Human

For other uses, see Human (disambiguation).

Human beings define themselves in biological, social, and spiritual terms. Biologically, humans are classified as the species Homo sapiens (Latin for "knowing man"): a bipedal primate belonging to the superfamily of Hominoidea, with all of the apes: chimpanzees, 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. A concept current within the scientific community is that human evolution 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 the relation between mind and body. Among these are the science of psychology, religious perspectives emphasizing a soul, Qi or atman as the essence of being, and philosophy, especially philosophy of mind, which 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 cooperating 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 artifacts, 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.
Abrahamic religion holds that humans are both physical and spiritual in nature, and were deliberately created in the image of God.
Pantheism holds that human beings, as spiritual being interwoven into a spiritual universe, are a part of God, who is completely immanent. Panentheism is similar, but holds that God is transcendent as well as immanent. Monism, Animism, Vedic and other forms of Eastern philosophy have related beliefs.

The word people

In general, the English 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

In the English language, 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, 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 emphasize 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”) → wiman → woman. For the etymology of man see mannaz.

Classification and evolution

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File:Human mtDNA migration.png

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]

The closest surviving relatives of humans are chimpanzees, the second closest bonobos, the third orangutans. Together with gorillas, these four make up the category of great apes. 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 hominds. The single-origin hypothesis proposes that modern humans evolved in Africa and later replaced hominds 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. A 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 human are predominantly decendent from a recent African origin, but that interbreeding with other hominds 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 characterized 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, although physical anthropologists argue that a reorganization 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 organization and culture, are matters of ongoing debate.

During the 1990s, variations in human mitochondrial DNA were recognized 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 colonized 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 [4]; and the Americas 30,000 years ago, with a second colonization 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 analyzed 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 2003:389-399).

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

Biology

Life cycle

The human life cycle is similar to that of other placental mammals. New human life develops from conception. An egg is usually fertilized inside the female by sperm from the male through sexual intercourse, though in vitro fertilization 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 fetus. At birth, the fully grown fetus, now called a baby, is expelled from the female's body, and breathes independently 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 personhood to human fetuses while they remain in the uterus.

Compared with that of other species, human childbirth is relatively complicated. Painful labors 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 labor 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. [5] 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. [6] 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. [7]

The number of centenarians in the world was estimated by the United Nations [8] 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 persist 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

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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).

File:Map of skin hue equi.png

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

Human skin is relatively hairless in comparison to other apes. The loss of hair in early humans was complemented by the darkening of human skin color. The color of human hair and skin is determined by the presence of colored pigments called melanins. Most researchers believe that skin darkening was an adaptation that evolved as a defense against UV solar radiation; melanin is an effective sunblock. The skin color 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. While the darkening of skin among humans in the tropics is likely the result of natural selection, it is less definite that the lightening of skin (e.g., among Europeans) is the result of selection. Human skin and hair color 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. On average, women have slightly lighter skin than men.

Because humans are bipedal, the pelvic region and spinal column tend to get worn, creating locomotion difficulties in old age. Humans are also more likely than other primates to suffer from obesity because of poor diet and lack of exercise.

Race and ethnicity

Template:Seemain2 Some categorize themselves and others humans in terms of race or ethnicity. Racial categories are based on biological qualities, such as skin color, facial features, ancestry, and genetics. Ethnic groups are based on cultural affiliations. Conceptions of race and ethnicity impact on social identity and hence identity politics. Race or ethnicity are related to concepts of kinship and descent.

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. [9] 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 hemophilia more often than women.

Intelligence

see below: Human#Consciousness

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 [10] 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 four species to pass the mirror test — which tests whether an animal recognizes 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 or joy, contrast with those perceived as unpleasant, like hate, envy, or jealousy.

In Pensées, Blaise Pascal wrote of the emotions:

Weariness — Nothing is so insufferable to man as to be completely at rest, without passions, without business, without diversion, without study. He then feels his nothingness, his forlornness, his insufficiency, his dependence, his weakness, his emptiness. There will immediately arise from the depth of his heart weariness, gloom, sadness, fretfulness, vexation, despair, (Pascal, 1669).

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 behavior. 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. Some cultures, groups and individuals insist on monogamy, while many others practice polygamy or forms of alternative sexuality. Acceptance of particular types of sexuality vary wildly 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 jewelry. Hairstyles and hair color 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 colonize 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 ionizing 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 out of 6.3 billion people live in urban centers, 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 some philosophers argue that free will is an illusion.

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 center 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

Template:Seemain2 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.

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Adi Shankara

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.

Psyche

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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 friend, 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, organizing self, whose job it is to satisfy the id but not upset the superego). [11] (See also Ego, Superego and Id.)

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

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. emphasizing 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".

From a scientific viewpoint, Homo sapiens certainly is among the most generalized species on Earth, and few single species occupy as many diverse environments as humans. Various attempts have been made to identify a single behavioral 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. 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

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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 artifacts. A culture's values define what it holds to be important. Norms are expectations of how people ought to behave. Artifacts – things, or material culture – derive from the culture's values and norms together with its understanding of the way the world functions.

Language

Template:Seemain2 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 [12] [13] (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.

Artifacts, technology and science

Template:Seemain4 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 artifacts 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 artifact, 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.

Animism is the belief that objects and ideas including animals, tools, and natural phenomena have or are expressions of living spirits. In hunter-gatherer cultures, the human being is often regarded as on a roughly equal footing with animals, plants, and natural forces. Ancestor worship by those surviving the deceased is often considered necessary for the successful completion of this journey.

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 the 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.

Hinduism also later developed monotheistic theologies such as monistic theism, which is different from Western notions of monotheism.

Humanism as a philosophy defines a socio-political doctrine the bounds of which are not constrained by those of locally developed cultures, but which includes all of humanity and all issues common to human beings. Because collective spirituality often manifests as religion, 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.

References

Taxonomy of living primates, Minnesota State University Mankato, retrieved April 4, 2005
Life expectancy in the U.S., 2001, National Center for Health Statistics, Centers for Disease Control and Prevention, December 8, 2004, retrieved April 2, 2005
U.N. Statistics on Population Ageing, United Nations press release, February 28, 2002, retrieved April 2, 2005
The World Factbook, U.S. Central Intelligence Agency, retrieved April 2, 2005
"Freud's Structural and Topographical Models of Personality", All-Psych online, retrieved April 2, 2005
"Conscious Awareness & The Unconscious Mind" by Rhawn Joseph, Brainmind.com, retrieved April 3, 2005
"Chimpanzee Communication: Insight into the Origin of Language" by Amy Stafford, Minnesota State University Mankato, retrieved April 4, 2005
Genetic migrations, by Kevin Duerinck, retrieved April 5, 2005
"Apes and Language: A Literature Review" (pdf) by Karen Shaw, Montana State University-Billings, retrieved April 19, 2005
"Divergence between samples of chimpanzee and human DNA sequences is 5%, counting indels" by R.J. Britten, California Institute of Technology, October 4, 2002
Boyd, Robert, and Joan B. Silk. 2003. How Humans Evolved. New York: Norton & Company. ISBN 0393978540.
Descartes, René. Discourse on Method and Meditations on First Philosophy. (Meditations first published 1641), Hackett Publishing Company, 1999, ISBN 0872204200
Dennett, Daniel. Consciousness Explained. Little Brown & Co, 1991, ISBN 0316180653
Harding, Rosalind M., Eugene Healy, Amanda J. Ray, Nichola S. Ellis, Niamh Flanagan, Carol Todd, Craig Dixon, Antti Sajantila, Ian J. Jackson, Mark A. Birch-Machin, and Jonathan L. Rees. 2000. "Evidence for variable selective pressures at MC1R." American Journal of Human Genetics 66: 1351-1361.
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