Editing Human evolution (section)

== Use of tools ==
[[File:Pierre taillée Melka Kunture Éthiopie fond.jpg|thumb|"A sharp rock", an [[Oldowan]] pebble tool, the most basic of human stone tools]]
[[File:Small bonfire.JPG|thumb|The harnessing of fire was a pivotal milestone in human history.]]
[[File:Acheuleanhandaxes.jpg|thumb|upright|[[Acheulean]] hand-axes from [[Kent]]. ''H.&nbsp;erectus'' [[flint]] work. The types shown are (clockwise from top) cordate, ficron and ovate.]]
[[File:Venus of Willendorf frontview retouched 2.jpg|thumb|upright|[[Venus of Willendorf]], an example of [[Paleolithic]] art, dated circa 30,000 years ago<ref name="PHYS">{{cite journal |last1=Weber |first1=G.W. |last2=Lukeneder |first2=A. |last3=Harzhauser |first3=M. |date=February 28, 2022 |title=The microstructure and origin of the Venus of Willendorf |journal=[[Scientific Reports]] |publisher=[[Nature (journal)|Nature]] |volume=12 |issue=2926 |page=2926 |doi=10.1038/s41598-022-06799-z |pmc=8885675 |pmid=35228605 |doi-access=free}}</ref>]]
{{See also|Hunting hypothesis}}

The use of tools has been interpreted as a sign of intelligence, and it has been theorized that tool use may have stimulated certain aspects of human evolution, especially the continued expansion of the human brain.<ref name="auto">{{cite journal |last=Ko |first=Kwang Hyun |title=Origins of human intelligence: The chain of tool-making and brain evolution |journal=Anthropological Notebooks |date=2016 |volume=22 |issue=1 |pages=5–22 |url= http://www.drustvo-antropologov.si/AN/PDF/2016_1/Anthropological_Notebooks_XXII_1_Ko.pdf |access-date=August 8, 2016 |archive-date=August 17, 2016 |archive-url= https://web.archive.org/web/20160817210720/http://www.drustvo-antropologov.si/AN/PDF/2016_1/Anthropological_Notebooks_XXII_1_Ko.pdf |url-status=live}}</ref> Paleontology has yet to explain the expansion of this organ over millions of years despite being extremely demanding in terms of energy consumption. The brain of a modern human consumes, on average, about 13 watts (260 kilocalories per day), a fifth of the body's resting power consumption.<ref>{{cite journal |last=Jabr |first=Ferris |date=July 18, 2012 |title=Does Thinking Really Hard Burn More Calories? |url= http://www.scientificamerican.com/article/thinking-hard-calories/ |journal=Scientific American |issn=0036-8733 |access-date=May 3, 2015 |archive-date=May 3, 2015 |archive-url= https://web.archive.org/web/20150503113428/http://www.scientificamerican.com/article/thinking-hard-calories/ |url-status=live}}</ref> Increased tool use would allow hunting for energy-rich meat products, and would enable processing more energy-rich plant products. Researchers have suggested that early hominins were thus under evolutionary pressure to increase their capacity to create and use tools.<ref>{{cite journal |last=Gibbons |first=Ann |date=May 29, 1998 |title=Solving the Brain's Energy Crisis |journal=[[Science (journal)|Science]] |volume=280 |issue=5368 |pages=1345–1347 |doi=10.1126/science.280.5368.1345 |issn=0036-8075 |pmid=9634409 |s2cid=28464775}}</ref>

Precisely when early humans started to use tools is difficult to determine, because the more primitive these tools are (for example, sharp-edged stones) the more difficult it is to decide whether they are natural objects or human artifacts.<ref name="auto" /> There is some evidence that the australopithecines (4 Ma) [[Osteodontokeratic culture|may have used broken bones as tools]], but this is debated.{{sfn|Robinson|2008|p=[https://books.google.com/books?id=-kOvkb-xbU8C&pg=PA398 398]}}

[[Tool use by animals|Many species make and use tools]], but it is the human genus that dominates the areas of making and using more complex tools. The oldest known tools are flakes from West Turkana, Kenya, which date to 3.3&nbsp;million years ago.<ref name="Harmand 310–315">{{Cite journal |last1=Harmand |first1=Sonia |last2=Lewis |first2=Jason E. |last3=Feibel |first3=Craig S. |last4=Lepre |first4=Christopher J. |last5=Prat |first5=Sandrine |last6=Lenoble |first6=Arnaud |last7=Boës |first7=Xavier |last8=Quinn |first8=Rhonda L. |last9=Brenet |first9=Michel |date=May 20, 2015 |title=3.3-million-year-old stone tools from Lomekwi 3, West Turkana, Kenya |journal=[[Nature (journal)|Nature]] |volume=521 |issue=7552 |pages=310–315 |doi=10.1038/nature14464 |pmid=25993961 |issn=0028-0836 |bibcode=2015Natur.521..310H |s2cid=1207285}}</ref> The next oldest stone tools are from [[Gona, Ethiopia]], and are considered the beginning of the Oldowan technology. These tools date to about 2.6&nbsp;million years ago.<ref>{{Cite journal |last1=Semaw |first1=Sileshi |last2=Rogers |first2=Michael J. |last3=Quade |first3=Jay |last4=Renne |first4=Paul R. |last5=Butler |first5=Robert F. |last6=Dominguez-Rodrigo |first6=Manuel |last7=Stout |first7=Dietrich |last8=Hart |first8=William S. |last9=Pickering |first9=Travis |last10=Simpson |first10=Scott W. |date=August 1, 2003 |title=2.6-Million-year-old stone tools and associated bones from OGS-6 and OGS-7, Gona, Afar, Ethiopia |journal=Journal of Human Evolution |volume=45 |issue=2 |pages=169–177 |doi=10.1016/S0047-2484(03)00093-9 |pmid=14529651 |issn=0047-2484 |bibcode=2003JHumE..45..169S}}</ref> A ''Homo'' fossil was found near some [[Oldowan]] tools, and its age was noted at 2.3&nbsp;million years old, suggesting that maybe the ''Homo'' species did indeed create and use these tools. It is a possibility but does not yet represent solid evidence.{{sfn|Freeman|Herron|2007|pp=786–788}} The [[third metacarpal styloid process]] enables the hand bone to lock into the wrist bones, allowing for greater amounts of pressure to be applied to the wrist and hand from a grasping thumb and fingers. It allows humans the dexterity and strength to make and use complex tools. This unique anatomical feature separates humans from other apes and other nonhuman primates, and is not seen in human fossils older than 1.8&nbsp;million years.<ref>{{cite journal |last1=Ward |first1=Carol V. |last2=Tocheri |first2=Matthew W. |last3=Plavcan |first3=J. Michael |last4=Brown |first4=Francis H. |last5=Manthi |first5=Fredrick Kyalo |date=January 7, 2014 |title=Early Pleistocene third metacarpal from Kenya and the evolution of modern human-like hand morphology |journal=[[Proceedings of the National Academy of Sciences of the United States of America]] |volume=111 |issue=1 |pages=121–124 |doi=10.1073/pnas.1316014110 |issn=0027-8424 |pmc=3890866 |pmid=24344276 |display-authors=3 |bibcode=2014PNAS..111..121W |doi-access=free}}</ref>

Bernard Wood noted that ''Paranthropus'' co-existed with the early ''Homo'' species in the area of the "Oldowan Industrial Complex" over roughly the same span of time. Although there is no direct evidence which identifies ''Paranthropus'' as the tool makers, their anatomy lends to indirect evidence of their capabilities in this area. Most paleoanthropologists agree that the early ''Homo'' species were indeed responsible for most of the Oldowan tools found. They argue that when most of the Oldowan tools were found in association with human fossils, ''Homo'' was always present, but ''Paranthropus'' was not.{{sfn|Freeman|Herron|2007|pp=786–788}}

In 1994, Randall Susman used the anatomy of opposable thumbs as the basis for his argument that both the ''Homo'' and ''Paranthropus'' species were toolmakers. He compared bones and muscles of human and chimpanzee thumbs, finding that humans have 3 muscles which are lacking in chimpanzees. Humans also have thicker metacarpals with broader heads, allowing more precise grasping than the chimpanzee hand can perform. Susman posited that modern anatomy of the human opposable thumb is an evolutionary response to the requirements associated with making and handling tools and that both species were indeed toolmakers.{{sfn|Freeman|Herron|2007|pp=786–788}}

{{anchor|Modern humans and the "Great Leap Forward" debate}}