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Saturday, February 14, 2015

Pollution


From Wikipedia, the free encyclopedia


The litter problem on the coast of Guyana, 2010

Pollution is the introduction of contaminants into the natural environment that cause adverse change.[1] Pollution can take the form of chemical substances or energy, such as noise, heat or light. Pollutants, the components of pollution, can be either foreign substances/energies or naturally occurring contaminants. Pollution is often classed as point source or nonpoint source pollution.

Ancient cultures

Air pollution has always accompanied civilizations. Pollution started from prehistoric times when man created the first fires. According to a 1983 article in the journal Science, "soot found on ceilings of prehistoric caves provides ample evidence of the high levels of pollution that was associated with inadequate ventilation of open fires."[2] Metal forging appears to be a key turning point in the creation of significant air pollution levels outside the home. Core samples of glaciers in Greenland indicate increases in pollution associated with Greek, Roman and Chinese metal production,[3] but at that time the pollution was comparatively small and could be handled by nature.

Urban pollution


Air pollution in the US, 1973

The burning of coal and wood, and the presence of many horses in concentrated areas made the cities the cesspools of pollution. The Industrial Revolution brought an infusion of untreated chemicals and wastes into local streams that served as the water supply. King Edward I of England banned the burning of sea-coal by proclamation in London in 1272, after its smoke became a problem.[4][5] But the fuel was so common in England that this earliest of names for it was acquired because it could be carted away from some shores by the wheelbarrow.

Air pollution would continue to be a problem in England, especially later during the industrial revolution, and extending into the recent past with the Great Smog of 1952. London also recorded one of the earlier extreme cases of water quality problems with the Great Stink on the Thames of 1858, which led to construction of the London sewerage system soon afterward. Pollution issues escalated as population growth far exceeded view ability of neighborhoods to handle their waste problem. Reformers began to demand sewer systems, and clean water.[6]

It was the industrial revolution that gave birth to environmental pollution as we know it today. The emergence of great factories and consumption of immense quantities of coal gave rise to unprecedented air pollution and the large volume of industrial chemical discharges added to the growing load of untreated human waste. Chicago and Cincinnati were the first two American cities to enact laws ensuring cleaner air in 1881. Pollution became a major issue in the United States in the early twentieth century, as progressive reformers took issue with air pollution caused by coal burning, water pollution caused by bad sanitation, and street pollution caused by the 3 million horses who worked in American cities in 1900, generating large quantities of urine and manure. As historian Martin Melosi notes, The generation that first saw automobiles replacing the horses saw cars as "miracles of cleanliness.".[7] By the 1940s, however, automobile-caused smog was a major issue in Los Angeles.[8]

Other cities followed around the country until early in the 20th century, when the short lived Office of Air Pollution was created under the Department of the Interior. Extreme smog events were experienced by the cities of Los Angeles and Donora, Pennsylvania in the late 1940s, serving as another public reminder.[9]

In 1870, the sanitary conditions in Berlin were among the worst in Europe. August Bebel recalled conditions before a modern sewer system was built in the late 1870s:
"Waste-water from the houses collected in the gutters running alongside the curbs and emitted a truly fearsome smell. There were no public toilets in the streets or squares. Visitors, especially women, often became desperate when nature called. In the public buildings the sanitary facilities were unbelievably primitive....As a metropolis, Berlin did not emerge from a state of barbarism into civilization until after 1870."[10]
The primitive conditions were intolerable for a world national capital, and the Imperial German government brought in its scientists, engineers and urban planners to not only solve the deficiencies but to forge Berlin as the world's model city. A British expert in 1906 concluded that Berlin represented "the most complete application of science, order and method of public life," adding "it is a marvel of civic administration, the most modern and most perfectly organized city that there is."[11]
Awareness of atmospheric pollution spread widely after World War II, with fears triggered by reports of radioactive fallout from atomic warfare and testing.[12] Then a non-nuclear event, The Great Smog of 1952 in London, killed at least 4000 people.[13] This prompted some of the first major modern environmental legislation, The Clean Air Act of 1956.

Pollution began to draw major public attention in the United States between the mid-1950s and early 1970s, when Congress passed the Noise Control Act, the Clean Air Act, the Clean Water Act and the National Environmental Policy Act.[14]

Smog Pollution in Taiwan

Severe incidents of pollution helped increase consciousness. PCB dumping in the Hudson River resulted in a ban by the EPA on consumption of its fish in 1974. Long-term dioxin contamination at Love Canal starting in 1947 became a national news story in 1978 and led to the Superfund legislation of 1980.[15] The pollution of industrial land gave rise to the name brownfield, a term now common in city planning.

The development of nuclear science introduced radioactive contamination, which can remain lethally radioactive for hundreds of thousands of years. Lake Karachay, named by the Worldwatch Institute as the "most polluted spot" on earth, served as a disposal site for the Soviet Union throughout the 1950s and 1960s. Second place may go to the area of Chelyabinsk Russian as the "Most polluted place on the planet".[16]

Nuclear weapons continued to be tested in the Cold War, especially in the earlier stages of their development. The toll on the worst-affected populations and the growth since then in understanding about the critical threat to human health posed by radioactivity has also been a prohibitive complication associated with nuclear power. Though extreme care is practiced in that industry, the potential for disaster suggested by incidents such as those at Three Mile Island and Chernobyl pose a lingering specter of public mistrust. Worldwide publicity has been intense on those disasters.[17]
Widespread support for test ban treaties has ended almost all nuclear testing in the atmosphere.[18]
International catastrophes such as the wreck of the Amoco Cadiz oil tanker off the coast of Brittany in 1978 and the Bhopal disaster in 1984 have demonstrated the universality of such events and the scale on which efforts to address them needed to engage. The borderless nature of atmosphere and oceans inevitably resulted in the implication of pollution on a planetary level with the issue of global warming. Most recently the term persistent organic pollutant (POP) has come to describe a group of chemicals such as PBDEs and PFCs among others. Though their effects remain somewhat less well understood owing to a lack of experimental data, they have been detected in various ecological habitats far removed from industrial activity such as the Arctic, demonstrating diffusion and bioaccumulation after only a relatively brief period of widespread use.

A much more recently discovered problem is the Great Pacific Garbage Patch, a huge concentration of plastics, chemical sludge and other debris which has been collected into a large area of the Pacific Ocean by the North Pacific Gyre. This is a less well known pollution problem than the others described above, but nonetheless has multiple and serious consequences such as increasing wildlife mortality, the spread of invasive species and human ingestion of toxic chemicals. Organizations such as 5 Gyres have researched the pollution and, along with artists like Marina DeBris, are working toward publicizing the issue.

Growing evidence of local and global pollution and an increasingly informed public over time have given rise to environmentalism and the environmental movement, which generally seek to limit human impact on the environment.

Forms of pollution


The Lachine Canal in Montreal Canada, is polluted.

The major forms of pollution are listed below along with the particular contaminant relevant to each of them:

Pollutants

A pollutant is a waste material that pollutes air, water or soil. Three factors determine the severity of a pollutant: its chemical nature, the concentration and the persistence.

Sources and causes

Air pollution produced by ships may alter clouds, affecting global temperatures.

Air pollution comes from both natural and human-made (anthropogenic) sources. However, globally human-made pollutants from combustion, construction, mining, agriculture and warfare are increasingly significant in the air pollution equation.[20]

Motor vehicle emissions are one of the leading causes of air pollution.[21][22][23] China, United States, Russia, India[24] Mexico, and Japan are the world leaders in air pollution emissions. Principal stationary pollution sources include chemical plants, coal-fired power plants, oil refineries,[25] petrochemical plants, nuclear waste disposal activity, incinerators, large livestock farms (dairy cows, pigs, poultry, etc.), PVC factories, metals production factories, plastics factories, and other heavy industry. Agricultural air pollution comes from contemporary practices which include clear felling and burning of natural vegetation as well as spraying of pesticides and herbicides[26]

About 400 million metric tons of hazardous wastes are generated each year.[27] The United States alone produces about 250 million metric tons.[28] Americans constitute less than 5% of the world's population, but produce roughly 25% of the world’s CO
2
,[29] and generate approximately 30% of world’s waste.[30][31] In 2007, China has overtaken the United States as the world's biggest producer of CO
2
,[32] while still far behind based on per capita pollution - ranked 78th among the world's nations.[33]

An industrial area, with a power plant, south of Yangzhou's downtown, China

In February 2007, a report by the Intergovernmental Panel on Climate Change (IPCC), representing the work of 2,500 scientists, economists, and policymakers from more than 120 countries, said that humans have been the primary cause of global warming since 1950. Humans have ways to cut greenhouse gas emissions and avoid the consequences of global warming, a major climate report concluded. But to change the climate, the transition from fossil fuels like coal and oil needs to occur within decades, according to the final report this year from the UN's Intergovernmental Panel on Climate Change (IPCC).[34]

Some of the more common soil contaminants are chlorinated hydrocarbons (CFH), heavy metals (such as chromium, cadmium–found in rechargeable batteries, and lead–found in lead paint, aviation fuel and still in some countries, gasoline), MTBE, zinc, arsenic and benzene. In 2001 a series of press reports culminating in a book called Fateful Harvest unveiled a widespread practice of recycling industrial byproducts into fertilizer, resulting in the contamination of the soil with various metals. Ordinary municipal landfills are the source of many chemical substances entering the soil environment (and often groundwater), emanating from the wide variety of refuse accepted, especially substances illegally discarded there, or from pre-1970 landfills that may have been subject to little control in the U.S. or EU. There have also been some unusual releases of polychlorinated dibenzodioxins, commonly called dioxins for simplicity, such as TCDD.[35]

Pollution can also be the consequence of a natural disaster. For example, hurricanes often involve water contamination from sewage, and petrochemical spills from ruptured boats or automobiles. Larger scale and environmental damage is not uncommon when coastal oil rigs or refineries are involved. Some sources of pollution, such as nuclear power plants or oil tankers, can produce widespread and potentially hazardous releases when accidents occur.

In the case of noise pollution the dominant source class is the motor vehicle, producing about ninety percent of all unwanted noise worldwide.

Effects

Human health

Overview of main health effects on humans from some common types of pollution.[36][37][38]

Adverse air quality can kill many organisms including humans. Ozone pollution can cause respiratory disease, cardiovascular disease, throat inflammation, chest pain, and congestion. Water pollution causes approximately 14,000 deaths per day, mostly due to contamination of drinking water by untreated sewage in developing countries. An estimated 500 million Indians have no access to a proper toilet,[39][40] Over ten million people in India fell ill with waterborne illnesses in 2013, and 1,535 people died, most of them children.[41] Nearly 500 million Chinese lack access to safe drinking water.[42] A 2010 analysis estimated that 1.2 million people died prematurely each year in China because of air pollution.[43] The WHO estimated in 2007 that air pollution causes half a million deaths per year in India.[44] Studies have estimated that the number of people killed annually in the United States could be over 50,000.[45]

Oil spills can cause skin irritations and rashes. Noise pollution induces hearing loss, high blood pressure, stress, and sleep disturbance. Mercury has been linked to developmental deficits in children and neurologic symptoms. Older people are majorly exposed to diseases induced by air pollution. Those with heart or lung disorders are at additional risk. Children and infants are also at serious risk. Lead and other heavy metals have been shown to cause neurological problems. Chemical and radioactive substances can cause cancer and as well as birth defects.

Environment

Pollution has been found to be present widely in the environment. There are a number of effects of this:

Environmental health information

The Toxicology and Environmental Health Information Program (TEHIP)[46] at the United States National Library of Medicine (NLM) maintains a comprehensive toxicology and environmental health web site that includes access to resources produced by TEHIP and by other government agencies and organizations. This web site includes links to databases, bibliographies, tutorials, and other scientific and consumer-oriented resources. TEHIP also is responsible for the Toxicology Data Network (TOXNET)[47] an integrated system of toxicology and environmental health databases that are available free of charge on the web.

TOXMAP is a Geographic Information System (GIS) that is part of TOXNET. TOXMAP uses maps of the United States to help users visually explore data from the United States Environmental Protection Agency's (EPA) Toxics Release Inventory and Superfund Basic Research Programs.

Regulation and monitoring

To protect the environment from the adverse effects of pollution, many nations worldwide have enacted legislation to regulate various types of pollution as well as to mitigate the adverse effects of pollution.

Pollution control


A litter trap catches floating waste in the Yarra River, east-central Victoria, Australia

Gas nozzle with vapor recovery

A Mobile Pollution Check Vehicle in India.

Pollution control is a term used in environmental management. It means the control of emissions and effluents into air, water or soil. Without pollution control, the waste products from consumption, heating, agriculture, mining, manufacturing, transportation and other human activities, whether they accumulate or disperse, will degrade the environment. In the hierarchy of controls, pollution prevention and waste minimization are more desirable than pollution control. In the field of land development, low impact development is a similar technique for the prevention of urban runoff.

Practices

Pollution control devices

Perspectives

The earliest precursor of pollution generated by life forms would have been a natural function of their existence. The attendant consequences on viability and population levels fell within the sphere of natural selection. These would have included the demise of a population locally or ultimately, species extinction. Processes that were untenable would have resulted in a new balance brought about by changes and adaptations. At the extremes, for any form of life, consideration of pollution is superseded by that of survival.

For humankind, the factor of technology is a distinguishing and critical consideration, both as an enabler and an additional source of byproducts. Short of survival, human concerns include the range from quality of life to health hazards. Since science holds experimental demonstration to be definitive, modern treatment of toxicity or environmental harm involves defining a level at which an effect is observable. Common examples of fields where practical measurement is crucial include automobile emissions control, industrial exposure (e.g. Occupational Safety and Health Administration (OSHA) PELs), toxicology (e.g. LD50), and medicine (e.g. medication and radiation doses).

"The solution to pollution is dilution", is a dictum which summarizes a traditional approach to pollution management whereby sufficiently diluted pollution is not harmful.[49][50] It is well-suited to some other modern, locally scoped applications such as laboratory safety procedure and hazardous material release emergency management. But it assumes that the dilutant is in virtually unlimited supply for the application or that resulting dilutions are acceptable in all cases.

Such simple treatment for environmental pollution on a wider scale might have had greater merit in earlier centuries when physical survival was often the highest imperative, human population and densities were lower, technologies were simpler and their byproducts more benign. But these are often no longer the case. Furthermore, advances have enabled measurement of concentrations not possible before. The use of statistical methods in evaluating outcomes has given currency to the principle of probable harm in cases where assessment is warranted but resorting to deterministic models is impractical or infeasible. In addition, consideration of the environment beyond direct impact on human beings has gained prominence.

Yet in the absence of a superseding principle, this older approach predominates practices throughout the world. It is the basis by which to gauge concentrations of effluent for legal release, exceeding which penalties are assessed or restrictions applied. One such superseding principle is contained in modern hazardous waste laws in developed countries, as the process of diluting hazardous waste to make it non-hazardous is usually a regulated treatment process.[51] Migration from pollution dilution to elimination in many cases can be confronted by challenging economical and technological barriers.

Greenhouse gases and global warming

Historical and projected CO2 emissions by country.
Source: Energy Information Administration.[52][53]

Carbon dioxide, while vital for photosynthesis, is sometimes referred to as pollution, because raised levels of the gas in the atmosphere are affecting the Earth's climate. Disruption of the environment can also highlight the connection between areas of pollution that would normally be classified separately, such as those of water and air. Recent studies have investigated the potential for long-term rising levels of atmospheric carbon dioxide to cause slight but critical increases in the acidity of ocean waters, and the possible effects of this on marine ecosystems.

Most polluted places in the developing world

The Blacksmith Institute, an international non-for-profit organization dedicated to eliminating life-threatening pollution in the developing world, issues an annual list of some of the world's worst polluted places. In the 2007 issues the ten top nominees, already industrialized countries excluded, are located in Azerbaijan, China, India, Peru, Russia, Ukraine and Zambia.[54]

Chimpanzee


From Wikipedia, the free encyclopedia
Schimpanse Zoo Leipzig.jpg

Common chimpanzee (Pan troglodytes)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Hominidae
Subfamily: Homininae
Tribe: Panini
Genus: Pan
Oken, 1816
Type species
Pan troglodytes
Blumenbach, 1775
Species
Pan troglodytes
Pan paniscus
Pan.png
Distribution of Pan troglodytes (common chimpanzee) and Pan paniscus (bonobo, in red)
Synonyms
Troglodytes E. Geoffroy, 1812 (preoccupied)
Mimetes Leach, 1820 (preoccupied)
Theranthropus Brookes, 1828
Chimpansee Voight, 1831
Anthropopithecus Blainville, 1838
Hylanthropus Gloger, 1841
Pseudanthropus Reichenbach, 1862
Engeco Haeckel, 1866
Fsihego DePauw, 1905

Chimpanzees, sometimes colloquially chimps, are two extant hominid species of apes in the genus Pan. The Congo River divides the native habitats of the two species:[2]
Chimpanzees are members of the family Hominidae, along with humans, gorillas, and orangutans.
Chimpanzees split from the human branch of the family about four to six million years ago.
Chimpanzees are the closest living relatives to humans, being members of the tribe Hominini (along with extinct species of subtribe Hominina). Chimpanzees are the only known members of the subtribe Panina. The two Pan species split only about one million years ago.

Evolutionary history

Evolutionary relationship

The genus Pan is part of the subfamily Homininae, to which humans also belong. These two species are the closest living evolutionary relatives to humans, sharing a common ancestor with humans about four to six million years ago.[3] Research by Mary-Claire King in 1973 found 99% identical DNA between human beings and chimpanzees,[4] although research since has modified that finding to about 94%[5] commonality, with some of the difference occurring in noncoding DNA. P. troglodytes and P. paniscus have been proposed to belong with H. sapiens in the genus Homo, rather than in Pan; e.g., by J. Diamond in his book, wherein he refers to man as The Third Chimpanzee. Among the arguments in favor of this reclassification is that other species have been reclassified to belong to the same genus because of less genetic similarity than that between humans and chimpanzees.
Taxonomy of genus Pan[1] Phylogeny of superfamily Hominoidea[6](Fig. 4)
 Hominoidea




 humans (genus Homo)


 chimpanzees (genus Pan)



 gorillas (genus Gorilla)



 orangutans (genus Pongo)



 gibbons (family Hylobatidae)


Fossils

Though many human fossils have been found, chimpanzee fossils were not described until 2005. Existing chimpanzee populations in West and Central Africa are separate from the major human fossil sites in East Africa; however, chimpanzee fossils have been reported from Kenya, indicating that both humans and members of the Pan clade were present in the East African Rift Valley during the Middle Pleistocene.[7]
(video) Female Chimpanzee at Tobu Zoo in Saitama, Japan.

Anatomy and physiology


Human and chimp skulls and brains (not to scale), as illustrated in Gervais' Histoire naturelle des mammifères

The chimpanzee's brain on the left and the man's brain on the right have been scaled to the same size to show the relative proportions of their parts. These drawings were in a book made in 1904 by Thomas Henry Huxley.[8]

The male common chimp stands up to 1.7 m (5.6 ft) high and weighs as much as 70 kg (150 lb); the female is somewhat smaller. The common chimp’s long arms, when extended, span one and a half times the body’s height. A chimpanzee's arms are longer than its legs.[9] The bonobo is slightly shorter and thinner than the common chimpanzee but has longer limbs. In trees, both species climb with their long, powerful arms; on the ground, chimpanzees usually knuckle-walk, or walk on all fours, clenching their fists and supporting themselves on the knuckles thereof. Chimpanzee feet are better suited for walking than are those of the orangutan because the chimp has broader soles and shorter toes.

Both the common chimpanzee and bonobo can walk upright on two legs when carrying objects with their hands and arms. The bonobo has proportionately longer upper limbs and more often walks upright than does the common chimpanzee. The coat is dark; the face, fingers, palms of the hands, and soles of the feet, hairless; the chimp, tailless. The exposed skin of the face, hands and feet varies from pink to very dark in both species but is generally lighter in younger individuals, darkening as maturity is reached. A University of Chicago Medical Centre study has found significant genetic differences between chimpanzee populations.[10] A bony shelf over the eyes gives the forehead a receding appearance, and the nose is flat. Although the jaws protrude, the lips are thrust out only when a chimp pouts.

The brain of a chimpanzee has been measured at ~337 cc,[11][12] ~393 cc,[13] with a general range of 282–500 cc.[14] Human brains, in contrast, have been measured as being three times larger, variously reported volumes include ~1,299 cc,[11][12] ~1,158 cc,[13] and averages of ~1330 cc.[15][16][17][18][19][20][21][22]

Chimpanzee testicles are unusually large for their body size, with a combined weight of about 4 oz (110 g) compared to a gorilla's 1 oz (28 g) or a human's 1.5 ounces (43 g). This relatively great size is generally attributed to sperm competition due to the polyandrous nature of chimpanzee mating behavior.[23] Chimpanzees reach puberty between the age of eight and ten years[citation needed] and one study estimates that they live an average of 35 years (33 years for males, and 37 years for females) in the wild,[24] but some have lived longer than 60 years in captivity.[citation needed]

Behavior


Bonobo

Anatomical differences between the common chimpanzee and the bonobo are slight, but sexual and social behaviors are markedly different. The common chimpanzee has an omnivorous diet, a troop hunting culture based on beta males led by an alpha male, and highly complex social relationships. The bonobo, on the other hand, has a mostly frugivorous diet and an egalitarian, nonviolent, matriarchal, sexually receptive behavior.[25] Bonobos frequently have sex, sometimes to help prevent and resolve conflicts. Different groups of chimpanzees also have different cultural behavior with preferences for types of tools.[26] The common chimpanzee tends to display greater aggression than does the bonobo.[27] The average, captive chimpanzee sleeps 9.7 hours per day.[28]

Social structure


Common chimpanzees in Gombe Stream National Park

Chimpanzees live in large multi-male and multi-female social groups, which are called communities. Within a community, the position of an individual and the influence the individual has on others dictates a definite social hierarchy. Chimpanzees live in a leaner hierarchy wherein more than one individual may be dominant enough to dominate other members of lower rank. Typically, a dominant male is referred to as the alpha male. The alpha male is the highest-ranking male that controls the group and maintains order during disputes. In chimpanzee society, the 'dominant male' sometimes is not the largest or strongest male but rather the most manipulative and political male that can influence the goings on within a group. Male chimpanzees typically attain dominance by cultivating allies who will support that individual during future ambitions for power. The alpha male regularly displays by puffing his normally slim coat up to increase view size and charge to seem as threatening and as powerful as possible; this behavior serves to intimidate other members and thereby maintain power and authority, and it may be fundamental to the alpha male's holding on to his status. Lower-ranking chimpanzees will show respect by submissively gesturing in body language or reaching out their hands while grunting. Female chimpanzees will show deference to the alpha male by presenting their hindquarters.

Female chimpanzees also have a hierarchy, which is influenced by the position of a female individual within a group. In some chimpanzee communities, the young females may inherit high status from a high-ranking mother. Dominant females will also ally to dominate lower-ranking females: whereas males mainly seek dominant status for its associated mating privileges and sometimes violent domination of subordinates, females seek dominant status to acquire such resources as food. High-ranking females often have first access. Both genders acquire dominant status to improve social standing within a group.

Community female acceptance is necessary for alpha male status; females must ensure that their group visits places that supply them with enough food. A group of dominant females will sometimes oust an alpha male which is not to their preference and back another male, in whom they see potential for leading the group as a successful alpha male.

Intelligence

Diagram of brain – topography of the main groups of foci in the motor field of chimpanzee

Chimpanzees make tools and use them to acquire foods and for social displays; they have sophisticated hunting strategies requiring cooperation, influence and rank; they are status conscious, manipulative and capable of deception; they can learn to use symbols and understand aspects of human language including some relational syntax, concepts of number and numerical sequence;[29] and they are capable of spontaneous planning for a future state or event.[30]

Tool use


Common chimpanzee using a stick

In October 1960, Jane Goodall observed the use of tools among chimpanzees. Recent research indicates chimpanzee stone tool use dates to at least 4,300 years ago.[31] Chimpanzee tool usage includes digging into termite mounds with a large stick tool, and then using a small stick that has been altered to "fish" the termites out.[32] There have been occasional unsubstantiated or controversial reports of Chimpanzees using rocks or sticks as weapons.[33] A recent study claimed to reveal the use of spears, which common chimpanzees in Senegal sharpen with their teeth and use to stab and pry Senegal bushbabies out of small holes in trees.[34][35] Chimpanzees are also known to use stones as anvils and hammers in order to break open nuts.[36] Before the discovery of tool use in chimps, humans were believed to be the only species to make and use tools, but several other tool-using species are now known.[37][38]

Nest-building

Nest-building, sometimes considered as tool use, is seen in chimpanzees which construct arboreal night nests by lacing together branches from one or more trees. It forms an important part of behavior, especially in the case of mothers who teach this trait to infants. Nests consist of a mattress, supported on a strong foundation, and lined above with soft leaves and twigs, and are built in trees with a minimum diameter of 5 metres (16 ft) and may be located at a height of 3 to 45 metres (9.8 to 147.6 ft). Both day and night nests are built; they may be located in groups.[39] A study in 2014 found that the Muhimbi tree is favoured for nest building by chimpanzees in Uganda due to its physical properties, such as bending strength, inter-node distance, and leaf surface area.[40]

Altruism and emotivity


Chimpanzee mother and baby

Studies have shown chimpanzees engage in apparently altruistic behavior within groups.[41][42] Some researchers have said chimpanzees are indifferent to the welfare of unrelated group members,[43] but a more recent study of wild chimpanzees found that both male and female adults would adopt orphaned young of their group. Also, different groups sometimes share food, form coalitions, and cooperate in hunting and border patrolling.[44] Sometimes chimpanzees have adopted young that come from unrelated groups. And in some rare cases, even male chimps have been shown to take care of abandoned infant chimps of an unrelated group, though in most cases they would kill the infant.[citation needed]

According to James W. Harrod, evidence for chimpanzee emotivity includes display of mourning, "incipient romantic love", rain dances, appreciation of natural beauty such as a sunset over a lake, curiosity and respect towards wildlife (such as the python, which is neither a threat nor a food source to chimpanzees), altruism toward other species (such as feeding turtles) and animism, or "pretend play", in chimps cradling and grooming rocks or sticks.[45]

Communication

Chimps communicate in a manner similar to human nonverbal communication, using vocalizations, hand gestures, and facial expressions. Research into the chimpanzee brain has revealed chimp communication activates an area of the chimp brain in the same position as Broca's area, a language center in the human brain.[46]

There is some debate as to whether chimpanzees have the ability to express hierarchical ideas in language. Studies have found that chimps are capable of learning a limited set of sign language symbols, which they can use to communicate with human trainers. However, it is clear that there are distinct limits to the complexity of knowledge structures with which chimps are capable of dealing. The sentences that they can express are limited to specific simple noun-verb sequences and are not capable of the indefinite expansion of complexity characteristic of humans.

Aggression

Adult common chimpanzees, particularly males, can be very aggressive. They are highly territorial and are known to kill other chimps.[47]

Common chimpanzee with hunted bushbuck on a tree in Gombe Stream National Park

Hunting

Chimpanzees also engage in targeted hunting of lower-order primates such as the red colobus[48] and bush babies,[49][50] and use the meat from these kills as a "social tool" within their community.[51]

Puzzle solving

In February 2013, a study found chimpanzees solve puzzles for entertainment.[52]

Interactions with humans

History

62-year-old chimpanzee
Gregoire: 62-year-old chimpanzee

Africans have had contact with chimpanzees for millennia. Chimpanzees have been kept as pets for centuries in a few African villages, especially in the Democratic Republic of Congo. In Virunga National Park in the east of the country, the park authorities regularly confiscate chimpanzees from people keeping them as pets.[53] The first recorded contact of Europeans with chimps took place in present-day Angola during the 17th century. The diary of Portuguese explorer Duarte Pacheco Pereira (1506), preserved in the Portuguese National Archive (Torre do Tombo), is probably the first European document to acknowledge chimpanzees built their own rudimentary tools.

The first use of the name "chimpanzee", however, did not occur until 1738. The name is derived from a Tshiluba language term kivili-chimpenze, which is the local name for the animal and translates loosely as "mockman" or possibly just "ape". The colloquialism "chimp" was most likely coined some time in the late 1870s.[54] Biologists applied Pan as the genus name of the animal. Chimps, as well as other apes, had also been purported to have been known to Western writers in ancient times, but mainly as myths and legends on the edge of European and Arab societal consciousness, mainly through fragmented and sketchy accounts of European adventurers. Apes are mentioned variously by Aristotle, as well as the English Bible, where they are described as having been collected by Solomon. (1 Kings 10:22. However the Hebrew word, qőf, may mean a monkey.) Apes are mentioned in the Qur'an (7:166), where God tells Israelites who transgressed Shabbat "Be ye apes". The first of these early transcontinental chimpanzees came from Angola and were presented as a gift to Frederick Henry, Prince of Orange in 1640, and were followed by a few of its brethren over the next several years. Scientists described these first chimpanzees as "pygmies", and noted the animals' distinct similarities to humans. The next two decades, a number of the creatures were imported into Europe, mainly acquired by various zoological gardens as entertainment for visitors.

Hugo Rheinhold's Affe mit Schädel ("Ape with skull") is an example of how chimps were viewed at the end of the 19th century.

Darwin's theory of natural selection (published in 1859) spurred scientific interest in chimpanzees, as in much of life science, leading eventually to numerous studies of the animals in the wild and captivity. The observers of chimpanzees at the time were mainly interested in behavior as it related to that of humans. This was less strictly and disinterestedly scientific than it might sound, with much attention being focused on whether or not the animals had traits that could be considered 'good'; the intelligence of chimpanzees was often significantly exaggerated, as immortalized in Hugo Rheinhold's Affe mit Schädel (see image, left). By the end of the 19th century, chimpanzees remained very much a mystery to humans, with very little factual scientific information available.

In the 20th century, a new age of scientific research into chimpanzee behavior began. Before 1960, almost nothing was known about chimpanzee behavior in their natural habitats. In July of that year, Jane Goodall set out to Tanzania's Gombe forest to live among the chimpanzees, where she primarily studied the members of the Kasakela chimpanzee community. Her discovery that chimpanzees made and used tools was groundbreaking, as humans were previously believed to be the only species to do so. The most progressive early studies on chimpanzees were spearheaded primarily by Wolfgang Köhler and Robert Yerkes, both of whom were renowned psychologists. Both men and their colleagues established laboratory studies of chimpanzees focused specifically on learning about the intellectual abilities of chimpanzees, particularly problem-solving. This typically involved basic, practical tests on laboratory chimpanzees, which required a fairly high intellectual capacity (such as how to solve the problem of acquiring an out-of-reach banana). Notably, Yerkes also made extensive observations of chimpanzees in the wild which added tremendously to the scientific understanding of chimpanzees and their behavior. Yerkes studied chimpanzees until World War II, while Köhler concluded five years of study and published his famous Mentality of Apes in 1925 (which is coincidentally when Yerkes began his analyses), eventually concluding, "chimpanzees manifest intelligent behaviour of the general kind familiar in human beings ... a type of behaviour which counts as specifically human" (1925).[55]

Chimpanzee at the Los Angeles Zoo

The August 2008 issue of the American Journal of Primatology reported results of a year-long study of chimpanzees in Tanzania’s Mahale Mountains National Park, which produced evidence of chimpanzees becoming sick from viral infectious diseases they have likely contracted from humans. Molecular, microscopic and epidemiological investigations demonstrated the chimpanzees living at Mahale Mountains National Park have been suffering from a respiratory disease that is likely caused by a variant of a human paramyxovirus.[56]

Animal research

As of November 2007, about 1,300 chimpanzees were housed in 10 U.S. laboratories (out of 3,000 great apes living in captivity there), either wild-caught, or acquired from circuses, animal trainers, or zoos.[57] Most of the labs either conduct or make the chimps available for invasive research,[58] defined as "inoculation with an infectious agent, surgery or biopsy conducted for the sake of research and not for the sake of the chimpanzee, and/or drug testing".[59] Two federally funded laboratories use chimps: the Yerkes National Primate Research Center at Emory University in Atlanta, Georgia, and the Southwest National Primate Center in San Antonio, Texas.[60] Five hundred chimps have been retired from laboratory use in the U.S. and live in animal sanctuaries in the U.S. or Canada.[58]

Ham the Astrochimp before being inserted into the Mercury-Redstone 2 capsule in 1961

Chimpanzees used in biomedical research tend to be used repeatedly over decades, rather than used and killed as with most laboratory animals. Some individual chimps currently in U.S. laboratories have been used in experiments for over 40 years.[61] According to Project R&R, a campaign to release chimps held in U.S. labs—run by the New England Anti-Vivisection Society in conjunction with Jane Goodall and other primate researchers—the oldest known chimp in a U.S. lab is Wenka, which was born in a laboratory in Florida on May 21, 1954.[62] She was removed from her mother on the day of birth to be used in a vision experiment that lasted 17 months, then sold as a pet to a family in North Carolina. She was returned to the Yerkes National Primate Research Center in 1957 when she became too big to handle. Since then, she has given birth six times, and has been the subject of research into alcohol use, oral contraceptives, aging, and cognitive studies.[63]

With the publication of the chimpanzee genome, plans to increase the use of chimps in labs are reportedly increasing, with some scientists arguing the federal moratorium on breeding chimps for research should be lifted.[60][64] A five-year moratorium was imposed by the U.S. National Institutes of Health in 1996, because too many chimps had been bred for HIV research, and it has been extended annually since 2001.[60]

Other researchers argue chimps are unique animals and either should not be used in research, or should be treated differently. Pascal Gagneux, an evolutionary biologist and primate expert at the University of California, San Diego, argues, given chimpanzees' sense of self, tool use, and genetic similarity to human beings, studies using chimps should follow the ethical guidelines used for human subjects unable to give consent.[60] Also, a recent study suggests chimpanzees which are retired from labs exhibit a form of posttraumatic stress disorder.[65] Stuart Zola, director of the Yerkes National Primate Research Laboratory, disagrees. He told National Geographic: "I don't think we should make a distinction between our obligation to treat humanely any species, whether it's a rat or a monkey or a chimpanzee. No matter how much we may wish it, chimps are not human."[60]

An increasing number of governments are enacting a great ape research ban forbidding the use of chimpanzees and other great apes in research or toxicology testing.[66] As of 2006, Austria, New Zealand, the Netherlands, Sweden, and the UK had introduced such bans.[67]

Studies of language

Side profile of a chimpanzee

Scientists have long been fascinated with the studies of language, believing it to be a unique human cognitive ability. To test this hypothesis, scientists have attempted to teach human language to several species of great apes. One early attempt by Allen and Beatrix Gardner in the 1960s involved spending 51 months teaching American Sign Language (ASL) to a chimpanzee named Washoe. The Gardners reported Washoe learned 151 signs, and she had spontaneously taught them to other chimpanzees.[68] Over a longer period of time, Washoe learned over 800 signs.[69]

Debate is ongoing among some scientists (such as David Premack), about nonhuman great apes' ability to learn language. Since the early reports on Washoe, numerous other studies have been conducted, with varying levels of success,[70] including one involving a chimpanzee named, in parody, Nim Chimpsky, trained by Herbert Terrace of Columbia University. Although his initial reports were quite positive, in November 1979, Terrace and his team (including psycholinguist Thomas Bever) re-evaluated the videotapes of Nim with his trainers, analyzing them frame by frame for signs, as well as for exact context (what was happening both before and after Nim’s signs). In the reanalysis, Terrace and Bever concluded Nim's utterances could be explained merely as prompting on the part of the experimenters, as well as mistakes in reporting the data. "Much of the apes’ behavior is pure drill," he said. "Language still stands as an important definition of the human species." In this reversal, Terrace now argued Nim's use of ASL was not like human language acquisition. Nim never initiated conversations himself, rarely introduced new words, and simply imitated what the humans did. More importantly, Nim's word strings varied in their ordering, suggesting that he was incapable of syntax. Nim’s sentences also did not grow in length, unlike human children whose vocabulary and sentence length show a strong positive correlation.[71]

Memory

A 30-year study at Kyoto University’s Primate Research Institute has shown chimps are able to learn to recognize the numbers 1 through 9 and their values. The chimps further show an aptitude for photographic memory, demonstrated in experiments in which the jumbled digits are flashed onto a computer screen for less than a quarter of a second, after which the chimp, Ayumu, is able to correctly and quickly point to the positions where they appeared in ascending order. The same experiment was failed by human world memory champion Ben Pridmore on most attempts.[72]

Laughter in apes

Young chimpanzees
Young chimpanzees playing

Laughter might not be confined or unique to humans. The differences between chimpanzee and human laughter may be the result of adaptations that have evolved to enable human speech.
Self-awareness of one's situation as seen in the mirror test, or the ability to identify with another's predicament (see mirror neurons), are prerequisites for laughter,[citation needed] so animals may be laughing in the same way as humans do.

Chimpanzees, gorillas, and orangutans show laughter-like vocalizations in response to physical contact, such as wrestling, play-chasing, or tickling. This is documented in wild and captive chimpanzees. Common chimpanzee laughter is not readily recognizable to humans as such, because it is generated by alternating inhalations and exhalations that sound more like breathing and panting. Instances in which nonhuman primates have expressed joy have been reported. One study analyzed and recorded sounds made by human babies and bonobos when tickled. Although the bonobo's laugh was a higher frequency, the laugh followed a pattern similar to that of human babies and included similar facial expressions. Humans and chimpanzees share similar ticklish areas of the body, such as the armpits and belly. The enjoyment of tickling in chimpanzees does not diminish with age.[73]

As pets

Chimpanzees are popular as wild pets in many areas despite their strength, aggression, and wild nature. Even in areas where keeping non-human primates as pets are illegal, the exotic pet trade continues to prosper and some people keep chimpanzees as pets mistakenly believing that they will bond with them for life. As they grow, so do their strength and aggression; some owners and others interacting with the animals have lost fingers and suffered severe facial damage among other injuries sustained in attacks. In addition to the animals' hostile potential and strength well beyond any human being, chimpanzees physically mature a lot more proportionally than do human beings, and even among the most cleanly and well-organized of housekeepers, maintaining cleanliness and control of chimpanzees is physically demanding to the point that it is impossible for humans to control, especially due to the animals' strength and aggression.[74]

In popular culture

Chimpanzees have been commonly stereotyped in popular culture, where they are most often cast in standardized roles as childlike companions, sidekicks or clowns.[75] They are especially suited for the latter role on account of their prominent facial features, long limbs and fast movements, which humans often find amusing. Accordingly, entertainment acts featuring chimpanzees dressed up as humans have been traditional staples of circuses and stage shows.[75]
In the age of television, a new genre of chimp act emerged in the United States: series whose cast consisted entirely of chimpanzees dressed as humans and "speaking" lines dubbed by human actors.[75] These shows, examples of which include Lancelot Link, Secret Chimp in the 1970s or The Chimp Channel in the 1990s, relied on the novelty of their ape cast to make their timeworn, low comedy gags funny.[75] Their chimpanzee "actors" were as interchangeable as the apes in a circus act, being amusing as chimpanzees and not as individuals.[75] Animal rights groups have urged a stop to this practice, considering it animal abuse.[76]

When chimpanzees appear in other TV shows, they generally do so as comic relief sidekicks to humans. In that role, for instance, J. Fred Muggs appeared with Today Show host Dave Garroway in the 1950s, Judy on Daktari in the 1960s or Darwin on The Wild Thornberrys in the 1990s.[75] In contrast to the fictional depictions of other animals, such as dogs (as in Lassie), dolphins (Flipper), horses (The Black Stallion) or even other great apes (King Kong), chimpanzee characters and actions are rarely relevant to the plot.[75]

Portrayals in science fiction

The rare depictions of chimpanzees as individuals rather than stock characters, and as central rather than incidental to the plot[75] are generally found in works of science fiction. Robert A. Heinlein's short story "Jerry Was a Man" (1947) centers on a genetically enhanced chimpanzee suing for better treatment. The 1972 film Conquest of the Planet of the Apes, the third sequel of Planet of the Apes, portrays a futuristic revolt of enslaved apes led by the only talking chimpanzee, Caesar, against their human masters.[75] This concept was revisited in the 2011 film Rise of the Planet of the Apes, again with a chimpanzee protagonist named Caesar. Another short story, "The Pope of the Chimps" by Robert Silverberg, set in the present day, shows the development of the first signs of religiosity in a group of chimpanzees, much to the surprise of the humans observing them. David Brin's Uplift novels present a future in which humans have "uplifted" chimpanzees (and certain other species) with human-level sapience.

Bayesian inference

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Bayesian_inference Bayesian inference ( / ...