries of the Holocene epoch.<ref>{{cite web|url=http://www.ucmp.berkeley.edu/quaternary/holocene.php|title=Holocene|author=University of California|work=University of California|url-status=live|archive-url=https://web.archive.org/web/20150502160331/http://www.ucmp.berkeley.edu/quaternary/holocene.php|archive-date=2 May 2015}}</ref> Human activity is blamed for [[Holocene extinction|an ongoing mass extinction]] that began roughly 10,000 years ago, though the species becoming extinct have only been recorded since the [[Industrial Revolution]]. This is sometimes referred to as the "[[Sixth Extinction]]" with hundreds of species gone extinct due to human activities such as [[overhunting]], [[habitat destruction]] and introduction of [[invasive species]].<ref>{{cite web|url=http://www.scientificamerican.com/article/fact-or-fiction-the-sixth-mass-extinction-can-be-stopped/|title=Sixth Extinction extinctions|work=Scientific American|url-status=live|archive-url=https://web.archive.org/web/20140727234806/http://www.scientificamerican.com/article/fact-or-fiction-the-sixth-mass-extinction-can-be-stopped/|archive-date=27 July 2014}}</ref><ref>{{cite web|url=http://www.iucn.org/?4143/Extinction-crisis-continues-apace|title=Sixth Extinction|author=IUCN|work=IUCN|date=3 November 2009|url-status=live|archive-url=https://web.archive.org/web/20120729102308/http://iucn.org/?4143%2FExtinction-crisis-continues-apace|archive-date=29 July 2012}}</ref>