| Revision as of 02:38, 17 November 2009 view sourceClueBot (talk | contribs)1,596,818 editsm Reverting possible vandalism by 98.127.75.84 to version by Mindmatrix. False positive? Report it. Thanks, ClueBot. (825089) (Bot)← Previous edit | Revision as of 02:48, 17 November 2009 view source BREAKTIME09 (talk | contribs)1 edit ←Replaced content with ''''Humans are the best things in the world! Te best humans are Gracie and Billie!!! ''''Tag: blankingNext edit → | ||
| Line 1: | Line 1: | ||
| '''Humans are the best things in the world! Te best humans are Gracie and Billie!!! | |||
| {{Redirect|Homo sapiens}} | |||
| ''' | |||
| {{two other uses|modern humans|other human species|Homo (genus)}} | |||
| {{Taxobox | |||
| | name = Human<ref name=msw3>{{MSW3 Groves | pages = | id = 12100795}}</ref> | |||
| | image = Akha cropped.png | |||
| | image_caption = Human male and female | |||
| | fossil_range = {{fossil range|0.2|0}} ] - Recent | |||
| | status = LC | |||
| | trend = increasing | |||
| | status_system = iucn3.1 | |||
| | regnum = ] | |||
| | phylum = ] | |||
| | classis = ]ia | |||
| | ordo = ]s | |||
| | familia = ]ae | |||
| | subfamilia = ] | |||
| | tribus = ] | |||
| | genus = '']'' | |||
| | species = '''''H. sapiens''''' | |||
| | subspecies = '''''H. s. sapiens''''' | |||
| | trinomial = ''Homo sapiens sapiens'' | |||
| | trinomial_authority = ], 1758 | |||
| }} | |||
| '''Humans''' are ] ]s belonging to the species '''''Homo sapiens''''' (]: "wise man" or "knowing man") in ], the great ] family.<ref>{{cite journal |author=Goodman M, Tagle D, Fitch D, Bailey W, Czelusniak J, Koop B, Benson P, Slightom J |title=Primate evolution at the DNA level and a classification of hominoids |journal=J Mol Evol |volume = 30 |issue=3 |pages=260 – 6 |year=1990 |id=PMID 2109087}}</ref><ref>{{cite web |title=Hominidae Classification |work=Animal Diversity Web @ UMich |url=http://animaldiversity.ummz.umich.edu/site/accounts/classification/Hominidae.html |accessdate=2006-09-25}}</ref> They are the only surviving member of the genus ''Homo''. Humans have a ] brain, capable of abstract ], ], ], and ]. This mental capability, combined with an erect body carriage that frees the arms for manipulating objects, has allowed humans to make far greater use of ]s than any other species. ] and fossil evidence indicates that ] originated in ] about 200,000 years ago.<ref></ref> Humans now inhabit every continent and ], with a ] of 6.8 billion as of November 2009.<ref name="popclock">{{cite web | |||
| |url=http://www.census.gov/ipc/www/popclockworld.html | |||
| |title=World POPClock Projection | |||
| |accessdate=2009-09-19 | |||
| |publisher=U.S. Census Bureau, Population Division/International Programs Center}}</ref> | |||
| Like most ], humans are social by nature. However, humans are uniquely adept at utilizing systems of communication for self-expression, the exchange of ideas, and organization. Humans create complex ]s composed of many cooperating and competing groups, from ] to ]s. ]s between humans have established an extremely wide variety of values, ], and rituals, which together form the basis of human society. Humans have a marked appreciation for beauty and aesthetics which, combined with the human desire for self-expression, has led to cultural innovations such as art, literature and music. | |||
| Humans are noted for their desire to understand and influence their environment, seeking to explain and manipulate natural phenomena through science, philosophy, mythology and religion. This natural curiosity has led to the development of advanced tools and skills, which are passed down ]; humans are the only extant species known to build fires, cook their food, clothe themselves, and use numerous other ]. | |||
| ==Name== | |||
| {{See|Man (word)|List of alternative names for the human species}} | |||
| The English adjective ''human'' is a ] loan from ] ''{{lang|fro|humain}}'', ultimately from ] ''{{lang|la|hūmānus}}'', the adjective of ''{{lang|la|homō}}'' "man". Use as a noun (with a plural ''humans'') dates to the 16th century.<ref>], ] "human".</ref> The native English term '']'' is now often reserved for male adults, but can still be used for "mankind" in general in Modern English.<ref>The ] | |||
| considers ''obsolete'' the sense "a designation applied equally to particular individuals of either sex", citing a 1597 source as the most recent (''The Lord had but one paire of men in Paradise.'') while it continues to endorse the sense "as a general or indefinite designation" as current in English.</ref> The word is from ] ''{{lang|gem|*]}}'', from a ](PIE) root ''{{PIE|*man-}}'', cognate to Sanskrit '']-''. | |||
| The ] '']'' is a learned 18th century derivation from Latin ''{{lang|la|homō}}'' "man", ultimately "earthly being" (] ''{{lang|la|hemō}}'', cognate to Old English ''{{lang|ang|guma}}'' "man", from ] ''{{PIE|*dʰǵʰ<sub>e</sub>mon-}}'', meaning 'earth' or 'ground').<ref>] s.v. "g'hðem" pp. 414-416; "Homo." Dictionary.com Unabridged (v 1.1). Random House, Inc. 23 Sep. 2008. <Dictionary.com http://dictionary.reference.com/browse/Homo>.</ref> | |||
| ==History== | |||
| ===Evolution=== | |||
| {{Main|Human evolution}} | |||
| {{See|Anthropology|Homo (genus)}} | |||
| ]'', a human ancestor that had developed ], but which lacked the large brain of modern humans]] | |||
| The scientific study of ] encompasses the development of the genus '']'', but usually involves studying other ] and ] as well, such as '']''. "Modern humans" are defined as the ''Homo sapiens'' ], of which the only extant ] is known as '']''. '']'' (roughly translated as "elder wise human"), the other known subspecies, is now extinct.<ref>, by Philip L. Walker and Edward H. Hagen, Dept. of Anthropology, University of California, Santa Barbara, retrieved April 5, 2005.</ref> '']'', which became extinct 30,000 years ago, has sometimes been classified as a subspecies, "''Homo sapiens neanderthalensis''", but genetic studies now suggest a divergence of the Neanderthal species from ''Homo sapiens'' about 500,000 years ago.<ref>Green, R. E., Krause, J, Ptak, S. E., Briggs, A. W., Ronan, M. T., Simons, J. F., et al. (2006) Analysis of one million base pairs of Neanderthal DNA. Nature, 16, 330–336. http://www.nature.com/nature/journal/v444/n7117/abs/nature05336.html</ref> Similarly, the few specimens of '']'' have also occasionally been classified as a subspecies, but this is not widely accepted. Anatomically modern humans first appear in the fossil record in Africa about 195,000 years ago, and studies of molecular biology give evidence that the approximate time of divergence from the common ancestor of all modern human populations was 200,000 years ago.<ref>http://www.nsf.gov/news/news_summ.jsp?cntn_id=102968</ref><ref> | |||
| http://news.bbc.co.uk/2/hi/science/nature/4269299.stm</ref><ref> - URL retrieved May 15, 2009</ref><ref>{{cite journal |author=Alemseged, Z., Coppens, Y., Geraads, D. |title=Hominid cranium from Homo: Description and taxonomy of Homo-323-1976-896 |journal=Am J Phys Anthropol |volume=117 |issue=2 |pages=103–12 |year=2002 |pmid=11815945 |doi=10.1002/ajpa.10032}}</ref><ref>{{cite journal |author=Stoneking, Mark; Soodyall, Himla |title=Human evolution and the mitochondrial genome |journal=Current Opinion in Genetics & Development |volume=6 |issue=6 |pages=731–6 |year=1996 |doi=10.1016/S0959-437X(96)80028-1}}</ref> The broad study of African genetic diversity headed by Dr. Sarah Tishkoff found the ] to express the greatest genetic diversity among the 113 distinct populations sampled, making them one of 14 "ancestral population clusters". The research also located the origin of modern human migration in south-western Africa, near the coastal border of ] and ].<ref name="news.bbc.co.uk">, 1 May 2009; the results were published in the online edition of the journal ''Science''.</ref> | |||
| The closest living relatives of humans are ]s and ]s, but humans did not evolve from these apes: instead these apes share a ] with modern humans.<ref name=Wood>{{cite journal |author=Wood B, Richmond BG |title=Human evolution: taxonomy and paleobiology |journal=J. Anat. |volume=197 ( Pt 1) |issue= |pages=19–60 |year=2000 |month=July |pmid=10999270 |pmc=1468107 |doi=10.1046/j.1469-7580.2000.19710019.x}}</ref> Humans are probably most closely related to two ] species: ] and ].<ref name=Wood/> Full ] sequencing has resulted in the conclusion that "after 6.5 years of separate evolution, the differences between chimpanzee and human are ten times greater than those between two unrelated people and ten times less than those between rats and mice". Suggested concurrence between human and chimpanzee DNA sequences range between 95% and 99%.<ref>], ''Bonobo''. Berkeley: University of California Press, 1997. ISBN 0-520-20535-9 </ref><ref>{{cite journal | author=Britten RJ | title=Divergence between samples of chimpanzee and human DNA sequences is 5%, counting indels | url=http://www.pnas.org/cgi/content/full/99/21/13633 | journal=Proc Natl Acad Sci USA | year=2002 | pages=13633–5 | volume=99 | issue=21 | pmid=12368483 | doi=10.1073/pnas.172510699}}</ref><ref>{{cite journal | author = Wildman, D., Uddin, M., Liu, G., Grossman, L., Goodman, M. | title = Implications of natural selection in shaping 99.4% nonsynonymous DNA identity between humans and chimpanzees: enlarging genus Homo | url=http://www.pnas.org/cgi/content/full/100/12/7181 | journal = Proc Natl Acad Sci USA | volume = 100 | issue = 12 | pages = 7181–8 | year = 2003 | pmid = 12766228 | doi = 10.1073/pnas.1232172100}}</ref><ref>{{cite journal | author = Ruvolo M | title = Molecular phylogeny of the hominoids: inferences from multiple independent DNA sequence data sets | url=http://mbe.oxfordjournals.org/cgi/reprint/14/3/248 | journal = Mol Biol Evol | volume = 14 | issue = 3 | pages = 248–65 | year = 1997 | pmid = 9066793 | month = Mar | day = 01}}</ref> It has been estimated that the human ] diverged from that of chimpanzees about five million years ago, and from that of ]s about eight million years ago. However, a hominid skull discovered in ] in 2001, classified as '']'', is approximately seven million years old, which may indicate an earlier divergence.<ref>{{cite journal | author = Brunet, M., Guy, F., Pilbeam, D., Mackaye, H., Likius, A., Ahounta, D., Beauvilain, A., Blondel, C., Bocherens, H., Boisserie, J., De Bonis, L., Coppens, Y., Dejax, J., Denys, C., Duringer, P., Eisenmann, V., Fanone, G., Fronty, P., Geraads, D., Lehmann, T., Lihoreau, F., Louchart, A., Mahamat, A., Merceron, G., Mouchelin, G., Otero, O., Pelaez Campomanes, P., Ponce De Leon, M., Rage, J., Sapanet, M., Schuster, M., Sudre, J., Tassy, P., Valentin, X., Vignaud, P., Viriot, L., Zazzo, A., Zollikofer, C. | title = A new hominid from the Upper Miocene of Chad, Central Africa | url=http://www.nature.com/nature/journal/v418/n6894/full/nature00879.html | journal = Nature | volume = 418 | issue = 6894 | pages = 145–51 | year = 2002 | pmid = 12110880 | doi = 10.1038/nature00879}}</ref> | |||
| Human evolution is characterized by a number of important morphological, developmental, physiological and behavioural changes, which have taken place since the split between the last common ancestor of humans and chimpanzees. The first major morphological change was the evolution of a bipedal locomotor adaptation from an arboreal or semi-arboreal one,<ref>Vančata1 V., & Vančatová, M. A. "". Springer Netherlands, Volume 2, Number 6, December 1987. pp.517–537.</ref> with all its attendant adaptations, such as a ] knee, low intermembral index (long legs relative to the arms), and reduced upper-body strength. | |||
| Later, ancestral humans developed a much larger brain – typically 1,400 cm³ in modern humans, over twice the size of that of a chimpanzee or gorilla. The pattern of human postnatal brain growth differs from that of other apes (]), and allows for extended periods of social learning and ] in juvenile humans. ] argue that the differences between the structure of ]s and those of other apes are even more significant than their differences in size. | |||
| Other significant morphological changes included: the evolution of a power and precision grip;<ref>Brues, Alice M. & Snow, Clyde C. "Physical Anthropology". ''Biennial Review of Anthropology'', Vol. 4, 1965. pp. 1–39.</ref> a reduced masticatory system; a reduction of the ]; and the descent of the ] and ], making speech possible. An important physiological change in humans was the evolution of hidden oestrus, or ], which may have coincided with the evolution of important behavioural changes, such as pair bonding. Another significant behavioural change was the development of ], with human-made objects becoming increasingly common and diversified over time. The relationship between all these changes is the subject of ongoing debate.<ref>Boyd, Robert & Silk, Joan B. (2003). ''How Humans Evolved''. New York: Norton & Company. ISBN 0-393-97854-0.</ref><ref>Dobzhansky, Theodosius (1963). ''Anthropology and the natural sciences-The problem of human evolution'', ''Current Anthropology '4'' (2): 138–148.</ref> | |||
| The forces of ] have continued to operate on human populations, with evidence that certain regions of the genome display ] in the past 15,000 years.<ref>{{cite news | url = http://www.nytimes.com/2006/03/07/science/07evolve.html|access_date=2008-07-02 | title = Still Evolving, Human Genes Tell New Story | last =Wade | first = N | date = 2006-03-07 | accessdate = 2008-07-10 | publisher = ] }}</ref> | |||
| ===Paleolithic=== | |||
| {{See|Recent African Origin|Archaic Homo sapiens|Upper Paleolithic|Early human migrations}} | |||
| ] appeared in the Upper Paleolithic: The ] figurine, one of the earliest known depictions of the human body, dates to approximately 29,000–25,000 ] (]).]] | |||
| ] evolved from ] in Africa in the ], about 200,000 years ago. By the beginning of the ] 50,000 BP, full ], including ], ] and other ]s had developed. | |||
| The broad study of African genetic diversity headed by Dr. Sarah Tishkoff found the ] to express the greatest genetic diversity among the 113 distinct populations sampled, making them one of 14 "ancestral population clusters". The research also located the origin of modern human migration in south-western Africa, near the coastal border of ] and ].<ref name="news.bbc.co.uk"/> | |||
| The ] migration is estimated to have occurred about 70,000 years BP. Modern humans subsequently spread to all continents, replacing earlier hominids: they inhabited ] and ] by 40,000 BP, and the Americas at least 14,500 years BP.<ref>Wolman, David (2008). ''National Geographic''</ref> They displaced '']'' and other species descended from '']'' (which had inhabited Eurasia as early as 2 million years ago) through more successful ] and competition for ].<ref>. ''The Observer.'' May 17, 2009.</ref> | |||
| Evidence from ] accumulating since the 1990s has lent strong support to the "out-of-Africa" scenario, and has marginalized the competing ], which proposed that modern humans evolved, at least in part, from independent hominid populations.<ref>{{cite journal |author=Eswaran V, Harpending H, Rogers AR |title=Genomics refutes an exclusively African origin of humans |journal=J. Hum. Evol. |volume=49 |issue=1 |pages=1–18 |year=2005 |month=July |pmid=15878780 |doi=10.1016/j.jhevol.2005.02.006 |url=}}</ref> | |||
| Geneticists Lynn Jorde and ] of the ] propose that the variation in human DNA is minute compared to that of other species. They also propose that during the ], the human population was reduced to a ] – no more than 10,000, and possibly as few as 1,000 – resulting in a very small residual gene pool. Various reasons for this hypothetical bottleneck have been postulated, one being the ].<ref>, ], 3 February 2000</ref> | |||
| ===Transition to civilization=== | |||
| {{Main|Neolithic revolution|Cradle of Civilization}} | |||
| {{See|History of the world}} | |||
| ], and ] of animals, led to stable ].]] | |||
| Until c. 10,000 years ago, most humans lived as ]s. They generally lived in small nomadic groups known as ]. The advent of agriculture prompted the ], when access to food surplus led to the formation of permanent human settlements, the ] of animals and the ]. Agriculture encouraged trade and cooperation, and led to complex society. Because of the significance of this date for human society, it is the epoch of the ] or Human Era. | |||
| About 6,000 years ago, the first proto-states developed in ], ]'s ] and the ]. Military forces were formed for protection, and government bureaucracies for administration. States cooperated and competed for resources, in some cases waging wars. Around 2,000–3,000 years ago, some states, such as ], ], China, ], and ], developed through conquest into the first expansive empires. Influential religions, such as ], originating in the ], and ], a religious tradition that originated in South Asia, also rose to prominence at this time. | |||
| The late ] saw the rise of revolutionary ideas and technologies. In China, an advanced and urbanized society promoted innovations and sciences, such as printing and seed drilling. In India, major advancements were made in mathematics, philosophy, religion and metallurgy. The ] saw major scientific advancements in ] empires. In Europe, the rediscovery of ] learning and inventions such as the printing press led to the ] in the 15th and 16th centuries. Over the next 500 years, ] and ] brought much of the Americas, Asia, and Africa under European control, leading to later struggles for independence. The ] in the 17th century and the ] in the 18th–19th centuries promoted major innovations in transport, such as the railway and automobile; ], such as coal and electricity; and government, such as ] and ]. | |||
| With the advent of the ] at the end of the 20th century, modern humans live in a world that has become increasingly ] and interconnected. As of 2008, over 1.4 billion humans are connected to each other via the ],<ref>{{cite web|url=http://www.internetworldstats.com/stats.htm|title=www.internetworldstats.com/stats.htm<!-- INSERT TITLE -->|accessdate=2008-08-08}}</ref> and 3.3 billion by ] subscriptions.<ref>{{cite web|url=http://investing.reuters.co.uk/news/articleinvesting.aspx?type=media&storyID=nL29172095|title=www.investing.reuters.co.uk/news/articleinvesting.aspx?type=media&storyID=nL29172095<!-- INSERT TITLE -->|accessdate=2008-08-08}}</ref> | |||
| Although interconnection between humans has encouraged the growth of ], ], ], and ], it has also led to culture clashes and the development and use of ]. Human civilization has led to environmental destruction and pollution, producing an ongoing ] of other forms of life called the ],<ref>{{cite journal |author=Pimm S, Raven P, Peterson A, Sekercioglu CH, Ehrlich PR |title=Human impacts on the rates of recent, present, and future bird extinctions |doi= 10.1073/pnas.0604181103 |journal=Proc. Natl. Acad. Sci. U.S.A. |volume=103 |issue=29 |pages=10941–6 |year=2006 |pmid=16829570}}<br />*{{cite journal |author=Barnosky AD, Koch PL, Feranec RS, Wing SL, Shabel AB |title=Assessing the causes of late Pleistocene extinctions on the continents |journal=Science |volume=306 |issue=5693 |pages=70–5 |year=2004 |pmid=15459379 |doi=10.1126/science.1101476 }}</ref> that may be further accelerated by ] in the future.<ref>{{cite journal |author=Lewis OT |title=Climate change, species-area curves and the extinction crisis |url=http://www.journals.royalsoc.ac.uk/content/711761513317h856/fulltext.pdf |format=PDF|journal=Philos. Trans. R. Soc. Lond., B, Biol. Sci. |volume=361 |issue=1465 |pages=163–71 |year=2006 |pmid=16553315 |doi=10.1098/rstb.2005.1712}}</ref> | |||
| ==Habitat and population== | |||
| {{See|Demography|World population}} | |||
| ] | |||
| Early ] were dependent on proximity to ] and, depending on the ], other ], such as ] for growing crops and grazing ], or seasonally by ] populations of prey. However, humans have a great capacity for altering their ] by various methods, such as through ], ], ], ], ] goods, ] and ]. With the advent of large-scale trade and transport infrastructure, proximity to these resources has become unnecessary, and in many places, these factors are no longer a driving force behind the growth and decline of a population. Nonetheless, the manner in which a habitat is altered is often a major determinant in population change. | |||
| Technology has allowed humans to colonize all of the continents and adapt to virtually all climates. Within the last few decades, humans have explored Antarctica, the ocean depths, and outer space, although large-scale colonization of these environments is not yet feasible. With a population of over six billion, humans are among the most numerous of the large mammals. Most humans (61%) live in Asia. The remainder live in the Americas (14%), Africa (14%), Europe (11%), and Oceania (0.5%). | |||
| Human habitation within ]s in hostile environments, such as Antarctica and outer space, is expensive, typically limited in duration, and restricted to scientific, military, or industrial expeditions. Life in space has been very sporadic, with no more than thirteen humans in space at any given time. Between 1969 and 1972, two humans at a time spent brief intervals on the ]. As of {{Monthyear}}, no other celestial body has been visited by humans, although there has been a continuous human presence in space since the launch of the initial crew to inhabit the ] on October 31, 2000. However, other celestial bodies have been visited by human-made objects. | |||
| Since 1800, the ] has increased from one billion to over six billion.<ref>Whitehouse, David. "". BBC News, August 05, 1999. Retrieved on February 05, 2008.</ref> In 2004, some 2.5 billion out of 6.3 billion people (39.7%) lived in ]s, and this percentage is expected to continue to rise throughout the 21st century. In February 2008, the U.N. estimated that half the world's population will live in ]s by the end of the year.<ref>, BBC News</ref> Problems for humans living in ] include various forms of ] and ],<ref> U.S. Department of Justice, Bureau of Justice Statistics,. Accessed 29 Oct 2006</ref> especially in inner city and suburban slums. Benefits of urban living include increased literacy, access to the global canon of human knowledge and decreased susceptibility to rural ].{{Citation needed|date=October 2009}} | |||
| Humans have had a dramatic effect on the ]. As humans are rarely preyed upon, they have been described as ].<ref>'']'' (1998). .</ref> Currently, through land development, combustion of ] and ], humans are thought to be the main contributor to global ].<ref>{{cite web|url=http://www.grida.no/climate/ipcc_tar/wg1/007.htm|title=www.grida.no/climate/ipcc_tar/wg1/007.htm<!-- INSERT TITLE -->|accessdate=2007-05-30}}</ref> Human activity is believed to be a major contributor to the ongoing ], which is a form of ]. If this continues at its current rate it is predicted that it will wipe out half of all species over the next century.<ref>]. . ''AAAS Atlas of Population & Environment''.</ref><ref>] (2002). ''in The Future of Life''.</ref> | |||
| ==Biology== | |||
| {{Main|Human biology}} | |||
| ===Anatomy=== | |||
| {{Main|Human anatomy}} | |||
| {{See|Human physical appearance|Anatomically modern humans}} | |||
| ] | |||
| Human body types vary substantially. Although body size is largely determined by ]s, it is also significantly influenced by environmental factors such as ] and ]. The average ] of an adult human is about 1.5 to 1.8 m (5 to 6 feet) tall, although this varies significantly from place to place.<ref>{{cite journal | author = de Beer H | title = Observations on the history of Dutch physical stature from the late-Middle Ages to the present | journal = Econ Hum Biol | volume = 2 | issue = 1 | pages = 45–55 | year = 2004 | pmid = 15463992 | doi = 10.1016/j.ehb.2003.11.001}}</ref><ref>"Pygmy." Britannica Concise Encyclopedia. Encyclopædia Britannica, Inc., 2006. Answers.com Accessed 30 Oct. 2006. http://www.answers.com/topic/pygmy</ref> The average ] of an adult male is 76–83 kg (168–183 lbs) and 54–64 kg (120–140 lbs) for adult females.<ref></ref> Weight can also vary greatly (e.g. ]). Unlike most other primates, humans are capable of fully bipedal ], thus leaving their arms available for manipulating objects using their ]s, aided especially by opposable thumbs. | |||
| Although humans appear hairless compared to other primates, with notable ] growth occurring chiefly on the top of the head, underarms and pubic area, the average human has more ] on his or her body than the average chimpanzee. The main distinction is that human hairs are shorter, finer, and less heavily pigmented than the average chimpanzee's, thus making them harder to see.<ref>''Why Humans and Their Fur Parted Way'' by Nicholas Wade, ''New York Times'', August 19, 2003.</ref> | |||
| The hue of human skin and hair is determined by the presence of ]s called ]s. Human skin hues can range from very dark brown to very pale pink. Human hair ranges from ] to ] to ] to most commonly ].<ref>{{cite journal | author=Rogers, Alan R., Iltis, David & Wooding, Stephen | year=2004 | title=Genetic variation at the MC1R locus and the time since loss of human body hair | journal=Current Anthropology | volume=45 | issue=1 | pages=105–108 | doi=10.1086/381006}}</ref> This depends on the amount of melanin (an effective sun blocking pigment) in the skin and hair, with hair melanin concentrations in hair fading with increased age, leading to ] or even white hair. Most researchers believe that skin darkening was an adaptation that evolved as a protection against ] ]. However, more recently it has been argued that particular skin colors are an adaptation to balance ], which is destroyed by ultraviolet radiation, and vitamin D, which requires sunlight to form.<ref>Jablonski, N.G. & Chaplin, G. (2000). '''' (pdf), 'Journal of Human Evolution 39: 57–106.</ref> The skin pigmentation of contemporary humans is geographically stratified, and in general correlates with the level of ultraviolet radiation. Human skin also has a capacity to darken (]) in response to exposure to ultraviolet radiation.<ref>{{cite journal |author=Harding RM, Healy E, Ray AJ, ''et al.'' |title=Evidence for variable selective pressures at MC1R |journal=Am. J. Hum. Genet. |volume=66 |issue=4 |pages=1351–61 |year=2000 |month=April |pmid=10733465 |pmc=1288200 |doi=10.1086/302863 |url=}}</ref><ref>Robin, Ashley (1991). ''Biological Perspectives on Human Pigmentation''. Cambridge: Cambridge University Press.</ref> Humans tend to be physically weaker than other similarly sized primates, with young, conditioned male humans having been shown to be unable to match the strength of female ]s which are at least three times stronger.<ref name="Schwartz">{{cite book | author = Schwartz, Jeffrey |url = | title = The Red Ape: Orangutans and Human Origins | year = 1987 | pages = 286 | isbn = 0813340640 | publisher = Westview Press | location = Cambridge, MA}}</ref> | |||
| {|class="wikitable" align="right" | |||
| |colspan=3| <div align=center>'''Constituents of the human body''' <br> <font size=1>In a person weighing 60 kg</div> | |||
| |- | |||
| ! Constituent !! Weight<ref name=Burton/> !! Percentage of atoms<ref name=Burton> in Chemical storylines. Author: George Burton. Edition 2, illustrated. Publisher: Heinemann, 2000. ISBN 0435631195, 9780435631192. Length: 312 pages</ref> | |||
| |- | |||
| | ] || 38.8 kg || 25.5% | |||
| |- | |||
| | ] || 10.9 kg || 9.5% | |||
| |- | |||
| | ]|| 6.0 kg || 63.0% | |||
| |- | |||
| | ] || 1.9 kg || 1.4% | |||
| |- | |||
| | Other || 2.4 kg || 0.6% | |||
| |} | |||
| Humans have proportionately shorter palates and much smaller teeth than other primates. They are the only primates to have short, relatively flush ]. Humans have characteristically crowded teeth, with gaps from lost teeth usually closing up quickly in young specimens. Humans are gradually losing their ], with some individuals having them congenitally absent.<ref name="Revolution">{{cite book | author = Collins, Desmond |url = | title = The Human Revolution: From Ape to Artist | year = 1976 | pages = 208 | id = }}</ref> | |||
| ===Physiology=== | |||
| {{Main|Human physiology}} | |||
| Human physiology is the science of the mechanical, physical, and biochemical functions of humans in good health, their organs, and the cells of which they are composed. The principal level of focus of physiology is at the level of organs and systems. Most aspects of human physiology are closely homologous to corresponding aspects of animal physiology, and animal experimentation has provided much of the foundation of physiological knowledge. Anatomy and physiology are closely related fields of study: anatomy, the study of form, and physiology, the study of function, are intrinsically tied and are studied in tandem as part of a medical curriculum. | |||
| ===Genetics=== | |||
| {{Main|Human genetics}} | |||
| Humans are a ] species. Each ] ] has two sets of 23 ]s, each set received from one parent. There are 22 pairs of ]s and one pair of ]. By present estimates, humans have approximately 20,000–25,000 genes. Like other mammals, humans have an ], so that ]s have the sex chromosomes XX and ]s have XY. The X chromosome carries many genes not on the Y chromosome, which means that ] diseases associated with X-linked genes, such as ], affect men more often than women. | |||
| ===Life cycle=== | |||
| ] | |||
| The human ] is similar to that of other ]l mammals. The ] divides inside the female's ] to become an embryo, which over a period of thirty-eight weeks (9 months) of ] becomes a human fetus. After this span of time, the fully grown fetus is birthed from the woman's body and breathes independently as an infant for the first time. At this point, most modern cultures recognize the baby as a person entitled to the full protection of the law, though some jurisdictions extend various levels of personhood earlier to human fetuses while they remain in the uterus. | |||
| Compared with other species, human ] is dangerous. Painful labors lasting twenty-four hours or more are not uncommon and sometimes leads to the death of the mother, or the child.<ref>According to the July 2, 2007 '']'' magazine, a woman dies in childbirth every minute, most often due to uncontrolled bleeding and infection, with the world's poorest women most vulnerable. The lifetime risk is 1 in 16 in ], compared to 1 in 2,800 in developed countries.</ref> This is because of both the relatively large fetal head circumference (for housing the brain) and the mother's relatively narrow ] (a trait required for successful bipedalism, by way of natural selection).<ref>{{cite journal | author = LaVelle M | title = Natural selection and developmental sexual variation in the human pelvis | journal = Am J Phys Anthropol | volume = 98 | issue = 1 | pages = 59–72 | year = 1995 | pmid = 8579191 | doi = 10.1002/ajpa.1330980106}}</ref><ref>{{cite journal | author = Correia H, Balseiro S, De Areia M | title = Sexual dimorphism in the human pelvis: testing a new hypothesis | journal = Homo | volume = 56 | issue = 2 | pages = 153–60 | year = 2005 | pmid = 16130838 | doi = 10.1016/j.jchb.2005.05.003}}</ref> The chances of a successful labor increased significantly during the 20th century in wealthier countries with the advent of new medical technologies. In contrast, pregnancy and ] remain hazardous ordeals in developing regions of the world, with maternal death rates approximately 100 times more common than in developed countries.<ref>{{cite journal | author = Rush D | title = Nutrition and maternal mortality in the developing world | journal = Am J Clin Nutr | volume = 72 | issue = 1 Suppl | pages = 212 S–240 S | year = 2000 | pmid = 10871588}}</ref> | |||
| In developed countries, infants are typically 3–4 kg (6–9 pounds) in weight and 50–60 cm (20–24 inches) in height at birth.<ref>{{cite web|url=http://childinfo.org/areas/birthweight/|title=Low Birthweight|accessdate=2007-05-30}}</ref> However, low ] is common in developing countries, and contributes to the high levels of ] in these regions.<ref>{{cite journal | author = Khor G | title = Update on the prevalence of malnutrition among children in Asia | journal = Nepal Med Coll J | volume = 5 | issue = 2 | pages = 113–22 | year = 2003 | pmid = 15024783}}</ref> Helpless at birth, humans continue to grow for some years, typically reaching ] at 12 to 15 years of age. Females continue to develop physically until around the age of 18, whereas male development continues until around age 21. The human life span can be split into a number of stages: infancy, ], ], ], ]hood and ]. The lengths of these stages, however, have varied across cultures and time periods. Compared to other primates, humans experience an unusually rapid growth spurt during adolescence, where the body grows 25% in size. Chimpanzees, for example, grow only 14%, with no pronounced spurt.<ref>Leakey, Richard; Lewin, Roger. Origins Reconsidered - In Search of What Makes Us Human. Sherma B.V., 1992.</ref> The presence of the growth spurt is probably necessary to keep children physically small until they are psychologically mature. Humans are one of the few species in which females undergo ]. It has been proposed that menopause increases a woman's overall reproductive success by allowing her to invest more time and resources in her existing offspring and/or their children (the ]), rather than by continuing to bear children into old age.<ref>{{cite book | last = Diamond | first = Jared | authorlink = Jared_M._Diamond | title = Why is Sex Fun? The Evolution of Human Sexuality | publisher = Basic Books | date = 1997 | pages = 167–170 | isbn = ISBN 0-465-03127-7}}</ref><ref>{{cite journal |author=Peccei, J.S.|title=Menopause: Adaptation or Epiphenomenon? |journal=Evolutionary Anthropology |volume=10 |issue= |pages=47–57 |year=2001 |pmid=|doi= |url= http://www.biology.ed.ac.uk/public/conferences/evolbiol2006/papers/Peccei.pdf}}</ref> | |||
| There are significant differences in life expectancy around the world. The developed world is generally aging, with the median age around 40 years (highest in Monaco at 45.1 years). In the ] the median age is between 15 and 20 years. Life expectancy at birth in ] is 84.8 years for a female and 78.9 for a male, while in ], primarily because of ], it is 31.3 years for both sexes.<ref> ], pp. 363–366, November 9, 2006</ref> While one in five Europeans is 60 years of age or older, only one in twenty Africans is 60 years of age or older.<ref>, U.S. Central Intelligence Agency, retrieved April 2, 2005.</ref> The number of ]s (humans of age 100 years or older) in the world was estimated by the ] at 210,000 in 2002.<ref>, United Nations press release, February 28, 2002, retrieved April 2, 2005</ref> At least one person, ], is known to have reached the age of 122 years; higher ages have been claimed but they are not well substantiated. Worldwide, there are 81 men aged 60 or older for every 100 women of that age group, and among the oldest, there are 53 men for every 100 women. | |||
| <gallery> | |||
| File:Burkina Faso girl.jpg|Girl (before puberty) | |||
| File:Punjabi woman smile.jpg|Woman of reproductive age | |||
| Image:HappyPensioneer.jpg|Older woman (after menopause) | |||
| </gallery> | |||
| <gallery> | |||
| File:Kirgisischer Junge.JPG|Boy (before puberty) | |||
| File:Kabul man.jpg|Middle aged man | |||
| File:Old man from Tajikistan.jpg|Elderly man | |||
| </gallery> | |||
| ===Diet=== | |||
| {{See|Diet (nutrition)}} | |||
| Until the development of agriculture approximately 10,000 years ago, ''Homo sapiens'' employed a hunter-gatherer method as their sole means of food collection. This involved combining stationary food sources (such as fruits, grains, tubers, and mushrooms, insect larvae and aquatic molluscs) with ], which must be hunted and killed in order to be consumed.<ref>{{cite journal |author=Cordain L, Eaton SB, Sebastian A, ''et al.'' |title=Origins and evolution of the Western diet: health implications for the 21st century |journal=Am. J. Clin. Nutr. |volume=81 |issue=2 |pages=341–54 |year=2005 |month=February |pmid=15699220}}</ref> It has been proposed that humans have used fire to prepare and ] food since the time of their divergence from '']''.<ref>{{cite journal |author=Ulijaszek SJ |title=Human eating behaviour in an evolutionary ecological context |journal=Proc Nutr Soc |volume=61 |issue=4 |pages=517–26 |year=2002 |month=November |pmid=12691181}}</ref> | |||
| Humans are ], capable of consuming both plant and animal products.<ref>{{cite journal |author=Haenel H |title=Phylogenesis and nutrition |journal=Nahrung |volume=33 |issue=9 |pages=867–87 |year=1989 |pmid=2697806}}</ref> Varying with available food sources in regions of habitation, and also varying with cultural and religious norms, human groups have adopted a range of diets, from purely ] to primarily ]. In some cases, dietary restrictions in humans can lead to ]; however, stable human groups have adapted to many dietary patterns through both genetic specialization and cultural conventions to utilize nutritionally balanced food sources.<ref>{{cite journal| journal=Journal of the American Dietetic Association| year=2003| volume=103| issue=6| pages=748–765| title=Vegetarian Diets| doi=10.1053/jada.2003.50142}}</ref> The human diet is prominently reflected in human culture, and has led to the development of ]. | |||
| In general, humans can survive for two to eight weeks without food, depending on stored body fat. Survival without water is usually limited to three or four days. Lack of food remains a serious problem, with about 36 million humans starving to death every year.<ref>] Information Service. . ], March 29, 2004, p. 6. “Around 36 million people died from hunger directly or indirectly every year.”.</ref> Childhood malnutrition is also common and contributes to the global burden of disease.<ref>{{cite journal | author = Murray C, Lopez A | title = Global mortality, disability, and the contribution of risk factors: Global Burden of Disease Study | journal = Lancet | volume = 349 | issue = 9063 | pages = 1436–42 | year = 1997 | pmid = 9164317 | doi = 10.1016/S0140-6736(96)07495-8}}</ref> However global food distribution is not even, and ] among some human populations has increased to almost ] proportions, leading to health complications and increased mortality in some ], and a few ]. The United States ] (CDC) state that 32% of American adults over the age of 20 are obese, while 66.5% are obese or overweight. Obesity is caused by consuming more ]s than are expended, with many attributing excessive weight gain to a combination of overeating and insufficient ]. | |||
| Around ten thousand years ago, ],<ref> | |||
| - URLs retrieved February 19, 2007</ref> which substantially altered their diet. This has led to increased populations, the development of cities, and because of increased population density, the wider spread of ]s. The types of food consumed, and the way in which they are prepared, has varied widely by time, location, and culture. | |||
| ===Sleep=== | |||
| {{Main|Sleep}} | |||
| Humans are generally ]. The average ] requirement is between seven and nine continuous hours a day for an adult and nine to ten hours for a child; elderly people usually sleep for six to seven hours. Experiencing less sleep than this is common in modern societies; this ] can have negative effects. A sustained restriction of adult sleep to four hours per day has been shown to correlate with changes in physiology and mental state, including fatigue, aggression, and bodily discomfort. | |||
| ==Psychology== | |||
| ]'s ]. Sketch by Priyan Weerappuli]] | |||
| {{Main|Psychology}} | |||
| {{See|Human brain|Mind}} | |||
| The ], the focal point of the ] in humans, controls the ]. In addition to controlling "lower", involuntary, or primarily ] activities such as ] and ], it is also the locus of "higher" order functioning such as ], ]ing, and ].<ref>, ''The Secret Life of the Brain'', Public Broadcasting Service, retrieved April 3, 2005.</ref> These ] constitute the ], and, along with their ]al consequences, are studied in the field of ]. | |||
| Generally regarded as more capable of these higher order activities, the human brain is believed to be more "intelligent" in general than that of any other known species. While some have larger brains or higher brain to body mass ratios,{{Citation needed|date=September 2009}} and some are capable of creating structures and using simple tools—mostly through instinct and mimicry—human technology is vastly more complex, and is constantly evolving and improving through time. | |||
| Although being vastly more advanced than many species in cognitive abilities, most of these abilities are known in primitive form among other species. Modern anthropology has tended to bear out ] proposition that "the difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind".<ref name="AnthropologyTodayApr07">Jonathan Benthall '''' ] 23/2 (April 2007):1</ref> | |||
| ===Consciousness and thought=== | |||
| {{Main|Consciousness|Cognition}} | |||
| Humans are one of only nine species to pass the ]—which tests whether an animal recognizes its reflection as an image of itself—along with all the ] (], ], ], ]s), ], ], ]s and ].<ref>Robert W. Allan explores a few of these experiments on his webpage: | |||
| http://ww2.lafayette.edu/~allanr/mirror.html</ref> Most human children will pass the mirror test at 18 months old.<ref>, by Dr. Jack Palmer, retrieved March 17, 2006.</ref> However, the usefulness of this test as a true test of consciousness has been disputed, and this may be a matter of degree rather than a sharp divide. Monkeys have been trained to apply abstract rules in tasks.<ref> - retrieved July 29, 2006</ref> | |||
| The human brain perceives the external world through the ]s, and each individual human is influenced greatly by his or her experiences, leading to ] views of ] and the passage of time. Humans are variously said to possess ], ], and a mind, which correspond roughly to the mental processes of ]. These are said to possess qualities such as self-awareness, ], ], and the ability to perceive the relationship between ] and one's ]. The extent to which the mind constructs or experiences the outer world is a matter of debate, as are the definitions and validity of many of the terms used above. The philosopher of ] ], for example, argues that there is no such thing as a narrative centre called the "mind", but that instead there is simply a collection of sensory inputs and outputs: different kinds of "software" running in parallel.<ref>Dennett, Daniel (1991). ''Consciousness Explained''. Little Brown & Co, 1991, ISBN 0-316-18065-3.</ref> Psychologist ] argued that the mind is an explanatory fiction that diverts attention from environmental causes of behavior,<ref>Skinner, B.F. About Behaviorism 1974, page 74–75</ref> and that what are commonly seen as mental processes may be better conceived of as forms of covert verbal behavior.<ref>Skinner, B.F. ''About Behaviorism'', Chapter 7: Thinking</ref><ref>A thesis against which ] advanced a considerable polemic.</ref> | |||
| Humans study the more physical aspects of the mind and brain, and by extension of the nervous system, in the field of ], the more behavioral in the field of psychology, and a sometimes loosely defined area between in the field of psychiatry, which treats mental illness and behavioral disorders. Psychology does not necessarily refer to the brain or nervous system, and can be framed purely in terms of ] or ] theories of the mind. Increasingly, however, an understanding of brain functions is being included in psychological theory and practice, particularly in areas such as ], ], and ]. | |||
| The nature of thought is central to psychology and related fields. ] studies ], the ] underlying behavior. It uses ] as a framework for understanding the mind. Perception, learning, problem solving, memory, attention, language and emotion are all well researched areas as well. Cognitive psychology is associated with a school of thought known as ], whose adherents argue for an ] model of mental function, informed by ] and ]. Techniques and models from cognitive psychology are widely applied and form the mainstay of psychological theories in many areas of both research and applied psychology. Largely focusing on the development of the human mind through the life span, ] seeks to understand how people come to perceive, understand, and act within the world and how these processes change as they age. This may focus on intellectual, cognitive, neural, social, or ]. | |||
| Some philosophers divide consciousness into phenomenal consciousness, which is experience itself, and access consciousness, which is the processing of the things in experience.<ref name="Bl"> Ned Block: ''On a Confusion about a Function of Consciousness" in: ''The Behavioral and Brain Sciences'', 1995.</ref> Phenomenal consciousness is the state of being conscious, such as when they say "I am conscious." Access consciousness is being conscious ''of'' something in relation to abstract concepts, such as when one says "I am conscious of these words." Various forms of access consciousness include awareness, self-awareness, conscience, ], ], and ]. The concept of phenomenal consciousness, in modern history, according to some, is closely related to the concept of ]. ] links sociology with psychology in their shared study of the nature and causes of human social interaction, with an emphasis on how people think towards each other and how they relate to each other. The behavior and mental processes, both human and non-human, can be described through ], ], ], and ] as well. ] is an ] that investigates how humans and human ] interact with both their natural environment and the human ]. | |||
| ===Motivation and emotion=== | |||
| {{Main|Motivation|Emotion}} | |||
| ] is the driving force of desire behind all deliberate ] of humans. Motivation is based on emotion—specifically, on the search for ] (positive emotional experiences), and the avoidance of conflict. Positive and negative is defined by the individual brain state, which may be influenced by ]s: a person may be driven to ] or ] because their ] is conditioned to create a positive response to these actions. Motivation is important because it is involved in the performance of all learned responses. Within ], ] and the ] are seen to be primary motivators. Within ], motivation is often seen to be based on ]s; these may be ], ], or ]. ]s generally posit divine or ]ic influences. | |||
| ], or the state of being happy, is a human emotional condition. The definition of happiness is a common ] topic. Some people might define it as the best condition that a human can have—a condition of ] and physical ]. Others define it as ] from want and distress; consciousness of the ] order of things; assurance of one's place in the ] or ]. | |||
| Emotion has a significant influence on, or can even be said to control, human behavior, though historically many ]s and ]s have for various reasons discouraged allowing this influence to go unchecked. Emotional experiences perceived as pleasant, such as ], admiration, or joy, contrast with those perceived as unpleasant, like ], ], or ]. There is often a distinction made between refined emotions that are socially learned and ] oriented emotions, which are thought to be innate. Human exploration of emotions as separate from other neurological phenomena is worthy of note, particularly in cultures where emotion is considered separate from physiological state. In some cultural medical theories emotion is considered so synonymous with certain forms of physical health that no difference is thought to exist. The ] believed excessive emotion was harmful, while some ] teachers (in particular, the poet and astronomer ]) felt certain extreme emotions could yield a conceptual perfection, what is often translated as ]. | |||
| In modern scientific thought, certain refined emotions are considered a complex neural trait innate in a variety of ] and non-domesticated ]s. These were commonly developed in reaction to superior survival mechanisms and intelligent interaction with each other and the environment; as such, refined emotion is not in all cases as discrete and separate from natural neural function as was once assumed. However, when humans function in civilized tandem, it has been noted that uninhibited acting on extreme emotion can lead to social disorder and ]. | |||
| ===Sexuality and love=== | |||
| {{Main|Love|Human sexuality}} | |||
| ], besides ensuring biological ], has important social functions: it creates physical intimacy, bonds, and hierarchies among individuals; may be directed to spiritual transcendence (according to some traditions); and in a ] sense to the enjoyment of activity involving sexual gratification. Sexual desire, or ], is experienced as a bodily urge, often accompanied by strong emotions such as love, ] and jealousy. The extreme importance of sexuality in the human species can be seen in a number of physical features, among them hidden ovulation, the evolution of external scrotum and penis suggesting sperm competition, the absence of an ], permanent ], the forming of pair bonds based on sexual attraction as a common social structure and sexual ability in females outside of ovulation. These adaptations indicate that the importance of sexuality in humans is on a par with that found in the ], and that the complex human sexual behaviour has a long ]ary history. | |||
| Human choices in acting on sexuality are commonly influenced by cultural norms, which vary widely. Restrictions are often determined by religious beliefs or social customs. The pioneering researcher ] believed that humans are born ], which means that any number of objects could be a source of pleasure. According to Freud, humans then pass through five stages of ] (and can fixate on any stage because of various traumas during the process). For ], another influential sex researcher, people can fall anywhere along a continuous scale of sexual orientation (with only small minorities fully ] or ]). Recent studies of neurology and genetics suggest people may be born with a predisposition to one sexual orientation or another.<ref> Buss, David M. (2004) "The Evolution of Desire: Strategies of Human Mating". Revised Edition. New York: Basic Books"</ref><ref> Thornhill, R., & Palmer, C. T. (2000). A Natural History of Rape. Biological Bases of Sexual Coercion. Cambridge: MIT Press.</ref> | |||
| ==Culture== | |||
| {{Social Infobox/Human}} | |||
| {{Main|Culture}} | |||
| ] is defined here as a set of distinctive material, intellectual, emotional, and spiritual features of a social group, including art, literature, ], lifestyles, value systems, traditions, rituals, and beliefs. The link between human biology and human behavior and culture is often very close, making it difficult to clearly divide topics into one area or the other; as such, the placement of some subjects may be based primarily on convention. Culture consists of values, social norms, and ]. A culture's ] define what it holds to be important or ethical. Closely linked are ], expectations of how people ought to behave, bound by tradition. Artifacts, or ], are objects derived from the culture's values, norms, and understanding of the world. | |||
| ===Language=== | |||
| {{Main|Language}} | |||
| The capacity humans have to transfer concepts, ideas and notions through speech and writing is unrivaled in known species. Unlike the call systems of other primates that are closed, human language is far more open, and gains variety in different situations. The human language has the quality of displacement, using words to represent things and happenings that are not presently or locally occurring, but elsewhere or at a different time.<ref name="Revolution"/> In this way data networks are important to the continuing development of language. The faculty of speech is a defining feature of humanity, possibly predating ] separation of the modern population. Language is central to the communication between humans, as well as being central to the sense of identity that unites nations, cultures and ethnic groups. The invention of writing systems at least 5,000 years ago allowed the preservation of language on material objects, and was a major step in cultural evolution. The science of ] describes the structure of language and the relationship between languages. There are approximately 6,000 different languages currently in use, including sign languages, and many thousands more that are considered ]. | |||
| ===Spirituality and religion=== | |||
| {{Main|Spirituality|Religion}} | |||
| ] is generally defined as a ] system concerning the supernatural, sacred or divine, and ]s, practices, values, institutions and rituals associated with such belief. The ] and the history of the ] have recently become areas of active scientific investigation.<ref>{{cite web|url=http://evolution.binghamton.edu/religion/|title=Evolutionary Religious Studies: A New Field of Scientific Inquiry}}</ref><ref>{{cite journal |author=Boyer P |title=Being human: Religion: bound to believe? |journal=Nature |volume=455 |issue=7216 |pages=1038–9 |year=2008 |month=October |pmid=18948934 |doi=10.1038/4551038a}}</ref><ref>{{Cite journal | last = R.F | year = 2003 | title = The psychology of religion | journal = Annual Review of Psychology | volume = 54 | issue = 1 | pages = 377–402 | doi = 10.1146/annurev.psych.54.101601.145024}}</ref> However, in the course of its ], religion has taken on many forms that vary by culture and individual perspective. Some of the chief questions and issues religions are concerned with include life after death (commonly involving belief in an ]), the ], the nature of the ] (]) and its ] (]), and what is ] or immoral. A common source in religions for answers to these questions are beliefs in ] ] beings such as ] or a singular ], although not all religions are ]—many are ] or ambiguous on the topic, particularly among the ]s. Spirituality, belief or involvement in matters of the ] or ], is one of the many different approaches humans take in trying to answer fundamental questions about humankind's place in the universe, the ], and the ideal way to live one's life. Though these topics have also been addressed by philosophy, and to some extent by science, spirituality is unique in that it focuses on ] or supernatural concepts such as ] and God. | |||
| Although the exact level of religiosity can be hard to measure,<ref>{{cite journal |author=Hall DE, Meador KG, Koenig HG |title=Measuring religiousness in health research: review and critique |journal=J Relig Health |volume=47 |issue=2 |pages=134–63 |year=2008 |month=June |pmid=19105008 |doi=10.1007/s10943-008-9165-2}}</ref> a majority of humans professes some variety of religious or spiritual belief, although some are ]: that is lacking or rejecting belief in the supernatural or spiritual. Other humans have no religious beliefs and are ], ], ] or simply ]. ] is a philosophy which seeks to include all of humanity and all issues common to humans; it is usually non-religious. Additionally, although most religions and spiritual beliefs are clearly distinct from science on both a philosophical and methodological level, the two are not generally considered mutually exclusive; a majority of humans holds a mix of both scientific and religious views. The distinction between philosophy and religion, on the other hand, is at times less clear, and the two are linked in such fields as the ] and ]. | |||
| ] on ] in ]]] | |||
| ===Philosophy and self-reflection=== | |||
| {{Main|Philosophy|Human self-reflection}} | |||
| {{See also|Human nature}} | |||
| ] is a discipline or field of study involving the investigation, analysis, and development of ideas at a general, abstract, or fundamental level. It is the discipline searching for a general understanding of reality, reasoning and values. Major fields of philosophy include ], ], ], ], and ] (which includes ] and ]). Philosophy covers a very wide range of approaches, and is used to refer to a ], to a perspective on an issue, or to the positions argued for by a particular philosopher or school of philosophy. | |||
| ===Art, music, and literature=== | |||
| {{Main|Art|Music|Literature}} | |||
| ] of a woman writing ] by ].]] | |||
| Artistic works have existed for almost as long as humankind, from early ] art to contemporary art. Art is one of the most unusual aspects of human behaviour and a key distinguishing feature of humans from other species. | |||
| As a form of ] expression by humans, art may be defined by the pursuit of ] and the usage of ]s of liberation and exploration (i.e. ], ], and ]) to mediate its boundaries. This distinction may be applied to objects or performances, current or historical, and its prestige extends to those who made, found, exhibit, or own them. In the modern use of the word, art is commonly understood to be the process or result of making material works that, from concept to creation, adhere to the "creative impulse" of human beings. Art is distinguished from other works by being in large part unprompted by necessity, by biological drive, or by any undisciplined pursuit of recreation. | |||
| Music is a natural ] phenomenon based on the three distinct and interrelated organization structures of rhythm, harmony, and melody. Listening to music is perhaps the most common and universal form of ] for humans, while learning and understanding it are popular ]s. There are a wide variety of ]s and ]s. ], the body of written—and possibly oral—works, especially creative ones, includes prose, poetry and drama, both fiction and ]. Literature includes such genres as ], legend, myth, ballad, and folklore. | |||
| ===Tool use and technology=== | |||
| {{Main|Tool|Technology}} | |||
| ] stone tool]] | |||
| Stone tools were used by proto-humans at least 2.5 million years ago.<ref>{{cite journal |author=Clark JD, de Heinzelin J, Schick KD, ''et al.'' |title=African Homo erectus: old radiometric ages and young Oldowan assemblages in the Middle Awash Valley, Ethiopia |journal=Science (journal) |volume=264 |issue=5167 |pages=1907–10 |year=1994 |month=June |pmid=8009220 |doi=10.1126/science.8009220 |url=}}</ref> The ] began around 1.5 million years ago. Since then, humans have made major advances, developing complex technology to create tools to aid their lives and allowing for other advancements in culture. Major leaps in technology include the discovery of ] - what is known as the ]; and the invention of automated machines in the ]. In modern times, the invention of the ] has allowed humans to share information faster than ever before. The use of ] as power is vital in the modern human world. | |||
| ] attempts to tell the story of past or lost cultures in part by close examination of the ] they produced. Early humans left ], ] and ] that are particular to various regions and times. | |||
| ===Race and ethnicity=== | |||
| {{Refimprove|date=June 2009}} | |||
| {{Main|Race (classification of human beings)|Ethnic group}} | |||
| {{See also|Race and genetics|Historical definitions of race}} | |||
| Humans often categorize themselves in terms of ] or ], sometimes on the basis of differences in appearance. Human racial categories have been based on both ] and visible ], especially facial features, ] and hair texture. Most current ] and archaeological evidence supports a ] of modern humans in ].<ref>{{cite journal | author = Hua Liu, et al. | title = A Geographically Explicit Genetic Model of Worldwide Human-Settlement History | url = http://www.journals.uchicago.edu/AJHG/journal/issues/v79n2/43550/43550.html | journal = The American Journal of Human Genetics | volume = 79 | pages = 230–237 | year = 2006 | doi = 10.1086/505436 | format = {{Dead link|date=June 2008}} – <sup></sup>}}</ref> Current genetic studies have demonstrated that humans on the African continent are most genetically diverse.<ref>{{cite journal | author = Jorde L, Watkins W, Bamshad M, Dixon M, Ricker C, Seielstad M, Batzer M | title = The distribution of human genetic diversity: a comparison of mitochondrial, autosomal, and Y-chromosome data | url= | journal = Am J Hum Genet | volume = 66 | issue = 3 | pages = 979–88 | year = 2000 | pmc=1288178 | pmid = 10712212 | doi = 10.1086/302825}}</ref> However, compared to many other animals, human gene sequences are remarkably homogeneous.<ref name="REGWG">{{cite journal |author= |title=The use of racial, ethnic, and ancestral categories in human genetics research |journal=Am. J. Hum. Genet. |volume=77 |issue=4 |pages=519–32 |year=2005 |month=October |pmid=16175499 |pmc=1275602 |doi=10.1086/491747 |url=}}</ref><ref>{{cite journal |author=Bamshad M, Wooding S, Salisbury BA, Stephens JC |title=Deconstructing the relationship between genetics and race |journal=Nat. Rev. Genet. |volume=5 |issue=8 |pages=598–609 |year=2004 |month=August |pmid=15266342 |doi=10.1038/nrg1401 |url=}}</ref><ref>{{cite journal |author=Tishkoff SA, Kidd KK |title=Implications of biogeography of human populations for 'race' and medicine |journal=Nat. Genet. |volume=36 |issue=11 Suppl |pages=S21–7 |year=2004 |month=November |pmid=15507999 |doi=10.1038/ng1438 |url=}}</ref><ref>{{cite journal |author=Jorde LB, Wooding SP |title=Genetic variation, classification and 'race' |journal=Nat. Genet. |volume=36 |issue=11 Suppl |pages=S28–33 |year=2004 |month=November |pmid=15508000 |doi=10.1038/ng1435 |url=}}</ref> The predominance of genetic variation occurs ''within'' racial groups, with only 5 to 15% of total variation occurring ''between'' groups.<ref>{{cite journal | author = | title = The use of racial, ethnic, and ancestral categories in human genetics research | url= | journal = Am J Hum Genet | volume = 77 | issue = 4 | pages = 519–32 | year = 2005 | pmid = 16175499 |pmc=1275602 | doi = 10.1086/491747}}</ref> Ethnic groups, on the other hand, are more often linked by linguistic, cultural, ancestral, and national or regional ties. Self-identification with an ethnic group is based on ]. Race and ethnicity can lead to variant treatment and impact ], giving rise to ] and the theory of ]. | |||
| There is no scientific consensus of a list of the human races, and few anthropologists endorse the notion of human "race".<ref>"Human Races: A Genetic and Evolutionary Perspective", Alan R. Templeton, American Anthropologist, New Series, Vol. 100, No. 3 (Sep., 1998), pp. 632-650</ref> For example, a ] includes the following in a classification of human races: Black (e.g. Sub-Saharan Africa), Red (e.g. Native Americans), Yellow (e.g. East Asians) and White (e.g. Europeans). | |||
| ===Society, government, and politics=== | |||
| ] complex in ], which houses one of the largest political organizations in the world.]] | |||
| {{Main|Society|Government|Politics|Sovereign state}} | |||
| ] is the system of organizations and institutions arising from interaction between humans. A ] is an organized ] community occupying a definite territory, having an organized ], and possessing internal and external ]. Recognition of the state's claim to independence by other states, enabling it to enter into international agreements, is often important to the establishment of its statehood. The "state" can also be defined in terms of domestic conditions, specifically, as conceptualized by ], "a state is a human community that (successfully) claims the monopoly of the 'legitimate' use of physical force within a given territory."<ref>, by ], 1918, retrieved March 17, 2006.</ref> | |||
| ] can be defined as the ] means of creating and enforcing ]s; typically via a ] ]. ] is the process by which decisions are made within groups. Although the term is generally applied to behavior within ]s, politics is also observed in all human group interactions, including corporate, academic, and religious institutions. Many different political systems exist, as do many different ways of understanding them, and many definitions overlap. The most common form of government worldwide is a ],{{Citation needed|date=December 2008}} however other examples include ], ], ], and ]. All of these issues have a direct relationship with economics. | |||
| ===War=== | |||
| {{Main|War}} | |||
| ] immediately killed over 120,000 humans.]] | |||
| War is a state of widespread conflict between states or other large groups of humans, which is characterized by the use of lethal ] between combatants and/or upon civilians. It is estimated that during the 20th century between 167 and 188 million humans died as a result of war.<ref>Ferguson, Niall. "The Next War of the World." Foreign Affairs, Sep/Oct 2006</ref> A common perception of war is a series of ]s between at least two opposing sides involving a dispute over ], territory, ], ], or other issues. A war between internal elements of a state is a ]. | |||
| There have been a wide variety of ] ] throughout the history of war, ranging from ] to ] to ] and ]. Techniques include ], the use of ], and ]. Military intelligence has often played a key role in determining victory and defeat. Propaganda, which often includes information, slanted opinion and disinformation, plays a key role in maintaining unity within a warring group, and/or sowing discord among opponents. In modern warfare, ] and ]s are used to control the land, warships the sea, and aircraft the sky. These fields have also overlapped in the forms of marines, paratroopers, naval aircraft carriers, and surface-to-air missiles, among others. Satellites in low Earth orbit have made outer space a factor in warfare as well, although no actual warfare is currently known to be carried out in space. | |||
| ===Trade and economics=== | |||
| ] | |||
| {{Main|Trade|Economics}} | |||
| Trade is the voluntary exchange of goods and services, and is a form of ]. A mechanism that allows trade is called a ]. The original form of trade was ], the direct exchange of goods and services. Modern traders instead generally negotiate through a medium of exchange, such as money. As a result, buying can be separated from selling, or ]. The invention of money (and later ], paper money and non-physical money) greatly simplified and promoted trade. Because of specialization and ], most people concentrate on a small aspect of manufacturing or service, trading their labour for products. Trade exists between regions because different regions have an ] or ] in the production of some tradable commodity, or because different regions' size allows for the benefits of ]. | |||
| Economics is a ] which studies the production, distribution, trade, and consumption of goods and services. Economics focuses on measurable variables, and is broadly divided into two main branches: ], which deals with individual agents, such as households and businesses, and macroeconomics, which considers the economy as a whole, in which case it considers ] and ] for money, ] and ]. Aspects receiving particular attention in economics are ], production, distribution, trade, and ]. Economic logic is increasingly applied to any problem that involves choice under scarcity or determining economic ]. Mainstream economics focuses on how prices reflect ], and uses equations to predict consequences of decisions. | |||
| ==References== | |||
| {{reflist|2}} | |||
| * Freeman, Scott; Jon C. Herron, ''Evolutionary Analysis'' (4th ed.) Pearson Education, Inc., 2007. ISBN 0-13-227584-8 pages 757-761. | |||
| ==External links== | |||
| {{Sisterlinks|Humans}} | |||
| {{wikispecies|Homo sapiens sapiens}} | |||
| {{Commons category|Homo sapiens}} | |||
| {{portal|Mammals|Okapi2.jpg}} | |||
| * | |||
| * | |||
| * Possible human-orangutan split 20 million years ago. (Aug 26 2007) | |||
| * {{eol|327955}} | |||
| {{Human|hide}} | |||
| {{Human Evolution}} | |||
| {{Hominidae nav}} | |||
| {{Apes}} | |||
| {{Link FA | de}} | |||
| {{Link FA | id}} | |||
| {{Link FA | ja}} | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| {{Link FA|eu}} | |||
| {{Link FA|id}} | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
| ] | |||
Revision as of 02:48, 17 November 2009
Humans are the best things in the world! Te best humans are Gracie and Billie!!!