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Does human behaviour that is caused by inheritance depend on the environment and lifestyle in general?

Does human behaviour that is caused by inheritance depend on the environment and lifestyle in general?



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Different breeds of common domesticated animals such as horses and dogs clearly show different behaviour, instincts, social relationships and similar, due to their biological inheritance. Still they can easily mate with other breeds of the same species. This also applies to wild animals, for example the wolfs living in the rainforest on the Canadian west coast prey on fish (and are maybe expected, with time, to go through a similar transformation as the predecessor to dolphins, that where actually wolf like animals, did when they resettled to the oceans) while inland wolfs prey on moose and elk etc, which requires completely different hunting technique, tactics, pack size and so on.

Are there any similar examples for humans? I reckon that living in the jungle or in the desert or on Greenland should reward different behaviours/traits that influence behaviour. Also going from a hunter-gatherer society to an agricultural society should reward different behaviours, social skills and similar aspect of human life.

Are humans like other animals in this respect (any examples?) or are we unique (?) in the animal kingdom when it comes to the influence of genetics on our behaviour?

One reason I ask is that I got second hand (without sources) information claiming that the natives of Mexico has the highest prevalence, of any population measured, of genes that are known to be connected with/causing ADHD. Mexico was also one the last places on the planet where humankind settled.

The argument went something like this: "during prehistoric time individuals with ADHD tendencies tended to be more adventurous than their peers and therefore traveled further". If this is true, people in Mexico's behaviour should be slightly different from people in current Kenya and Tanzania (by many scientists claimed to the birthplace of humankind), at least if you measure ADHD related traits.


I feel that 99% of the time that someone asks "are human unique concerning ?", the answer is nope. There's nothing exceptional about humans in this respect.

Rephrasing your question

Your question can be rephrased

Is heritability sometimes different from 0 or 1 for humans too?

If you do not understand well why this is a good rephrasing of your question, then you should definitely have a look at this post.

Is heritability sometimes different from 0 or 1 for humans too?

Yes, humans are not exceptional in this regard. In humans, other animals, plants, fungi, bacteria, archeabacteria and for any other living things, any behaviour (and any phenotypic trait in fact) can have a heritability that differs from both 0 and 1, or in other words, there can be for any trait both genetic and environmental variance underlying phenotypic variance in the population.

In fact, very few traits that have a non-zero genetic variance has no environmental variance. Have a look at the post List of heritability estimates in humans? for a list of traits on which we measured heritability.

ADHD

The difficulty with a trait like ADHD is that the methodology to measure it vary a lot from one country to another or even from one practitioner to another. But yes, for ADHD too, there is both genetic and environmental variance underlying the observe phenotypic variance (Thapar et al., 2000).


As @Remi.b said (I upvoted, by the way), humans are rarely completely unique. The first law of behavioral genetics is that all behavioral traits show non-zero genetic influence (This is one of the most replicated findings in the field). More precisely, heritability estimates of behavioral traits are larger than zero, $h^2>0$ (but smaller than one, therefore environmental differences also contribute to the variance of the phenotype).

Population Differences

You say the following:

Different breeds of common domesticated animals such as horses and dogs clearly show different behaviour, instincts, social relationships and similar, due to their biological inheritance. Still they can easily mate with other breeds of the same species.

Then you question whether humans are different in this way. As you noted, it is a socially sensitive topic, but influential geneticist David Reich has very recently written an opinion piece on this sensitive topic (which I suggest you read in full, given your question).

For example, here is a quote by Reich:

While most people will agree that finding a genetic explanation for an elevated rate of disease is important, they often draw the line there. Finding genetic influences on a propensity for disease is one thing, they argue, but looking for such influences on behavior and cognition is another.

But whether we like it or not, that line has already been crossed. [… ]

Regarding population differences:

And since all traits influenced by genetics are expected to differ across populations (because the frequencies of genetic variations are rarely exactly the same across populations), the genetic influences on behavior and cognition will differ across populations, too.

Attention deficit hyperactivity disorder

I have not looked into the genetics of ADHD. It is possible that native Mexicans have a higher rate of ADHD-increasing alleles -- I simply don't know. However, I would suggest you don't completely accept this claim without good sources from primary literature (Also the evolutionary "story" for this claim didn't sound too convincing, in my opinion. However, that may just be because you've been given a weak version of the argument). As with anything, the variance in ADHD is partially due to genetic differences.


Scientists Agree: Global Warming is Happening and Humans are the Primary Cause

The evidence is overwhelming. Record-breaking temperatures, humidity, and sea level rise, along with many other indicators, show that the Earth is warming fast, and that all the heat-trapping emissions we release into the atmosphere from burning fossil fuels is changing our climate.

The Climate Accountability Scorecard

The time to act is now. But action isn't easy: many powerful industry interests have hindered climate solutions and spread dangerous myths about climate change.

One of the preferred tactics these groups use to sow confusion is to promote studies that either ignore or misrepresent the evidence of thousands of articles published in well-established and well-respected scientific journals, which show that global warming is happening and that it is caused by humans.

No matter how much contrarians try to cloak reality, the evidence is not going away.


Human Development

The environment can be a powerful modifier of the normal development and behavior of humans. Environmental effects on development include reduction in IQ from exposure to heavy metals such as lead, changes in puberty from exposure to endocrine disrupting chemicals, birth defects, and fetal loss. Birth defects are the leading cause of death in children, and those born with birth defects have a greater risk of illness and long-term disability than those born without birth defects. Environmental exposure during the most critical developmental times, such as preconception, pre-implantation, the fetal period, and early childhood, can lead to functional loss and developmental changes through genetic mutations and epigenetic change, among other mechanisms. Consequences of developmental changes include a lifetime of suffering and significant society costs in terms of resources, medical care, and lost productivity.

Health Impacts

  • Foodborne illness and food insecurity leads to malnutrition. Nutritional reductions to a developing fetus have lasting effects throughout life. Malnutrition and under-nutrition during pregnancy are a global cause of low birth weight and later developmental deficits
  • Changes in the patterns and concentration of contaminants, such as mercury and lead, entering the marine environment can increase contaminations in seafood, which can lead to developmental effects including a reduction in IQ of the developing fetus
  • Increase in weeds and pests leads to an increase in the use of herbicides and pesticides, resulting in increased exposure and increasing the risk of developmental changes
  • Increase in prevalence of certain toxins, including certain metals, inorganic arsenic, PCBs, persistent organic compounds, in human environments as released by extreme weather events. These toxins have been known to be human carcinogens and can alter the immune system.
  • Increases in the frequency and location of harmful algal blooms, increasing the amount of biotoxins in fish and seafood, leading to developmental effects if eaten by a pregnant woman

Mitigation and Adaptation

  • Access to prenatal care and to early intervention services will be critical in preventing and treating birth defects.
  • In areas where the availability of water is a concern, alternative water sources or reusing water can result in water of a lower quality, which can result in the additional use of toxic chemicals.
  • Changes in energy source policies to reduce increase exposures to airborne metal particulates

Research Needs

  • Understanding the impacts of changes in weather patterns and ecosystems on the incidence, exposure, and distribution of chemical contaminants and biotoxins known to cause developmental disorders
  • Expanding the use of marine species as biomedical models and sentinels for understanding effects of contaminants and biotoxins on human reproduction and development
  • Understanding the implications of mitigation strategies, including changes in energy policies and new technologies, on the production, use, and storage of heavy metals and chemicals that are known to cause developmental disorders

For more information, please visit the chapter on Human Developmental Effects in A Human Health Perspective on Climate Change (Full Report) (4MB) .


Negatives of Human activities on environment:

Pollution
Firstly we can consider the foremost problem. I.e. POLLUTION. It is so evident that, humans dump a lot of waste in the environment, leaving the land dwelling species to succumb to death. And also their activities release, many harmful gases. And not only air, we are continuously depleting the quality of soil, water, not leaving any element. This behavior of humans actually acts as a mirror. It reflects totally on to the humans again. Due to which we will not have proper ventilation, pure air, water. Already there is a large sector of people, who are not having clean drinking water. We are destroying ourselves.

We will buy air also
Olden days, they used to laugh when someone predicted, “we have to buy water someday in the future” they were glad about this, but now we are doing the same. We are actually buying water. And one day we will reach to that level of destruction of nature, that we will buy oxygen as well. If this continues, everyone will be having one oxygen pump.

Acid rain
We have heard a lot about acid rains, all this is due to humans again. When nitrogen oxides, sulphur oxides, carbon oxides are released in to the atmosphere, they go and accumulate in the clouds. And when it rains, it is not the water droplets but it is saturated form of these harmful gases. These harmful solvents come and settle on water bodies, causing death of many water dwelling animals. It is actually a slow poison to all species.

Ozone layer depletion
Ozone layer which helps in protecting the earth from harmful U.V rays emitted by the sun, is now getting depleted. We are already seeing the effects, we can’t imagine our earth without it, and we can’t step out of our homes. But still, we have time for regaining the ozone layer, ad advanced theories are coming up to solve this problem, it will take really longer time for us to do so. So, until then we have to be very careful.

As we are the species who can speak, care, memorize, think. We should contribute a larger helping nature to the other species, which cannot do it for themselves.

Labels:possitive impact of people in terrestrial ecosystem, 3 positive impact human have on the environment, 4 negative effects of human, 5 examples of ways that human activity harms the environment, ways humans can affect orgnisms and the environment in the ocean in a positive way, effects of environment to man,


How have we changed since our species first appeared?

Click to enlarge image Toggle Caption

Overview

We have undergone change since our species first evolved. Some changes were universal whereas others were more regional in effect. The changes apparent in worldwide populations include a decrease in both overall body size and brain size as well as a reduction in jaw and tooth proportions. Regional populations have also evolved different physical and genetic characteristics in response to varying climates and lifestyles.

Smaller bodies

We are now generally shorter, lighter and smaller boned than our ancestors were 100,000 years ago. The decrease has been gradual but has been most noticeable in the last 10,000 years. However, there has been some slight reversal to this trend in the last few centuries as the average height has started to increase.

The factors that affect body size are complex. They involve interactions between genetics, environment and lifestyle practices such as diet and technology.

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Average height of Homo sapiens over the last 40,000 years

This information is based on the average heights of European males because better statistics exist for this population, but the general trend is worldwide.

  • 40,000 years ago: European males – 183 cm (6 feet). Cro-Magnon people were the first modern humans (Homo sapiens) to inhabit Europe. These hunter-gatherers lived a physically demanding lifestyle that would have required greater body strength than the average human today. Their recent African ancestry may have also affected their height, as tall, long-limbed builds are useful adaptations to the warmer African climate.
  • 10,000 years ago: European males – 162.5cm (5 ft 4 inches). A dramatic reduction in the size of humans occurred at this time. Many scientists think that this reduction was influenced by global climatic change and the adoption of agriculture. Agricultural communities suffered from malnutrition as a result of failed crops and a more restricted diet. Furthermore, a close association with domestic livestock introduced new diseases into human populations.
  • 600 years ago: European males – 165 cm (5 ft 5 inches). Poor diet and health were the main causes for the shorter stature at this time.
  • Today: European males – 175 cm (5ft 9 inches). There has been an increase in height over the last few hundred years. In part, this increase is due to improved diet and health care. There may also be a genetic link as industrial expansion and urbanisation has brought together genetically isolated people and reduced the impacts of inbreeding due to a greater mixing of populations and their genes.

Smaller brains

For the last two million years there has been a trend toward a bigger brain that has affected many species in our family tree. This trend has seen a reversal in our own species and our brains are now the smallest they have been at any time in the past 100,000 years. Most of this decrease occurred in the last 6,000 years. In part, this is related to a decrease in body size that also occurred during this period, however, other factors are probably also involved.

Our brains now average about 100-150 cubic centimetres less than when our species first appeared.

  • 100,000 years ago: average brain size: 1500cc
  • 12,000 years ago: average brain size: 1450cc
  • Today: average brain size: 1350cc

Smaller teeth and jaws

The trend toward smaller jaws and teeth that was seen in our ancestors has continued in our own species. In fact, some people today do not have enough space in their jaws to fit their 3rd molars or wisdom teeth.

Overall, these changes have occurred in proportion with a decrease in body size. However, over the last 10,000 years dietary changes and technology have played a major role.

A decrease in size has occurred in the jaws and teeth of Homo sapiens over the last 30,000 years. However, there has been a very slight reversal in this trend in the last century as teeth have increased in size. This is partly related to the introduction of fluoride, which thickens dental enamel, so making teeth a little larger.

Developing physical diversity: All one species but looking different

Humans today show an enormous diversity in appearance, however this diversity was not apparent in early Homo sapiens. Early members of our species lived in Africa and had evolved physical characteristics that were similar to each other in order to survive in that climate. When humans started to spread to different parts of the world about 100,000 years ago, they encountered a variety of different climatic conditions and evolved new physical adaptations more suitable to those new climates.

Recent DNA studies (since 2007) confirm that genetic traits have changed or adapted to new environments during this time. In fact, the rate of change of DNA, and thus the rate of evolution, has accelerated in the last 40,000 years. Areas of the human genome still seem to be undergoing selection for things such as disease and skin colour.

It also appears that some physical features have been inherited from interbreeding with other ancient human species. An international team, led from CL, Aix-Marseille University and the Open University, found the the gene TBX15 was linked with genes found in ancient Denisovans, providing a clue to the origin of the gene in our species. This gene helps determine lip shape via body fat distribution and may have been useful to Denisovans in the cold climates of their Central Asian homelands.

Physical characteristics such as skin and eye colour, hair type and colour and body shape are determined by genetics, but can also be influenced by the environment. Over long periods of time, the environment will act on the genes to develop particular characteristics within a population.

All one species – how climate affects physical characteristics

  • Body builds: Short, stocky builds are typical of humans living in cold climates. The reduced surface area compared to weight allows more body heat to be retained. A thin, long-limbed build is typical of humans in hot regions. The larger skin surface compared to weight allows for body heat to be lost more easily.
  • Skin colour: Lighter skin allows the penetration of the sun’s UV rays. These rays help the body to synthesise vitamin D. Darker skin protects the body from absorbing too many UV rays. This can cause cancer or destroy important vitamins and minerals.
  • Noses: People living in hot, humid climates tend to have broad, flat noses that allow inhaled air to be moistened and the moisture in exhaled air to be retained. People living in hot, dry climates typically have narrowed, projecting noses. This type of nose reduces the amount of water that is lost from the lungs during breathing. People living in cold, dry climates generally have smaller, longer and narrower noses. This type of nose moistens and warms the incoming air.
  • Hair: Tight, curly hair keeps the hair off the neck and exposes more areas of the scalp than straight hair. This helps with cooling and evaporation of sweat. Straight hair is common in people living in colder climates as it keeps the neck and head warm. Straight hair also allows cold moisture to run off the scalp more easily.
  • Face shape: Inuits have adapted to extreme cold by retaining layers of fat on their faces for additional warmth. Populations in northern Asia and the Arctic tend to have broad, flat faces as these reduce the effects of frostbite.
  • Mouth shape: Thick lips have a larger surface area to help evaporate moisture and cool the body. The larger surface also allows cooling by moistening of the lips.
  • Eyes: The epicanthic fold common among Northern and Eastern Asian populations is an adaptation for protecting the eye from the hard driving snow typical in these regions, and also to reduce snow glare. Blue eyes are better adapted for vision in regions where there is reduced light, as they let in more light than darker coloured eyes.
  • Additional: Australian Aboriginals of the Central Desert have an unusual physical adaptation to living in a climate where it can be freezing for short periods, such as during cold desert nights. They have evolved the ability to drop their bodies to low temperatures without triggering the usual reflex of shivering.

Bonfante B et al. ɺ GWAS in Latin Americans identifies novel face shape loci, implicating VPS13B and a Denisovan introgressed region in facial variation', Science Advances volume 7 (2021)


Human genetic adaptations and human variation

Skin color

Click on this link to watch a fantastic video explaining the interplay of skin color, UV, and vitamin D.

Body size and shape

There are two ecological rules, known as Bergmann’s rule and Allen’s rule, that explain the variation in size and shape of bodies and extremities using latitude and temperature.

Bergmann’s rule: Warm-blooded animals tend to have increasing body size with increasing latitude (toward the poles) and decreasing average temperatures.

Allen’s rule: A corollary of Bergmann’s rule that applies to appendages. Warm-blooded animals tend to have shorter limbs with increasing latitude and decreasing average temperatures.

When organisms are more compact, they tend to conserve heat (due to a high mass:surface area ratio). When organisms are more linear, they tend to lose more heat (due to a low mass:surface area ratio).

This has been applied to humans. The idea is that populations toward the pole tend to be shorter and have shorter limbs than do people on the equator.

For example, the Inuit people of Canada (pictured above) tend to be shorter than the Maasai people of Kenya (pictured below):


There is evidence to suggest that human activities have caused the amount of carbon dioxide in our atmosphere to rise dramatically. This impacts on the marine environment as the world’s oceans currently absorb as much as one-third of all CO2 emissions in our atmosphere. This absorption of CO2 causes the pH to decrease, resulting in the seawater becoming more acidic.

Scientists have long understood that an increase in carbon dioxide in the atmosphere will result in higher levels of dissolved CO2 in seawater. However, a relatively recent discovery is that even small changes in water pH can have big impacts on marine biology. Ocean acidification is a worldwide issue, but as CO2 is more soluble in colder water, it is of particular concern in New Zealand’s temperate oceans.

It is difficult to predict the overall impact on the marine ecosystem but many scientists fear that ocean acidification has the potential to decrease marine biodiversity on a very large scale.

New Zealanders are aware that old ways of managing our seas are in need of a rethink. The Sustainable Seas National Science Challenge is tasked with helping New Zealand enhance the value of our marine resources while ensuring they are safeguarded for future generations.


Simple Recycling

Ecosystems are biological communities and exist all around the globe. They serve as small, interconnected worlds that host multiple forms of plant and animal life. Nature recycles everything: Dead plant and animal matter return to the soil to once again produce more trees and plants. Taking a cue from nature, many people understand that recycling offers a positive contribution to the ecosystems of the world by reusing or remaking old products into new ones without having to take resources from nature.


Toward an Interdisciplinary Perspective of Human and Ecosystem Health

Since the late nineteenth century, a number of descriptive models have been developed to encapsulate the dimensions of human health and the natural environment as well as their interrelationships (17). These include the Environment of Health (11), the Mandala of Health (12), the Wheel of Fundamental Human Needs (13), and the Healthy Communities (14). As VanLeeuwen et al (17) highlight in their review, each have not fully incorporated all relevant characteristics of ecosystems (e.g., multiple species, trade-offs, and feedback loops, as well as the complex interrelationships between socioeconomic and biophysical environments). Further, the Bioecological systems theory model encapsulates the biopsychological characteristics of an evolving theoretical system for scientific study of human development over time (16, 132). However, the model has been suggested by some (133, 134) to be static and compartmentalized in nature, emphasizing instead the importance of evolving synergies between biology, culture, and technology.

More recently, the concept “One Health” has gradually evolved and increased with momentum across various disciplines (15). It is broadly defined as the attainment of optimal health across the human𠄺nimal𠄾nvironmental interfaces at local, national, and global levels. It calls for a holistic and universal approach to researching health, an ideology said to be traceable to pathologist Rudolf Virchow in 1858 (18). Yet, the concept has received criticisms regarding its prominence toward the more biological phenomena (e.g., infectious diseases) than those of a social science and spatial perspective (18, 135). Some have therefore suggested its need to adopt an interdisciplinary approach to facilitate a deeper understanding of the complexities involved (13).

To address these limitations identified in the above models, a suggested conceptual model has been outlined below (Figure 1). It is both inclusive of all relevant characteristics of ecosystems, their continuously evolving synergies with human health as well as a balance between the biological, social, and spatial perspectives. This is achieved through combining the perspective of the human–nature relationship, as summarized in Section �ining the Human–Nature Relationship” of this review, with those human-centered components of health (physical, mental, and social), as defined by the World Health Organization in 1948 in Section �ining Health.” It aims to facilitate a deeper understanding of the complexities involved for attaining optimal human health (19). I will now describe the conceptual model.

Figure 1. Interdisciplinary perspective of human and ecosystem health [image on the inside circle is by Baird (136) with the background image, added text, and embedded illustrations being the author’s own work].

First, the outer circle is representative of “nature” that both encompasses and interconnects with the three human-centered components of health (physical, mental, and social). Through this it emphasizes humanity’s interrelationship with the environment. As identified in Section �ining the Human–Nature Relationship” of this review, the human–nature relationship can be experienced through various biological, ecological, and behavioral connections. For instance, social, political, and economic issues stemming from humanity’s interactions affecting the natural environment (e.g., natural resources, environmental hazards, habitat management, and restoration), as explored in Subsections “Social Economics” and 𠇎nvironmentalism.”

Second, in the inner circle, the three components of human health (physical, mental, and social) are interconnected through a cohesive triangle to reflect their interdisciplinary and dynamic natures, as outlined in Section �ining Health.” Further, this cohesive triangle acts on two levels. First, as a single construct of health based on these components combined. Second, the underlying intervening mechanisms that sustain or inhibit health, which can derive from each of these separately (105). Thereby, it not only focuses on the outcomes or “recuperative measure” of health but also the source of such outcomes and their directions, as highlighted in Section “Mental Health” (104).

The middle circle represents the interconnected relationship between humanity and the natural environment with relevance to human health (see Current Knowledge on the Human–Nature Relationship and Health). This has been indicated by the two-way arrows and incorporates Gual and Norgaard’s (31) coevolutionary perspective between human adaptation and the natural environment. In this way, the relationship is continually interconnected via two-way physical and perceptual interactions. These are embedded within three integrated systems (biophysical, biotic, and cultural), with all humanity knows of the world comes through such mediums (31). As such, the human–nature relationship goes beyond the extent to which an individual believes or feels they are affiliated with nature (e.g., Biophilia concept). It can also be understood as, and inclusive of, our adaptive synergy with nature as well as our longstanding actions and experiences that connect us to nature.

Utilizing this developing conceptual model, methodological approaches can be employed from those research fields explored in this review, enabling a more interdisciplinary framework. The characteristics, descriptions, implications, and practicalities of this are detailed in Table 2 below. The advantage of this is that a multitude of knowledge from both rigorous scientific analysis as well as collaborative participatory research can be combined bringing a greater depth to data collected (114). This could be achieved through using more mixed-method approaches and adopting a pragmatic outlook in research. In this way, the true social, economic, and political diversity of “real life” as well as the optimal human health at the human𠄾nvironmental interface can be identified. As such, a more multidimensional perspective of human health would be gained, knowledge that could be implemented to address those issues identified in Section “Impacts of the Human–Nature Relationship on Health” (e.g., improving nature and health ecosystem service accounting). Nonetheless, adopting a pragmatic outlook brings its own challenges, as explored by Onwuegbuzie and Leech (137), with several researchers proposing frameworks that could be implemented to address these concerns (138, 139).

Table 2. A summarized overview of human and ecosystem health from an interdisciplinary perspective.


Mr. Kousen is. Water Man H UMAN I MPACT ON THE N ATURAL E NVIRONMENT

State of ecosystems, habitats and species
In the past, human interaction with nature, although often having a disruptive effect on nature, often also enriched the quality and variety of the living world and its habitats - e.g. through the creation of artificial landscapes and soil cultivation by local farmers.

  • intensive agriculture replacing traditional farming this combined with the subsidies of industrial farming has had an enormous effect on western rural landscapes and continues to be a threat.
  • mass tourism affecting mountains and coasts.
  • the policies pursued in the industry, transport and energy sectors having a direct and damaging impact on the coasts, major rivers (dam construction and associated canal building) and mountain landscapes (main road networks).
  • the strong focus of forestry management on economic targets primarily causes the decline in biodiversity, soil erosion and other related effects.
  • Reduction and fragmentation of habitats and landscapes
    The expansion of humans activities into the natural environment, manifested by urbanisation, recreation, industrialisation, and agriculture, results in increasing uniformity in landscapes and consequential reduction, disappearance, fragmentation or isolation of habitats and landscapes.
    It is evident that the increasing exploitation of land for human use greatly reduces the area of each wildlife habitat as well as the total area surface throughout Europe. The consequences are:
    • A decreased species diversity, due to reduced habitable surface area which corresponds to a reduced "species carrying capacity".
    • The reduction of the size of habitats also reduces the genetic diversity of the species living there. Smaller habitats can only accommodate smaller populations, this results in an impoverished gene pool.
    • The reduction of genetic resources of a species diminishes its flexibility and evolutionary adaptability to changing situations. This has significant negative impacts on its survival.
    • The abrupt nature of human intervention human projects are planned and implemented on a much shorter time scale than natural processes
    • Furthermore human intervention, such as the construction of buildings, motorways or railways results in the fragmentation of habitats, which strongly limits the possibility for contact or migration among them
    • In extreme cases even the smallest, narrowest connections between habitats are broken off. Such isolation is catastrophic for life in the habitat fragments.

    Europe's natural environment is inextricably linked with agriculture and forestry. Since agriculture traditionally depends on sound environmental conditions, farmers have a special interest in the maintenance of natural resources and for centuries maintained a mosaic of landscapes which protected and enriched the natural environment.

    As a result of needs for food production since the 1940s, policies have encouraged increased pro- duction through a variety of mechanisms, including price support, other subsidies and support for research and development. The success achieved in agricultural production has however entailed increased impact on the environment.

    Modern agriculture is responsible for the loss of much wildlife and their habitats in Europe, through reduction and fragmentation of habitats and wildlife populations. The drainage of wetlands, the destruction of hedgerows and the intensive use of fertilizers and pesticides can all pose a threat to wildlife. Highly specialised monoculture are causing significant loss in species abundance and diversity. On the other hand increased production per hectare in intensive areas, raising of livestock volume, and lower prices for agricultural products also caused marginalization of agricultural land, changing the diversity of European landscapes into the direction of two main types: Intensive Agriculture and Abandoned land.

    Abandonment can be positive for nature, but this is not necessarily so. Land abandonment increases the risk of fire in the Mediterranean Region, causes a decline of small-scale landscape diversity and can also cause decrease in species diversity.

    All energy types have potential impacts on the natural environment to varying degrees at all stages of use, from extraction through processing to end use. Generating energy from any source involves making the choices between impacts and how far those impacts can be tolerated at the local and global scale. This is especially of importance for nuclear power, where there are significant risks of radioactive pollution such as at Chernobyl.

    Shell Oil Company and IUCN have jointly drafted environmental regulations for oil-exploitation in Arctic areas of Siberia. Other oil companies are aware of this and use these environmental regula- tions voluntarily for developing oil fields.

    Into the future the sustainability of the natural environment will be improved as trends away from damaging energy uses and extractive methods reduce and whilst real cost market forces and the polluter pays principle take effect.

    The principle of the fisheries sector is towards sustainable catches of wild aquatic fauna. The principle environmental impact associated with fisheries activities is the unsustainable har- vesting of fish stocks and shellfish and has consequences for the ecological balance of the aquatic environment. The sector is in a state of "crisis", with over capacity of the fleet, overexploitation of stocks, debt, and marketing problems.
    Growing aquaculture industry may increase water pollution in western Europe, and is appearing to be a rising trend in the Mediterranean and Central/East Europe.

    Fishing activities have an impact on cetaceans and there is concern that large numbers of dolphins, and even the globally endangered Monk seal, are being killed.

    Compared to other landuses, forest management has the longest tradition in following sustainable principles due to which over 30% of Europe is still covered with trees. Without such an organised approach, forests are likely to have already disappeared from Europe's lowlands. However, as an economic sector, forestry has also impacted severely on the naturalness of Europe's forests: soils have been drained, pesticides and fertilizers applied, and exotic species planted. In many areas monocultures have replaced the original diverse forest composition. Monocultures are extremely sensitive to insect infestations, fires or wind, and so can lead to financial losses as well as biological decline. The inadequate afforestation practices characterize new trends in impacting on the sustainability of the natural environment.

    Almost all forms of industry have an impact on the natural environment and its sustainability. The impact varies at different stages in the life cycle of a product, depending upon the raw materials used through to the final end use of the product for waste residue, re-use or recycling. Industrial accidents and war damage to industrial plants can also endanger the natural environment.

    Tourism and Recreation

    Tourism and recreation impact in various ways on the natural environment. On the one hand, natural areas form the very basis of many touristic attractions by highlighting scenic value or exceptional encounters with fauna and flora. However, some forms of tourism can be extremely detrimental to ecologically sensitive areas, resulting in habitat degeneration or destruction, in the disturbance or hunting even rare or threatened species. The pressure from short holiday seasons and specific, sometimes small, locations of touristic interest result in conflicting land-uses, such as in the Alpine regions, at Mediterranean beaches and along many banks of inland waters.

    Transport and Infrastructure

    Transport is perhaps the major contributor to pollution in the world today, particularly global envi- ronmental issues such as the greenhouse effect. The key impacts of transportation include frag- mentation of habitats and species and genetic populations, disruption of migration and traffic mortalities to wildlife. Since the 1970s transport has become a major consumer of non-renewable resources, 80% of oil consumption coming from road transport.