Human Evolution

The scientific study of human evolution encompasses the development of the genus Homo, but usually involves studying other hominids and hominines as well, such as Australopithecus. "Modern humans" are defined as the Homo sapiens species, of which the only extant subspecies is Homo sapiens sapiens; Homo sapiens idaltu (roughly translated as "elder wise human"), the other known subspecies, is extinct.[5] Anatomically modern humans appear in the fossil record in Africa about 130,000 years ago.[6][7]
The closest living relatives of Homo sapiens are two distinct species of the genus Pan: the Bonobo (Pan paniscus) and the Common Chimpanzee (Pan troglodytes). These species share the same common ancestor. The main difference between them is the social organization: matriarchal for the Bonobo and patriarchal for the Common Chimpanzee. Full genome sequencing resulted in the conclusion that "after 6.5 million years of separate evolution, the differences between bonobo/chimpanzee and human are just 10 times greater than those between two unrelated people and 10 times less than those between rats and mice". In fact, 95 per cent of the DNA sequence is identical between the two Pan species and human.[8][9][10][11] 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, a hominid skull discovered in Chad in 2001, classified as Sahelanthropus tchadensis, is approximately seven million years old, which may indicate an earlier divergence.[12]
There are two prominent scientific theories of the origins of contemporary humans. They concern the relationship between modern humans and other hominids. The single-origin, or "out-of-Africa", hypothesis proposes that modern humans evolved in Africa and later migrated outwards to replace hominids in other parts of the world. The multiregional hypothesis, on the other hand, proposes that modern humans evolved, at least in part, from independent hominid populations.[13]
Geneticists Lynn Jorde and Henry Harpending of the University of Utah proposed that the variation in human DNA is minute compared to that of other species. They also propose that during the Late Pleistocene, the human population was reduced to a small number of breeding pairs — no more than 10,000 and possibly as few as 1,000 — resulting in a very small residual gene pool. Various reasons for this hypothetical bottleneck have been postulated, one of those is the Toba catastrophe theory.
Human evolution is characterized by a number of important morphological, developmental, physiological and behavioral changes which have taken place since the split between the last common ancestor of Homo and Pan. The primary change, both in terms of chronology and in terms of it being the trait that defines the human subtribe the Hominina, was the evolution of a bipedal locomotor adaptation from an arboreal or semi-arboreal locomotor adaptation, with all its attendant adaptations, such as a valgus knee, low intermembral index (long legs relative to the arms) and reduced upper body strength.[citation needed] Following this was the evolution of a larger brain cavity and brain itself, which is typically 1,400 cm³ in modern humans; over twice that of a chimpanzee or gorilla. Other significant morphological changes included: the evolution of a power and precision grip;[citation needed] a reduced masticatory system; a reduction of the canine tooth; and the descent of the larynx and hyoid bone, making speech possible. With respect to development, the pattern of human postnatal brain growth differs from that of other apes (heterochrony), allowing for an extended period of social learning and language acquisition in juvenile humans. Physical anthropologists argue that a reorganization of the structure of the brain is more important than cranial expansion itself. One important physiological change in humans was the evolution of hidden estrus or concealed ovulation in females, which may have coincided with the evolution of important behavioral changes, such as pair bonding. Another significant behavioral change includes the development of material culture, or the (over time) increasingly wide variety of human-made objects which are used to manipulate humans' physical and social environments. How all these changes are related and what their role is in the evolution of complex social organization and culture are matters of ongoing debate.[14][15]

Soil

Soil is defined as the top layer of the earth’s crust. It is formed by mineral particles, organic matter, water, air and living organisms. It is in fact an extremely complex, variable and living medium. The interface between the earth, the air and the water, soil is a non-renewable resource which performs many vital functions: food and other biomass production, storage, filtration and transformation of many substances including water, carbon, nitrogen. Soil has a role as a habitat and gene pool, serves as a platform for human activities, landscape and heritage and acts as a provider of raw materials. These functions are worthy of protection because of their socio-economic as well as environmental importance.
Erosion, loss of organic matter, compaction, salinisation, landslides, contamination, sealing… Soil degradation is accelerating, with negative effects on human health, natural ecosystems and climate change, as well as on our economy. At the moment, only nine EU Member States have specific legislation on soil protection (especially on contamination).
Different EU policies (for instance on water, waste, chemicals, industrial pollution prevention, nature protection, pesticides, agriculture) are contributing to soil protection. But as these policies have other aims and other scopes of action, they are not sufficient to ensure an adequate level of protection for all soil in Europe.
For all these reasons, in September 2006, the Commission adopted a comprehensive EU strategy specifically dedicated to soil protection.
The strategy is one of seven Thematic Strategies that the Commission has presented. The other strategies cover air pollution, the marine environment, waste prevention and recycling, natural resources, the urban environment and pesticides

Air

A clean air supply is essential to our own health and that of the environment. But since the industrial revolution, the quality of the air we breathe has deteriorated considerably - mainly as a result of human activities. Rising industrial and energy production, the burning of fossil fuels and the dramatic rise in traffic on our roads all contribute to air pollution in our towns and cities which, in turn, can lead to serious health problems. For example, air pollution is increasingly being cited as the main cause of lung conditions such as asthma - twice as many people suffer from asthma today compared to 20 years ago.
The issue of air quality is now a major concern for many European citizens. It is also one of the areas in which the European Union has been most active. Since the early 1970s, the EU has been working to improve air quality by controlling emissions of harmful substances into the atmosphere, improving fuel quality, and by integrating environmental protection requirements into the transport and energy sectors.
As the result of EU legislation, much progress has been made in tackling air pollutants such as sulphur dioxide, lead, nitrogen oxides, carbon monoxide and benzene. However, despite a reduction in some harmful emissions, air quality continues to cause problems. Summer smog - originating in potentially harmful ground-level ozone - regularly exceeds safe limits. Fine particulates also present a health risk which is of increasing concern. Clearly, more needs to be done at local, national, European and international level.
The EU's Sixth Environment Action Programme (EAP), "Environment 2010: Our future, Our choice", includes Environment and Health as one of the four main target areas requiring greater effort - and air pollution is one of the issues highlighted in this area. The Sixth EAP aims to achieve levels of air quality that do not result in unacceptable impacts on, and risks to, human health and the environment.
The EU is acting at many levels to reduce exposure to air pollution: through EC legislation, through work at international level to reduce cross-border pollution, through co-operation with sectors responsible for air pollution, through national, regional authorities and NGOs, and through research. The Clean Air For Europe (CAFE) initiative has led to a thematic strategy setting out the objectives and measures for the next phase of European air quality policy.

Climate Change

Climate change is one of the greatest environmental, social and economic threats facing the planet.
The warming of the climate system is unequivocal, as is now evident from observations of increases in global average air and ocean temperatures, widespread melting of snow and ice, and rising global mean sea level. The Earth's average surface temperature has risen by 0.76° C since 1850. Most of the warming that has occurred over the last 50 years is very likely to have been caused by human activities. In its Fourth Assessment Report (AR4), published on 2 February 2007, the Intergovernmental Panel on Climate Change (IPCC) projects that, without further action to reduce greenhouse gas emissions, the global average surface temperature is likely to rise by a further 1.8-4.0°C this century. Even the lower end of this range would take the temperature increase since pre-industrial times above 2°C, the threshold beyond which irreversible and possibly catastrophic changes become far more likely.
Projected global warming this century is likely to trigger serious consequences for humanity and other life forms, including a rise in sea levels of between 18 and 59 cm which will endanger coastal areas and small islands, and a greater frequency and severity of extreme weather events.
Q&A on Climate Change: 1 What makes the climate change? 2 How is climate changing and how has it changed in the past? 3 How is the climate going to change in the future? 4 What impacts of climate change have already been observed? 5 What impacts are expected in the future? 6 How do people adapt to climate change? 7 What are the current trends in greenhouse gas emissions? 8 What actions can be taken to reduce greenhouse gas emissions? 9 How can governments create incentives for mitigation? 10 Conclusion Provided by GreenFacts Human activities that contribute to climate change include in particular the burning of fossil fuels, agriculture and land-use changes like deforestation. These cause emissions of carbon dioxide (CO2), the main gas responsible for climate change, as well as of other 'greenhouse' gases. To bring climate change to a halt, global greenhouse gas emissions must be reduced significantly.
The European Union is at the forefront of international efforts to combat climate change and has played a key role in the development of the two major treaties addressing the issue, the 1992 United Nations Framework Convention on Climate Change and its Kyoto Protocol, agreed in 1997.
The EU has been taking serious steps to address its own greenhouse gas emissions since the early 1990s. In March 2000 the Commission launched the European Climate Change Programme (ECCP). The ECCP has led to the adoption of a wide range of new policies and measures. Among these is the pioneering EU Emissions Trading Scheme, launched on 1 January 2005, which has become the cornerstone of EU efforts to reduce emissions cost-effectively.
Monitoring data and projections indicate that the 15 European Union members at the time of the EU's ratification of the Kyoto Protocol in 2002 (EU-15) will reach their Kyoto Protocol target for cutting greenhouse gas emissions. This requires emissions in 2008-2012 to be 8% below 1990 levels.
However, Kyoto is only a first step. Ambitious action to reduce global emissions is needed after 2012, when Kyoto's targets expire, in order to limit global warming to 2°C. In January 2007 the European Commission set out proposals and options for achieving this in its Communication "Limiting Global Climate Change to 2 degrees Celsius: The way ahead for 2020 and beyond" The key targets in the Communication, as well as the broad thrust of the integrated energy and climate change strategy of which it forms part, were endorsed by EU leaders at their summit in Brussels on 8-9 March 2007.

The IPCC's latest scientific assessment "Climate Change 2007" can be downloaded here. Working Group I of the Intergovernmental Panel on Climate Change (IPCC) finalised the Summary for Policymakers of the first volume of “Climate Change 2007”, also known as the Fourth Assessment Report (AR4). The report “Climate Change 2007: The Physical Science Basis”, assesses the current scientific knowledge of the natural and human drivers of climate change, observed changes in climate, the ability of science to attribute changes to different causes, and projections for future climate change.

Natural environment

The natural environment, commonly referred to simply as the environment, is a term that comprises all living and non-living things that occur naturally on Earth or some part of it (e.g. the natural environment in a country). This term includes a few key components:
Complete landscape units that function as natural systems without massive human intervention, including all plants, animals, rocks, etc. and natural phenomena that occur within their boundaries. Universal natural resources and physical phenomena that lack clear-cut boundaries, such as air, water, and climate, as well as energy, radiation, electric charge, and magnetism, not originating from human activity. The natural environment is contrasted with the built environment, which comprises the areas and components that are heavily influenced by man. A geographical area is regarded as a natural environment (with an indefinite article), if the human impact on it is kept under a certain limited level (similar to section 1 above). This level depends on the specific context, and changes in different areas and contexts. The term wilderness, on the other hand, refers to areas without any human intervention whatsoever (or almost so).
[edit] ChallengesIt is the common understanding of natural environment that underlies environmentalism — a broad political, social, and philosophical movement that advocates various actions and policies in the interest of protecting what nature remains in the natural environment, or restoring or expanding the role of nature in this environment. While true wilderness is increasingly rare, wild nature (e.g., unmanaged forests, uncultivated grasslands, wildlife, wildflowers) can be found in many locations previously inhabited by humans.
Goals commonly expressed by environmentalists include reduction and clean up of man-made pollution, with future goals of zero pollution; reducing societal consumption of non-renewable fuels; development of alternative, green, low-carbon or renewable energy sources; conservation and sustainable use of scarce resources such as water, land, and air; protection of representative or unique or pristine ecosystems; preservation and expansion of threatened or endangered species or ecosystems from extinction; the establishment of nature and biosphere reserves under various types of protection; and, most generally, the protection of biodiversity and ecosystems upon which all human and other life on earth depends.
More recently, there has been a strong concern about climate change such as global warming caused by anthropogenic releases of greenhouse gases, most notably carbon dioxide, and their interactions with humans and the natural environment. Efforts here have focused on the mitigation of greenhouse gases that are causing climatic changes (e.g. through the Climate Change Convention and the Kyoto Protocol), and on developing adaptative strategies to assist species, ecosystems, humans, regions and nations in adjusting to the Effects of global warming.
A more profound challenge, however, is to identify the natural environmental dynamics in contrast to environmental changes not within natural variances. A common solution is to adapt a static view neglecting natural variances to exist. Methodologically this view could be defended when looking at processes which change slowly and short time series, while the problem arrives when fast processes turns essential in the object of the study.

Pollution by Petroleum

Environmental Pollution
Petroleum-derived contaminants constitute one of the most prevalent sources of environmental degradation in the industrialized world. In large concentrations, the hydrocarbon molecules that make up crude oil and petroleum products are highly toxic to many organisms, including humans. Petroleum also contains trace amounts of sulfur and nitrogen compounds, which are dangerous by themselves and can react with the environment to produce secondary poisonous chemicals. The dominance of petroleum products in the United States and the world economy creates the conditions for distributing large amounts of these toxins into populated areas and ecosystems around the globe.

Smoke is pouring from a refinery burnoff vent. (
© Royalty-Free/Corbis. Reproduced by permission.)
Oil Spills
Perhaps the most visible source of petroleum pollution are the catastrophic oil-tanker spills—like the 1989 Exxon Valdez spill in Prince William Sound, Alaska—that make news headlines and provide disheartening pictures of oilcoated shorelines and dead or oiled birds and sea animals. These spills occur during the transportation of crude oil from exporting to importing nations. Crude oil travels for long distances by either ocean tanker or land pipeline, and both methods are prone to accidents. Oil may also spill at the site where it is extracted, as in the case of a blowout like the Ixtoc I exploratory well in 1979 (see table "Ten Largest Oil Spills in History"). A blowout is one of the major risks of drilling for oil. It occurs when gas trapped inside the deposit is at such a high pressure that oil suddenly erupts out of the drill shaft in a geyser.
Accidents with tankers, pipelines, and oil wells release massive quantities of petroleum into land and marine ecosystems in a concentrated form. The ecological impacts of large spills like these have only been studied for a very

World Oil Price 1970-2000 (
World Oil Market and Price Chronologies DOE Energy Information Administration; originally published by the Department of Energy's Office of the Strategic Petroleum Reserve, Analysis Division) few cases, and it is not possible to say which have been the most environmentally damaging accidents in history. A large oil spill in the open ocean may do less harm to marine organisms than a small spill near the shore. The Exxon Valdez disaster created a huge ecological disaster not because of the volume of oil spilled (eleven million gallons) but because of the amount of shoreline affected, the sensitivity and abundance of organisms in the area, and the physical characteristics of the Prince William Sound, which helped to amplify the damage. The Exxon Valdez spill sparked the most comprehensive and costly cleanup effort ever attempted, and called more public attention to oil accidents than ever before. Scientific studies of the effects of oil in Prince William Sound are ongoing, and the number of tanker accidents worldwide has decreased significantly since the time of the Valdez spill, due to stricter regulations and such required improvements in vessel design as double-hull construction.