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Human beings define themselves in biological, social, and spiritual terms. Biologically, humans are classified as the species Homo sapiens (Latin for "wise man" or "clever human"): a bipedal primate belonging to the superfamily of Hominoidea, with all of the apes: chimpanzees, bonobos, gorillas, orangutans, and gibbons.

Humans have an erect body carriage that frees the upper limbs for manipulating objects, a highly developed brain and consequent capacity for abstract reasoning, speech, language, and introspection. One current hypothesis within the scientific community is that the human evolution of bipedalism (two-legged locomotion) occurred in response to a need for long-distance running. Humans are said to be one of a short list of animals with such a capacity.

The human mind has several distinct attributes. It is responsible for the complexity of human behaviour, especially language. Curiosity and observation have led to a variety of explanations for consciousness and the relation between mind and body. Psychology, especially neuropsychology, attempts to study them from the scientific point of view. Religious perspectives generally emphasise a soul, qi or atman as the essence of being, and are often characterised by the belief in and worship of God, gods or spirits. Philosophy, especially philosophy of mind, attempts to fathom the depths of each of these perspectives. Art, music and literature are often used in expressing these concepts and feelings.

Humans are inherently social. Humans create complex social structures composed of many co-operating and competing groups. These range from nations and states down to families, and also from the community to the self. Seeking to understand and manipulate the world around us led to the development of technology and science as a social, rather than an individual, enterprise. These institutions have given rise to shared artefacts, beliefs, myths, rituals, values, and social norms which form the group's culture.

Beliefs about humans

There are a number of perspectives regarding the fundamental nature and substance of humans. These are by no means mutually exclusive, and the list is by no means exhaustive.

  • Materialism holds that humans are physical beings without any supernatural or spiritual component. Materialism holds to naturalism and rejects supernaturalism.
  • The Abrahamic religions sometimes hold that humans are both physical and spiritual in nature, and were deliberately created in the image of God, sometimes that humans are wholly physical (but possibly that they will enter a different state at some point in the future after the world is ended).
  • Pantheism holds that human beings, as part of the world, are a part of God, who is identified with the world (and vice versa). (Panentheism is similar, but holds that the world is God, but that God is more than the world.) Monism, animism, Vedic religion, and other forms of Eastern philosophy have related beliefs.

The word people

In general, the word people is a collective or plural term for any specific group of individual persons.

However, when used to refer to a group of humans possessing a common ethnic, cultural or national unitary characteristic or identity, people is a singular count noun, and as such takes an "s" in the plural (examples: the English-speaking peoples of the world, the indigenous peoples of Brazil).

Terminology

Juvenile males are called boys, adult males men, juvenile females girls, and adult females women. Humans are commonly referred to as persons or people and collectively as Man (capital M), mankind, humanity, or the human race. Until the 20th century, human was only used adjectivally ("pertaining to mankind"). Nominal use of human (plural humans) is short for human being, and used not to be considered good style in traditional English grammar. As an adjective, human is used neutrally (as in human race), but human and especially humane may also emphasise positive aspects of human nature, and can be synonymous with benevolent (versus inhumane; c.f. humanitarian).

A distinction is maintained in philosophy and law between the notions "human being", or "man", and "person". The former refers to the species, while the latter refers to a rational agent (see, for example, John Locke's Essay concerning Human Understanding II 27 and Immanuel Kant's Introduction to the Metaphysic of Morals). The term "person" is thus used of non-human animals, and could be used of a mythical being, an artificial intelligence, or an extraterrestrial. An important question in theology and the philosophy of religion concerns whether God is a person. (See also Great ape personhood.)

In Latin, humanus is the adjectival form of the noun homo, translated as "man" (to include males and females). The Old English word man could also have this generic meaning, as demonstrated by such compounds as wifman (“female person”) → wimanwoman. For the etymology of man see mannaz.

Classification and evolution

Map of early human migrations according to mitochondrial population genetics (numbers are millennia before present).

Biologically, humans are defined as hominids of the species Homo sapiens, of which the only extant subspecies is Homo sapiens sapiens. They are usually considered the only surviving species in the genus Homo, although some argue that the two species of chimpanzees should be reclassified from Pan troglodytes and Pan paniscus to Homo troglodytes and Homo paniscus, given their sharing a recent ancestor with man. [3]

Partial genome sequencing resulted in these conclusions: "[C]himps, gorillas, and humans form a clade of closely related species; orangutans are slightly less close phylogenetically, and gibbons are a more distant branch." [4] "To study the genomic divergences among hominoids [we] sequenced [DNA] in a human, a chimpanzee, a gorilla, and an orangutan. The average sequence divergence was only 1.24% ± 0.07% for the human-chimpanzee pair, 1.62% ± 0.08% for the human-gorilla pair, and 1.63% ± 0.08% for the chimpanzee-gorilla pair. [...] The average sequence divergences between orangutans and humans, chimpanzees, and gorillas were 3.08% ± 0.11%, 3.12% ± 0.11%, and 3.09% ± 0.11%, respectively." [5]

Full genome sequencing resulted in these conclusions: "After 6 [million] years of separate evolution, the differences between chimp and human are just 10 times greater than those between two unrelated people and 10 times less than those between rats and mice." Chimp and human DNA is 96% identical

It has been estimated that the human lineage diverged from that of chimpanzees about five million years ago, and from gorillas about eight million years ago. However, in 2001 a hominine skull approximately seven million years old, classified as Sahelanthropus tchadensis, was discovered in Chad and seems to indicate an earlier divergence from the ape lineage.

Two prominent theories of the evolution of contemporary humans exist. They concern the relationship between modern humans and other hominids. The single-origin hypothesis proposes that modern humans evolved in Africa and later replaced hominids in other parts of the world. The multiregional hypothesis proposes that modern humans evolved at least in part from independent hominid populations. DNA evidence supports an African origin for the maternal and paternal lineages of contemporary humans. An unintuitive complication for this debate is that the evolutionary lineage of an individual may differ from the evolutionary history of each of an individual's genes (see most recent common ancestor). An emerging synthesis theory proposes that the genes of contemporary humans are predominantly descendent from a recent African origin, but that interbreeding and assimilation with other hominids may have contributed genes to local populations (Templeton, 2002). Eswaran et al. (2005) speculate that "as much as 80% of the nuclear genome is significantly affected by assimilation from archaic humans (i.e., 80% of loci may have some archaic admixture, not that the human genome is 80% archaic)."

Human evolution is characterised by a number of important trends :

  • expansion of the brain cavity and brain itself, which is typically 1,400 cm³ in volume, over twice that of a chimpanzee or gorilla. The pattern of human postnatal brain growth differs from that of other apes (heterochrony), allowing for an extended period of social learning in juvenile humans. Physical anthropologists argue that a reorganisation of the structure of the brain is more important than cranial expansion itself;
  • canine tooth reduction;
  • bipedal locomotion;
  • descent of the larynx, which makes speech possible.

How these trends are related and what their role is in the evolution of complex social organisation and culture are matters of ongoing debate.

During the 1990s, variations in human mitochondrial DNA were recognised as a valuable source for reconstructing the human "family tree" and for tracing early human migrations. As a result, the ancestors of all modern humans are thought to have evolved in Africa over 150,000 years ago; modern humans began to move out of Africa less than 100,000 years ago. Australia was colonised 70,000 years ago; Europe 40,000 years ago with later waves 22,000 and 9,000 years ago, according to Ornello Semino of the University of Pavia and Peter Underhill of Stanford University [6]; and the Americas 30,000 years ago, with a second colonisation from across the Pacific Ocean 15,000 years ago. (See Human migration.)

Since the human embryo normally takes its mitochondrial DNA from its mother's egg and not from the sperm, variations in human mitochondrial DNA provide a means of identifying those individuals who share a common matrilineal ancestor. A mathematical analysis of mitochondrial DNA from thousands of living individuals suggests that the matrilineal lines for the people analysed converges on one ancestor called Mitochondrial Eve (ME) who lived in Africa about 200,000 years ago. That is, ME is claimed to be the most recent common ancestor of all humans alive today with respect to matrilineal descent (Boyd and Silk 2003:389–99).

Some religious groups object to the theory of evolution: see creationism, argument from evolution, intelligent design, creation (theology).

Biology

Two young girls

Life cycle

The human life cycle is similar to that of other placental mammals. New human life develops from conception. An egg is usually fertilised inside the female by sperm from the male through sexual intercourse, though in vitro fertilisation methods are also used. The developing individual is first called a zygote. This is a single diploid cell, which means that it has two sets of 23 chromosomes, each set received from one parent. Most of them are autosomes, while two are sex chromosomes. One is maternal and is always X, the other is paternal and can be X or Y. The combination determines the sex of the future human being: XX means a girl, while XY means a boy. As the zygote grows through successive stages inside the female's uterus over a period of 38 weeks, it is called an embryo, then a foetus. At birth, the fully grown foetus, now called a baby, is expelled from the female's body and breathes independently for the first time. At this point, most modern cultures recognise the baby as a person entitled to the full protection of the law, though some jurisdictions extend personhood to human foetuses while they remain in the uterus.

Compared with that of other species, human childbirth is relatively complicated. Painful labours lasting twenty-four hours or more are not uncommon, and may result in injury to the child or the death of the mother, although the chances of a successful labour increased significantly during the twentieth century in wealthier countries. It remains an arguably more dangerous ordeal in remote, underdeveloped regions of the world, though the women who live in these regions have argued that their natural childbirth methods are safer and less traumatic for mother and child.

Human children are born after a nine-month gestation period, with typically 3–4 kilograms (6–9 pounds) in weight and 50–60 centimetres (20–24 inches) in height in developed countries. [7] Helpless at birth, they continue to grow for some years, typically reaching sexual maturity at 12–15 years of age. Boys continue growing for some time after this, reaching their maximum height around the age of 18. These values vary too, depending on genes and environment.

The human lifespan can be split into a number of stages: infancy, childhood, adolescence, young adulthood, maturity and old age, though the lengths of these stages, especially the later ones, are not fixed.

There are striking differences in life expectancy around the world. The developed world is quickly getting older, with the median age around 40 years (highest in Monaco at 45.1 years), while in the developing world, the median age is 15–20 years (the lowest in Uganda at 14.8 years). Life expectancy at birth is 77.2 years in the U.S. as of 2001. [8] The expected life span at birth in Singapore is 84.29 years for a female and 78.96 years for a male, while in Botswana, due largely to AIDS, it is 30.99 years for a male and 30.53 years for a female. One in five Europeans, but one in twenty Africans, is 60 years or older, according to The World Factbook. [9]

The number of centenarians in the world was estimated by the United Nations [10] at 210,000 in 2002. The maximum human life span is thought to be over 120 years. Worldwide, there are 81 men aged 60 or over for every 100 women, and among the oldest, there are 53 men for every 100 women.

The philosophical questions of when human personhood begins and whether it persists after death are the subject of considerable debate. The prospect of death may cause unease or fear. (See also near-death experience.) Burial ceremonies are characteristic of human societies, often inspired by beliefs in an afterlife. Institutions of inheritance or ancestor worship may extend an individual's presence beyond his physical lifespan (see immortality).

Anatomy and physiology

A human skeleton

{{main2|Human anatomy|Human physical appearance]], [[Human height}}

Humans exhibit fully bipedal locomotion. This leaves the forelimbs available for manipulating objects using opposable thumbs.

Humans vary substantially around the mean height and mean weight, which vary depending on locality and historical factors. Although body size is largely determined by genes, it is also significantly influenced by diet and exercise. The mean height of a North American adult female is 162 cm (5'4") and the mean weight is 62 kg (137 lb). North American adult males are typically larger: 175 cm (5'9") and 78 kilograms (172 lb).

Human skin is relatively hairless in comparison to other primates. The colour of human hair and skin is determined by the presence of coloured pigments called melanins. Most researchers believe that skin darkening was an adaptation that evolved as a defence against UV solar radiation; melanin is an effective sunblock. The skin colour of contemporary humans can range from very dark brown to very pale pink. It is geographically stratified and in general correlates with the environmental level of UV. Human skin and hair colour is controlled in part by the MC1R gene. For example, the red hair and pale skin of some Europeans is the result of mutations in MC1R. Human skin has a capacity to darken (sun tanning) in response to UV exposure. Variation in the ability to sun tan is also controlled in part by MC1R.

Because humans are bipedal, the pelvic region and spinal column tend to get worn, creating locomotion difficulties in old age.

Race and ethnicity

Humans categorise themselves and others in terms of race or ethnicity when it is useful to do so. Racial categories are more likely to be primarily based on biological qualities, such as skin colour, facial features, ancestry, and other genetic variances, with cultural and historical differences also an influence. Identification of ethnic groups, however, are more likely to primarily be based on cultural affiliations. When in human society race and ethnicity lead to variant treatment of people based on perceived differences, it is thought to impact on what is presently termed social identity, hence giving rise to the recent theory of identity politics in race and ethnicity. Ideologies of race or ethnicity are related to concepts of kinship and descent.

File:Map of skin hue equi.png
Map of skin-colour distribution for "native populations" collected by Renato Biasutti prior to 1940. Human skin colour can range from very dark brown to very pale pink in different people.

Although most humans recognise that variances occur within a species, it is often a point of dispute as to what these differences entail, and despite scientific findings that the human species is fairly similar in terms of brain size and functional capacity, discrimination by humans based on one's own race as opposed to another's (racism) is still very much an issue in the early twenty-first century.

Genetics

Humans are a eukaryotic species. A human has 46 chromosomes: (22 pairs of autosomes, and 2 sex chromosomes). At present estimate, humans have approximately 20,000–25,000 genes and share 95% of their DNA with their closest living evolutionary relatives, the common chimpanzee and the bonobo, or pygmy chimpanzee. [11] Like other mammals, humans have an XY sex determination system, so that females have the sex chromosomes XX and males have XY. The X chromosome is larger and carries many genes not on the Y chromosome, which means that recessive diseases associated with X-linked genes affect men more often than women. For example, genes that control the clotting of blood reside on the X chromosome. Women have a blood-clotting gene on each X chromosome so that one normal blood-clotting gene can compensate for a flaw in the gene on the other X chromosome. But men are hemizygous for the blood-clotting gene, since there is no gene on the Y chromosome to control blood clotting. As a result, men will suffer from haemophilia more often than women.

Intelligence

see below: Human Consciousness

Leonardo da Vinci's Vitruvian Man

Most humans consider their species to be the most intelligent species in the animal kingdom. Certainly, humans are the only technologically advanced animal. Along with neural complexity, the brain-to-body-mass ratio is generally assumed to be a good indicator of relative intelligence. Humans have the second highest brain-to-body-mass ratio or encephalization quotient (EQ) of all animals, with the tree shrew having the highest [12], and the bottlenose dolphin very similar to humans. (Sharks have the highest for a fish; and the octopus has the highest for an invertebrate.)

The human ability to abstract may be unparalleled in the animal kingdom. Human beings are one of five species to pass the mirror test – which tests whether an animal recognises its reflection as an image of itself – along with chimpanzees or bonobos, orangutans, and dolphins. Human beings under the age of four usually fail the test.

Emotion

Human emotion has a significant influence on, or can even be said to control, human behaviour. Emotional experiences perceived as pleasant, like love, admiration, or joy, contrast with those perceived as unpleasant, like hate, envy, or sorrow. There is often a distinction seen between refined emotions, which are socially learned, and survival oriented emotions, which are thought to be innate.

Human exploration of emotions as separate from other neurological phenomena is worth note, particularly in those cultures were emotion is considered separate from physiological state. In some cultural medical theories, to provide an example, emotion is considered so synonymous with certain forms of physical health that no difference is thought to exist. The Stoics believed excessive emotion was harmful, while some Sufi teachers (in particular, the poet and astronomer Omar Khayyám) felt certain extreme emotions could yield a conceptual perfection, what is often translated as ecstasy.

In modern scientific thought, certain refined emotions are considered to be a complex neural trait of many domesticated and a few non-domesticated mammals, developed commonly 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. Still, when humans function in civilised tandem, it has been noted that uninhibited acting on extreme emotion can lead to social disorder and crime.

Sexuality

Human sexuality, besides ensuring reproduction, has important social functions, creating bonds and hierarchies among individuals. Sexual desire is experienced as a bodily urge, often accompanied by strong emotions, both positive (such as love or ecstasy) and negative (such as jealousy). (See also Libido.)

Human sexuality is an integral part of the social life of humans, governed by implied rules of behaviour. Sexuality influences social norms and society in turn influences the manner in which sexuality can be expressed. Human sexual choices are usually made in reference to current cultural norms. For example, some choose to abstain from sex before marriage because of their religious beliefs, while others may not have such scruples. Most cultures, groups and individuals insist on monogamy, while some others practice polygamy or other forms of human sexuality. Acceptance of particular types of sexuality varies widely from culture to culture.

Body

The physical appearance of the human body is central to culture and art. In every human culture, people adorn their bodies with tattoos, cosmetics, clothing, and jewellery. Hairstyles and hair colour also have important cultural implications. The perception of an individual as physically beautiful or ugly can have profound implications for their lives. This is particularly true of women, whose external appearance is highly valued in most, if not all, human societies.

The individual need for regular intake of food and drink is prominently reflected in human culture. (See also food science.) Failure to obtain food leads to hunger and eventually starvation, while failure to obtain water leads to dehydration and thirst. Both starvation and dehydration cause death if not alleviated: human beings can survive for over two months without food, but only up to around 14 days without water. (See also famine, malnutrition).

The average sleep requirement is between seven and eight hours a day for an adult and nine to ten hours for a child. Elderly people usually sleep for six to seven hours. It is common, however, in modern societies for people to get less sleep than they need. (See also sleep deprivation.)

The human body is subject to an ageing process and to illness. Medicine is the science that explores methods of preserving bodily health.

Habitat

Template:Social Infobox/Human The conventional view of human evolution states that humans evolved in inland savanna environments in Africa. (See Human evolution, Vagina gentium, Environment of Evolutionary Adaptedness.) Technology has allowed humans to colonise all of the continents and adapt to all climates. Within the last few decades, humans have been able to explore Antarctica, the ocean depths, and space, although long-term habitation of these environments is not yet possible. Humans, with a population of about six billion, are one of the most numerous mammals on Earth.

Most humans (61%) live in the Asian region. The vast majority of the remainder live in the Americas (14%), Africa (13%) and Europe (12%), with only 0.3% in Australia. (See list of countries by population and list of countries by population density.)

The original human lifestyle is hunting-gathering, which is adapted to the savanna. Other human lifestyles are nomadism (often linked to animal herding) and permanent settlements made possible by the development of agriculture. Humans have a great capacity for altering their habitats by various methods, such as agriculture, irrigation, urban planning, construction, transport, and manufacturing goods.

Permanent human settlements are dependent on proximity to water and, depending on the lifestyle, other natural resources such as fertile land for growing crops and grazing livestock, or seasonally by populations of prey. With the advent of large-scale trade and transport infrastructure, immediate proximity to these resources has become unnecessary, and in many places these factors are no longer the driving force behind growth and decline of population.

Human habitation within closed ecological systems in hostile environments (Antarctica, outer space) is expensive, typically limited in duration, and restricted to scientific, military, or industrial expeditions. Life in space has been very sporadic, with a maximum of thirteen humans in space at any given time, in part because of human vulnerability to ionising radiation, starting with Yuri Gagarin's space flight in 1961. Between 1969 and 1974, up to two humans at a time spent brief intervals on the Moon. As of 2005, no other celestial body has been visited by human beings, although there has been a continuous human presence in space since the launch of the initial crew to inhabit the International Space Station on October 31, 2000.

Population

From 1800 to 2000, the human population increased from one to six billion. It is expected to crest at around ten billion during the 21st century. As of 2004, around 2.5 billion out of 6.3 billion people live in urban centres, and this is expected to rise during the 21st century. Problems for humans living in cities include various forms of pollution, crime, and poverty, especially in inner city and suburban slums.

Geneticists Lynn Jorde and Henry Harpending of the University of Utah have concluded that the variation in the total stock of human DNA is minute compared to that of other species; and that around 74,000 years ago, human population was reduced to a small number of breeding pairs, possibly as small as 1000, resulting in a very small residual gene pool. Various reasons for this bottleneck have been postulated, the most popular being the eruption of a volcano called Toba. (See the Toba catastrophe theory.)

Human extinction

Human extinction refers to the possibility that the human species may become extinct, either through its own actions (for example, because of pollution or the use of nuclear weapons) or because of a natural disaster.

Consciousness

See main article Consciousness
File:Consciousness-brain.jpg
The human brain and the seat of consciousness, courtesy of Dr. Rhawn Joseph. [1]

The way the world is experienced by an individual is the subject of much debate and research in Philosophy of mind, psychology, brain biology, neurology, and cognitive science. Human and non-human animals are said to possess consciousness, self-awareness, or a mind, which gives rise to an individual's perception of his own existence, the passage of time, and his free will, though within philosophy there is a quarrel as to the nature of free will, the very definition of free will, and whether it exists or not. There can be considered relative free will, which is sometimes explained as the inability of our imperfect minds to understand the fixed destiny of the universe, and absolute free will, which can usually be proven only by spiritual or other unscientific methods of inquiry.

There are many debates about the extent to which the mind constructs, rather than simply experiences, the outer world, and whether the concept of mind even makes sense. Cognitive scientist Daniel Dennett, for example, argues that there is no such thing as a narrative centre called mind, but that instead there is simply a collection of sensory inputs and outputs: different kinds of software running in parallel (Dennett, 1991).

Mind

File:SigmundFreud2.jpg
Sigmund Freud

Consciousness is in some way the product or purpose of the mind. Explanations of the nature of the mind and of its relation to the body and the world have been many and various.

Adi Shankara in the East proposed Advaita Vedanta, a popular argument for monism (the metaphysical view that all is of one essential essence, substance or energy).

Another type of Monism is Physicalism or materialism, which holds that only the physical is real, and that the mental can be reduced to the physical. So organs such as the brain are made of tissues, which in turn are made of cells, which are made of atoms; the mind is on this account no more than the product of the action of these atoms.

Idealism and phenomenalism, on the contrary, assert the existence of the mind and deny, or at the least deny the importance of, an external reality that exists independently of the mind.

René Descartes proposed that both mind and matter exist, and that the one cannot be reduced to the other. This philosophical position is called dualism. Dvaita is the Hindu philosophy incorporating dualism.

Johannes Jacobus Poortman proposed a Pluralist classification of a number of different mystical and metaphysical views. Vishishtadvaita is the Hindu philosophy incorporating pluralism.

Many religions hold that humans have both a body and a soul, usually proposing that the soul can in some way survive the death of the body. Although the soul is often equated with the mind, this is not always the case.

Of course, there are still others, such as those who believe scientific method and modern technology allows successful exploration and understanding of the physical universe inclusive of the human brain, who are sceptical as to the independent function of human consciousness without organic function of the brain.

Psyche

File:Idegosuperego.gif
Freud's concept of the mind, courtesy of All-Psych Online [2]

The science of psychology studies the human psyche. The term psyche describes the mental and emotional attributes of an individual or group.

One branch of psychology, psychoanalysis, devised by Sigmund Freud and expanded and refined by Carl Jung and others, reveals through frequent individual psychotherapy sessions portions of what it calls the unconscious mind.

The Swiss psychiatrist Carl Gustav Jung, initially one of Freud's followers and friends, founded the school of analytical psychology and introduced the notion of the collective unconscious, a term taken from philosophy and used by Jung to describe symbols or archetypes that he believed might be common to all cultures.

Many divide the mind into the id (an individual's basic needs and instincts), the superego (personal and cultural values and norms), and the ego (the central, organising self, whose job it is to satisfy the id but not upset the superego). [13] (See also Ego, Superego and Id.)

There is also the Conscious, Subconscious, and Superconsciousness, a related but not identical set of categories.

Self-reflection and Humanism

File:Thinker.png
The Thinker by Auguste Rodin: An artist's impression of "Homo sapiens"

Thales of Miletus, when asked what was difficult, answered in a well-known apophthegm: "To Know Thyself" γνῶθι σεαυτόν (also attributed to Socrates, and inscribed on the Temple of Apollo at Delphi).

Humans often consider themselves to be the dominant species on Earth, and the most advanced in intelligence and ability to manage their environment. This belief is especially strong in Western culture, and is derived in part from the Hebrew Bible's creation story in which Adam is explicitly given dominion over the Earth and all of its creatures. Alongside such claims of dominance we often find radical pessimism because of the frailty and brevity of human life. In the Hebrew Bible, for example, dominion of man is promised in Genesis 1:28, but the author of Ecclesiastes bewails the vanity of all human effort.

The Ancient Greek philosopher Protagoras made the famous claim that "Man is the measure of all things; of what is, that it is; of what is not, that it is not." Aristotle describes man as the "communal animal" (ζῷον πολιτικόν), i.e. emphasising society-building as a central trait of human nature, and "animal with sapience" (ζῷον λόγον ἔχων, animal rationale), a term that also inspired the species' taxonomy, Homo sapiens. This philosophy is today called "Humanism".

Unique human characteristics

From a scientific viewpoint, Homo sapiens certainly is among the most generalised species on Earth, and few single species occupy as many diverse environments as humans. Various attempts have been made to identify a single behavioural characteristic that distinguishes humans from all other animals, e.g. the ability to make and use tools, the ability to alter the environment, language use, and the development of complex social structures. Some anthropologists think that these readily observable characteristics (tool-making and language) are based on less easily observable mental processes that might be unique among humans: the ability to think symbolically, in the abstract or logically. Others, that our capacity for symbolic thought is a development from our capacity to manipulate tools and/or the development of speech. It is difficult, however, to arrive at a set of attributes that includes all humans, and humans only, and the wish to find unique human characteristics is a matter of Anthropocentrism more than one of zoology.

Culture

File:Cavehand.jpg
Cave art

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.

Culture consists of at least three elements: values, social norms, and artefacts. A culture's values define what it holds to be important. Norms are expectations of how people ought to behave. Artefacts – things, or material culture – derive from the culture's values and norms together with its understanding of the way the world functions.

Language

Values, norms and technology are dependent on the capacity for humans to share ideas. The faculty of speech may be a defining feature of humanity, probably predating phylogenetic separation of the modern population. (See Proto-World language, Origins of language.) Language is central to the communication between humans. Some scientists argue that non-human animals are able to use language too, and that non-human primates are able to learn human sign language [14] [15] (pdf). Language is central to the sense of identity that unites cultures and ethnicities.

The invention of writing systems some 5000 years ago, allowing the preservation of speech, was a major step in cultural evolution. Language, especially written language, is sometimes thought to have supernatural status or powers. (See Magic, Mantra, Vac.)

The science of linguistics describes the structure of language and the relationship between languages. There are estimated to be some 6,000 different languages, including sign languages, used today.

Artefacts, technology and science

{{main2|Archaeology|Technology]], Science, [[Civilisation}} Human cultures are both characterised and differentiated by the objects that they make and use. Archaeology attempts to tell the story of past or lost cultures in part by close examination of the artefacts they produced. Early humans left stone tools, pottery and jewellery that are particular to various regions and times.

Improvements in technology are passed from one culture to another. For instance, the cultivation of crops arose in several different locations, but quickly spread to be an almost ubiquitous feature of human life. Similarly, advances in weapons, architecture and metallurgy are quickly disseminated.

Such techniques can be passed on by oral tradition. The development of writing, itself a type of artefact, made it possible to pass information from generation to generation and from region to region with greater accuracy.

Together, these developments made possible the commencement of civilisation and urbanisation, with their inherently complex social arrangements. Eventually this led to the institutionalisation of the development of new technology, and the associated understanding of the way the world functions. This Science now forms a central part of human culture.

Religion and philosophy

Religion and philosophy are aspects of human culture and view the position of humans, in relation to supernatural entities and other living beings, differently.

Animism is the belief that objects and ideas including other animal species, tools, and natural phenomena have or are expressions of living spirits.

Rituals in animistic cultures are often performed by shamans or priests, who are usually seen as possessing spiritual powers greater than or external to the normal human experience.

Mysticism views humans as susceptible to an ineffable experience or realisation of unity with the Absolute.

In polytheistic religions, humans are mainly characterised by their inferiority to the gods, sometimes reflected in a hierarchical society ruled by dynasties that claim divine descent.

Monotheism generally believes that a single deity, who is either the only one in existence, or who incorporates or excels all lesser deities, created humanity. Humans are thus bound by filial and moral duty, and cared for by paternal providence. In all Abrahamic religions (Judaism, Christianity, and Islam), humans are lord, or steward, over the earth and all its other creatures.

Monism is the metaphysical view that all is of one essential essence, substance or energy. Monistic theism, a variant of both monism and Monotheism, views God as both Immanent and Transcendent. Both are dominant themes in Hinduism, that holds humans special in that they can conceptualise God and strive to achieve him, but their soul is akin to a divine spark just as an animal's is.

Humanism as a philosophy defines a socio-political doctrine the bounds of which are not constrained by those of locally developed cultures, but which seeks to include all of humanity and all issues common to human beings. Because spiritual beliefs of a community often manifests as religious doctrine, the history of which is as factious as it is unitive, secular humanism grew as an answer to the need for a common philosophy that transcended the cultural boundaries of local moral codes and religions. Many humanists are religious, however, and see humanism as simply a mature expression of a common truth present in most religions. Humanists affirm the possibility of an objective truth and accept that human perception of that truth is imperfect. The most basic tenets of humanism are that humans matter and can solve human problems, and that science, freedom of speech, rational thought, democracy, and freedom in the arts are worthy pursuits or goals for all peoples. Modern humanism depends on reason and logic and rejects the supernatural.

See also: Atheism, Atman, Conscience, Ecstasy (state), Ethics, God, Humanism, Human realm, Incarnation, Karma, Korban, Morality, Mystic, Prayer, Rationalism, Reincarnation, Religion and New religious movements, Resurrection, Ritual, Sacrifice, Salvation, Sin, Soul, Spirituality, Surat Shabda Yoga, Worship

See also

References

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Further reading

  • A Look at Modern Human Origins by C. David Kreger.
  • Homo Sapiens Tree of Life web project
  • "Why Humans and Their Fur Parted Ways" by Nicholas Wade, New York Times, August 19, 2003.
  • 3-D Brain Anatomy, "The Secret Life of the Brain," Public Broadcasting Service, retrieved April 3, 2005
  • Human evolution: the fossil evidence in 3D by Philip L. Walker and Edward H. Hagen, Dept of Anthropology, University of California, Santa Barbara, retrieved April 5, 2005
  • Dobzhansky, Theodosius. 1963. "Anthropology and the natural sciences-The problem of human evolution," Current Anthropology 4 (2): 138-148.
  • Jablonski, N.G. & Chaplin, G. 2000. "The evolution of human skin coloration." Journal of Human Evolution 39: 57-106. [17] (pdf)
  • Robin, Ashley. 1991. Biological Perspectives on Human Pigmentation. Cambridge: Cambridge University Press.
  • Sagan, Carl. 1978. The Dragons of Eden, A Balantine Book, ISBN 0345346297