Biodiversity is the variation of
life forms within a given
ecosystem,
biome, or for the
entire
Earth. Biodiversity is often used as a
measure of the health of
biological
systems. The biodiversity found on Earth today consists of many
millions of distinct biological
species,
which is the product of nearly 3.5 billion years of
evolution.
2010 is the
International Year of
Biodiversity.
Etymology
The term was used first by wildlife scientist and conservationist
Raymond F. Dasmann in a lay book advocating nature conservation.
The term was not widely adopted for more than a decade, when in the
1980s it and "biodiversity" came into common usage in science and
environmental policy. Use of the term by
Thomas Lovejoy in the Foreword to the book
credited with launching the field of
conservation biology introduced the
term along with "
conservation
biology" to the scientific community. Until then the term
"natural diversity" was used in conservation science circles,
including by The Science Division of
The Nature Conservancy in an
important 1975 study, "The Preservation of Natural Diversity." By
the early 1980s TNC's Science program and its head
Robert
E. Jenkins, Lovejoy, and other leading conservation
scientists at the time in America advocated the use of "biological
diversity" to embrace the object of biological conservation.
The term's contracted form
biodiversity may have been
coined by W.G. Rosen in 1985 while planning the
National Forum
on Biological Diversity organized by the
National Research
Council (NRC) which was to be held in 1986, and first appeared
in a publication in 1988 when entomologist
E. O. Wilson used it as the title of the
proceedings of that forum.
Since this period both terms and the concept have achieved
widespread use among biologists, environmentalists, political
leaders, and concerned citizens worldwide. The term is sometimes
used to equate to a concern for the natural environment and nature
conservation. This use has coincided with the expansion of concern
over
extinction observed in the last
decades of the 20th century.
A similar concept in use in the United States, besides natural
diversity, is the term "natural heritage." It pre-dates both terms
though it is a less scientific term and more easily comprehended in
some ways by the wider audience interested in conservation.
Furthermore it may be misleading if used to refer only to
biodiversity, as natural heritage also includes geology and
landforms (geodiversity). The term "Natural Heritage" was used when
Jimmy Carter set up the Georgia
Heritage Trust while he was governor of Georgia; Carter's trust
dealt with both natural and
cultural
heritage. It would appear that Carter picked the term up from
Lyndon Johnson, who used it in a 1966
Message to Congress. "Natural Heritage" was picked up by the
Science Division of the US
Nature
Conservancy when, under Jenkins, it launched in 1974 the
network of State Natural Heritage Programs.
When this network was
extended outside the USA
, the term "Conservation Data Center" was suggested
by Guillermo Mann and came to be preferred.
Definitions
"Biological diversity" or "biodiversity" can have many
interpretations and it is most commonly used to replace the more
clearly defined and long established terms,
species diversity and
species richness. Biologists most often
define biodiversity as the "totality of genes, species, and
ecosystems of a region". An advantage of this definition is that it
seems to describe most circumstances and present a unified view of
the traditional three levels at which biological variety has been
identified:
This multilevel conception is consistent with the early use of
"biological diversity" in Washington. D.C. and international
conservation organizations in the late 1960s through 1970's, by
Raymond F. Dasmann who apparently coined the term and Thomas E.
Lovejoy who later introduced it to the wider conservation and
science communities. An explicit definition consistent with this
interpretation was first given in a paper by Bruce A. Wilcox
commissioned by the
International Union for the Conservation of Nature and Natural
Resources (IUCN) for the 1982 World National Parks Conference
in Bali The definition Wilcox gave is "Biological diversity is the
variety of life forms...at all levels of biological systems (i.e.,
molecular, organismic, population, species and ecosystem)..."
Subsequently, the 1992 United Nations Earth
Summit in Rio de
Janeiro
defined "biological diversity" as "the variability
among living organisms from all sources, including, 'inter alia',
terrestrial, marine, and other aquatic ecosystems, and the ecological
complexes of which they are part: this includes diversity within
species, between species and of ecosystems". This is, in
fact, the closest thing to a single legally accepted definition of
biodiversity, since it is the definition adopted by the United
Nations
Convention on
Biological Diversity.
The current textbook definition of "biodiversity" is "variation of
life at all levels of biological organization".
For
geneticists,
biodiversity is
the diversity of genes and
organisms. They
study processes such as mutations, gene exchanges, and genome
dynamics that occur at the DNA level and generate evolution.
Consistent with this, along with the above definition the Wilcox
paper stated "genes are the ultimate source of biological
organization at all levels of biological systems..."
Measurement
A variety of objective measures have been created in order to
empirically measure biodiversity. Each measure of biodiversity
relates to a particular use of the data. For practical
conservationists, measurements should include a quantification of
values that are commonly-shared among locally affected organisms,
including humans. For others, a more economically defensible
definition should allow the ensuring of continued possibilities for
both adaptation and future use by humans, assuring environmental
sustainability.
Distribution
Selection bias continues to bedevil
modern estimates of biodiversity. In 1768 Rev.
Gilbert White succinctly observed of his
Selborne,
Hampshire
"all nature is so full, that that district produces
the most variety which is the most examined."
Nevertheless, biodiversity is not distributed evenly on Earth.
It is
consistently richer in the tropics and in
other localized regions such as the Cape Floristic
Province
. As one approaches polar regions one
generally finds fewer species. Flora and fauna diversity depends on
climate, altitude,
soils
and the presence of other species. In the year 2006 large numbers
of the Earth's species were formally classified as
rare or
endangered or
threatened species; moreover, many
scientists have estimated that there are millions more species
actually endangered which have not yet been formally recognized.
About 40 percent of the 40,177 species assessed using the
IUCN Red List criteria, are now listed as
threatened species with
extinction - a total of 16,119 species.
Even though biodiversity declines from the equator to the poles in
terrestrial ecoregions,
whether this is so in
aquatic
ecosystems is still a hypothesis to be tested, especially in
marine ecosystems where causes of
this phenomenon are unclear. In addition, particularly in marine
ecosystems, there are several well stated cases where diversity in
higher latitudes actually increases. Therefore, the lack of
information on biodiversity of
Tropics and
Polar Regions prevents scientific
conclusions on the distribution of the world’s aquatic
biodiversity.
A
biodiversity hotspot is a
region with a high level of
endemic
species. These biodiversity hotspots were first identified by Dr.
Norman Myers in two articles in the
scientific journal
The Environmentalist.
Dense human habitation tends to occur near
hotspots. Most hotspots are located in the
tropics and most of them are forests.
Brazil
's Atlantic Forest is considered a hotspot of
biodiversity and contains roughly 20,000 plant species, 1350
vertebrates, and millions of insects, about half of which occur
nowhere else in the world. The island of Madagascar
including the unique Madagascar dry deciduous
forests and lowland rainforests possess a very high ratio of
species endemism and biodiversity, since
the island separated from mainland Africa 65
million years ago, most of the species and ecosystems have evolved
independently producing unique species different from those in
other parts of Africa.
Many regions of high biodiversity (as well as high
endemism) arise from very specialized
habitats which require unusual adaptation
mechanisms. For example the peat
bogs of
Northern
Europe.
Evolution
Biodiversity found on
Earth today is the
result of 4 billion years of
evolution.
The
origin of life has not been
definitely established by science, however some evidence suggests
that life may already have been well-established a few hundred
million years after the
formation of
the Earth. Until approximately 600 million years ago, all life
consisted of
archaea,
bacteria,
protozoans and
similar single-celled organisms.
The history of biodiversity during the
Phanerozoic (the last 540 million years), starts
with rapid growth during the
Cambrian
explosion—a period during which nearly every
phylum of
multicellular organisms first
appeared. Over the next 400 million years or so, global diversity
showed little overall trend, but was marked by periodic, massive
losses of diversity classified as
mass
extinction events.
The apparent biodiversity shown in the
fossil record suggests that the last few
million years include the period of greatest biodiversity in the
Earth's history. However, not all
scientists support this view, since there is considerable
uncertainty as to how strongly the fossil record is biased by the
greater availability and preservation of recent
geologic sections. Some (e.g. Alroy et al. 2001)
argue that, corrected for sampling artifacts, modern biodiversity
is not much different from biodiversity 300 million years ago.
Estimates of the present global macroscopic species diversity vary
from 2 million to 100 million species, with a best estimate of
somewhere near 13–14 million, the vast majority of them
arthropods.
Most biologists agree however that the period since the emergence
of humans is part of a new mass extinction, the
Holocene extinction event, caused
primarily by the impact humans are having on the environment. It
has been argued that the present rate of extinction is sufficient
to eliminate most species on the planet Earth within 100
years.
New species are regularly discovered (on average between 5–10,000
new species each year, most of them
insects)
and many, though discovered, are not yet classified (estimates are
that nearly 90% of all
arthropods are not
yet classified). Most of the terrestrial diversity is found in
tropical forests.
Human benefits
Biodiversity also supports a number of natural ecosystem processes
and services . Some ecosystem services that benefit society are air
quality , climate (both global CO
2 sequestration and
local), water purification pollination, and prevention of
erosion..
Since the stone age, species loss has been accelerated above the
geological rate by human activity. The rate of species extinction
is difficult to estimate, but it has been estimated that species
are now being lost at a rate approximately 100 times as fast as is
typical in the geological record, or perhaps as high as 10 000
times as fast. To feed such a large population, more land is being
transformed from wilderness with wildlife into agricultural,
mining, lumbering, and urban areas for humans.
Non-material benefits that are obtained from ecosystems include
spiritual and aesthetic values , knowledge systems and the value of
education.
Agriculture
The economic value of the reservoir of genetic traits present in
wild varieties and traditionally grown
landraces is extremely important in improving crop
performance . Important crops, such as the potato and coffee, are
often derived from only a few genetic strains . Improvements in
crop plants over the last 250 years have been largely due to
harnessing the genetic diversity present in wild and domestic crop
plants . Interbreeding crops strains with different beneficial
traits has resulted in more than doubling crop production in the
last 50 years as a result of the
Green
Revolution .
Crop diversity is also necessary to
help the system recover when the dominant crop type is attacked by
a disease:
- The Irish potato blight
of 1846, which was a major factor in the deaths of a million people
and migration of another million, was the result of planting only
two potato varieties, both of which were vulnerable.
- When rice grassy stunt
virus struck rice fields from Indonesia to India in the 1970s.
6273 varieties were tested for resistance. One was found to be
resistant, an Indian variety, known to science only since 1966.
This variety formed a hybrid with other varieties and is now widely
grown.
- Coffee rust attacked coffee
plantations in Sri Lanka, Brazil, and Central America in 1970. A
resistant variety was found in Ethiopia. Although the diseases are
themselves a form of biodiversity.
Monoculture, the lack of biodiversity,
was a contributing factor to several agricultural disasters in
history, the European wine industry collapse in the late 1800s, and
the
US Southern Corn Leaf Blight
epidemic of 1970. See also:
Agricultural biodiversity
Higher biodiversity also controls the spread of certain diseases as
pathogens will need to adapt to infect different species .
Biodiversity provides food for humans . Although about 80 percent
of our food supply comes from just 20 kinds of plants , humans use
at least 40,000 species of plants and animals a day . Many people
around the world depend on these species for their food, shelter,
and clothing . There is untapped potential for increasing the range
of food products suitable for human consumption, provided that the
high present extinction rate can be stopped.
Human health

The diverse forest canopy on Barro
Colorado Island, Panama, yielded this display of different
fruit
relevance of biodiversity to human health is becoming a major
international political issue, as scientific evidence builds on the
global health implications of biodiversity loss. This issue is
closely linked with the issue of climate change, as many of the
anticipated health risks of climate change are associated with
changes in biodiversity (e.g. changes in populations and
distribution of disease vectors, scarcity of fresh water, impacts
on agricultural biodiversity and food resources etc). Some of the
health issues influenced by biodiversity include dietary health and
nutrition security, infectious diseases, medical science and
medicinal resources, social and psychological health, and spiritual
well-being. Biodiversity is also known to have an important role in
reducing disaster risk, and in post-disaster relief and recovery
efforts.
One of the key health issues associated with biodiversity is that
of drug discovery and the availability of medicinal resources . A
significant proportion of drugs are derived, directly or
indirectly, from biological sources; Chivian and Bernstein report
that at least 50% of the pharmaceutical compounds on the market in
the US are derived from natural compounds found in plants, animals,
and microorganisms, while about 80% of the world population depends
on medicines from nature (used in either modern or traditional
medical practice) for primary healthcare. Moreover, only a tiny
proportion of the total diversity of wild species has been
investigated for potential sources of new drugs. Through the field
of
bionics, considerable technological
advancement has occurred which would not have without a rich
biodiversity. It has been argued, based on evidence from market
analysis and biodiversity science, that the decline in output from
the pharmaceutical sector since the mid-1980s can be attributed to
a move away from natural product exploration ("bioprospecting") in
favour of R&D programmes based on genomics and synthetic
chemistry, neither of which have yielded the expected product
outputs; meanwhile, there is evidence that natural product
chemistry can provide the basis for innovation which can yield
significant economic and health benefits. Marine ecosystems are of
particular interest in this regard, however unregulated and
inappropriate bioprospecting can be considered a form of
over-exploitation which has the potential to degrade ecosystems and
increase biodiversity loss, as well as impacting on the rights of
the communities and states from which the resources are
taken.
Business and Industry
A wide range of industrial materials are derived directly from
biological resources. These include building materials, fibers,
dyes, resirubber and oil. There is enormous potential for further
research into sustainably utilizing materials from a wider
diversity of organisms. In addition, biodivesity and the ecosystem
goods and services it provides are considered to be fundamental to
healthy economic systems. The degree to which biodiversity supports
business varies between regions and between economic sectors,
however the importance of biodiversity to issues of resource
security (water quantity and quality, timber, paper and fibre, food
and medicinal resources etc) are increasingly recognized as
universal. As a result, the loss of biodiversity is increasingly
recognized as a significant risk factor in business development and
a threat to long term economic sustainability. A number of case
studies recently compiled by the World Resources Institute
demonstrate some of these risks as identified by specific
industries.

Other ecological services
Biodiversity provides many
ecosystem
services that are often not readily visible. It plays a part in
regulating the chemistry of our
atmosphere and
water
supply. Biodiversity is directly involved in
water purification, recycling
nutrients and providing fertile soils. Experiments
with controlled environments have shown that humans cannot easily
build ecosystems to support human needs; for example
insect pollination cannot be mimicked by
human-made construction, and that activity alone represents tens of
billions of dollars in
ecosystem
services per annum to humankind.
The
stability of
ecosystems is also related to biodiversity, with higher
biodiversity producing greater stability over time, reducing the
chance that ecosystem services will be disrupted as a result of
disturbances such as extreme weather events or human
exploitation.
Leisure, cultural and aesthetic value
Many people derive value from biodiversity through leisure
activities such as
hiking,
birdwatching or natural history study.
Biodiversity has inspired
musicians,
painters, sculptors, writers and other artists. Many cultural
groups view themselves as an integral part of the natural world and
show respect for other living organisms.
Popular activities such as gardening, caring for aquariums and
collecting butterflies are all strongly dependent on biodiversity.
The number of species involved in such pursuits is in the tens of
thousands, though the great majority do not enter mainstream
commercialism.
The relationships between the original natural areas of these often
'exotic' animals and plants and commercial collectors, suppliers,
breeders, propagators and those who promote their understanding and
enjoyment are complex and poorly understood. It seems clear,
however, that the general public responds well to exposure to rare
and unusual
organisms—they recognize their
inherent value at some level. A family outing to the
botanical garden or zoo is as much an
aesthetic or cultural experience as it is an educational one.
Philosophically it could be argued that biodiversity has intrinsic
aesthetic and spiritual value to mankind
in and of itself.
This idea can be used as a counterweight to the notion that
tropical forests and other
ecological realms are only worthy of conservation because they may
contain medicines or useful products.
An interesting point is that evolved DNA embodies knowledge, and
therefore destroying a species resembles burning a book, with the
caveat that the book is of uncertain depth and importance and may
in fact be best used as fuel.
Number of species

Undiscovered and discovered
species
According to the
Global
Taxonomy Initiative and the
European Distributed
Institute of Taxonomy, the
total number of species for
some phyla may be much higher as what we know currently:
- 10–30 million insects; (of some 0,9 we
know today )
- 5–10 million bacteria;
- 1.5 million fungi; (of some 0,4 million we
know today )
- ~1 million mites
Due to the fact that we know but a portion of the organisms in the
biosphere, we do not have a complete understanding of the workings
of our environment. To make matters worse, according to professor
James Mallet, we are wiping out these species against an
unprecedented rate. This means that even before a new species has
had the chance of being studied and classified, it may already be
extinct.
Threats
During the last century, erosion of biodiversity has been
increasingly observed. Studies show that 30% of all natural species
will be extinct by 2050. Of these, about one eighth of the known
plant species are threatened with
extinction. Some estimates put the loss at up to
140,000 species per year (based on
Species-area theory) and subject to
discussion. This figure indicates
unsustainable ecological practices, because
only a small number of species come into being each year. Almost
all scientists acknowledge that the rate of species loss is greater
now than at any time in human history, with extinctions occurring
at rates hundreds of times higher than
background extinction rates.
The factors that threaten biodiversity have been variously
categorized. Jared Diamond describes an "Evil Quartet" of habitat
destruction, overkill, introduced species, and secondary
extensions.
Edward O. Wilson prefers the
acronym HIPPO, standing for
Habitat destruction,
Invasive
species,
Pollution, Human
Over
Population, and
Overharvesting. The most authoritative
classification in use today is that of
IUCN’s
Classification of Direct Threats adopted by most major
international conservation organizations such as the US Nature
Conservancy, the World Wildlife Fund, Conservation International,
and Birdlife International.
Destruction of habitat
Most of the species extinctions from 1000 AD to 2000 AD are due to
human activities, in particular destruction of plant and animal
habitats. Raised rates of
extinction are being driven by human
consumption of organic resources, especially
related to
tropical forest
destruction. While most of the species that are becoming extinct
are not food species, their
biomass is converted into human food when
their habitat is transformed into
pasture,
cropland, and
orchards. It is estimated that more than a third of
the Earth's biomass is tied up in only the few species that
represent
humans,
livestock and
crops.
Because an
ecosystem decreases in
stability as its species are made extinct, these studies warn that
the global ecosystem is destined for collapse if it is further
reduced in complexity. Factors contributing to loss of biodiversity
are:
overpopulation,
deforestation,
pollution (
air
pollution,
water pollution,
soil contamination) and
global warming or climate change, driven by
human activity. These factors, while all stemming from
overpopulation, produce a cumulative impact upon
biodiversity.
There are systematic relationships between the area of a habitat
and the number of species it can support, with greater sensitivity
to reduction in habitat area for species of larger body size and
for those living at lower latitudes or in forests or oceans. Some
characterize loss of biodiversity not as ecosystem degradation but
by conversion to trivial standardized ecosystems (e.g.,
monoculture following
deforestation). In some countries lack of
property rights or access regulation to biotic resources
necessarily leads to biodiversity loss (degradation costs having to
be supported by the community).
A September 14, 2007 study conducted by the
National Science Foundation
found that biodiversity and
genetic
diversity are dependent upon each other—that diversity within a
species is necessary to maintain diversity among species, and vice
versa. According to the lead researcher in the study, Dr. Richard
Lankau, "If any one type is removed from the system, the cycle can
break down, and the community becomes dominated by a single
species."
At present, the most threathened ecosystems are those found in
fresh water. The marking of fresh water
ecosystems as the ecosystems most under threat was done by the
Millennium Ecosystem
Assessment 2005, and was confirmed again by the project
"
Freshwater Animal Diversity Assessment",
organised by the
biodiversity platform, and the
French
Institut de
recherche pour le développement (MNHNP).
Exotic species
The rich diversity of unique species across many parts of the world
exist only because they are separated by barriers, particularly
large rivers, seas, oceans, mountains and deserts from other
species of other land masses, particularly the highly fecund,
ultra-competitive, generalist "super-species". These are barriers
that couldn't have been easily crossed by natural processes, except
through
continental drift.
However, humans have invented transportation with the ability to
bring into contact species that they've never met in their
evolutionary history; also, this is done on a time scale of days,
unlike the centuries that historically have accompanied major
animal migrations. As these species that never met before come in
contact with each other, the rate at which species are extincting
is increasing still. See below for an example.
The widespread introduction of
exotic
species by humans is a potent threat to biodiversity. When
exotic species are introduced to ecosystems and establish
self-sustaining populations, the endemic species in that ecosystem
that have not evolved to cope with the exotic species may not
survive. The exotic organisms may be either
predators,
parasites, or
simply aggressive species that deprive indigenous species of
nutrients, water and light. These
invasive species often have features, due
to their evolutionary background and new environment, that make
them highly competitive; able to become well-established and spread
quickly, reducing the effective habitat of
endemic species.
Exotic species are introduced by human, either unwillingly or
intentionally. Examples on unwilling introduction are fore example
ladybugs, ... These were bred to help in combating pests in
agriculture (for greenhouses). Other examples of unwilling
introduction are species that are unknowingly brought in by vessel
or automotive. These include eg certain bacteria, spiders, seeds of
certain plants, ... Examples of intentional introduction are the
planting of exotic plants in gardens. It is clear that with simple
measures the preventing of the spread of exotic plants, yet as of
present, trying to reduce the inflow of exotic species has remained
low on the political agenda. Also, the intentional planting of
species that are marked as "indiginous", yet are from a
non-indigenous strain can be considered exotic and create problems
in the ecosystem. For example in Belgium, Prunus spinosa (an
indigenous species) that originates from Eastern Europe has been
introduced. This has created problems, as the this tree species
comes into leave much sooner than their West European counterparts,
bringing the Thecla betulae butterfly (which feed on the leaves)
into trouble.
As a consequence of the above, if humans continue to combine
species from different ecoregions, there is the potential that the
world's ecosystems will end up dominated by relatively a few,
aggressive,
cosmopolitan
"super-species".
At present, several countries have already imported so much exotic
species, that the own indigenous fauna/flora is greatly
outnumbered. For example, in Belgium, only 5% of the indigenous
trees remain.
In 2004, an international team of scientists estimated that 10
percent of species would become extinct by 2050 because of global
warming. “We need to limit climate change or we wind up with a lot
of species in trouble, possibly extinct,” said Dr. Lee Hannah, a
co-author of the paper and chief climate change biologist at the
Center for Applied Biodiversity Science at Conservation
International.
Genetic pollution
Purebred naturally evolved region specific wild
species can be threatened with
extinction through the process of
genetic pollution i.e. uncontrolled
hybridization,
introgression and genetic swamping which leads
to homogenization or replacement of local
genotypes as a result of either a numerical and/or
fitness advantage of introduced
plant or animal. Nonnative species can bring about a form of
extinction of native plants and animals by hybridization and
introgression either through purposeful introduction by humans or
through habitat modification, bringing previously isolated species
into contact. These phenomena can be especially detrimental for
rare species coming into contact with more abundant ones. The
abundant species can interbreed with the rarer, swamping the entire
gene pool and creating hybrids, thus driving the entire native
stock to complete extinction. Attention has to be focused on the
extent of this under appreciated problem that is not always
apparent from
morphological
(outward appearance) observations alone. Some degree of
gene flow may be a normal, evolutionarily
constructive, process, and all constellations of
genes and
genotypes cannot be
preserved. However, hybridization with or without introgression
may, nevertheless, threaten a rare species' existence.
Hybridization and genetics
In
agriculture and
animal husbandry, the
green revolution popularized the use of
conventional
hybrid to increase
yield by creating "
high-yielding
varieties". Often the handful of hybridized breeds originated
in developed countries and were further hybridized with local
varieties in the rest of the developing world to create high yield
strains resistant to local climate and diseases. Local governments
and industry have been pushing hybridization which has resulted in
several of the indigenous breeds becoming extinct or threatened.
Disuse because of unprofitability and uncontrolled intentional and
unintentional cross-pollination and crossbreeding (
genetic pollution), formerly huge gene
pools of various wild and indigenous breeds have collapsed causing
widespread
genetic erosion and
genetic pollution. This has resulted in loss of
genetic diversity and biodiversity as a
whole.
A
genetically modified
organism (GMO) is an
organism whose
genetic material has been
altered using the
genetic engineering techniques generally
known as
recombinant DNA
technology. Genetically Modified (GM) crops today have become a
common source for genetic pollution, not only of wild varieties but
also of other domesticated varieties derived from relatively
natural hybridization.
Genetic erosion coupled with genetic pollution may be destroying
unique genotypes, thereby creating a hidden crisis which could
result in a severe threat to our
food
security. Diverse genetic material could cease to exist which
would impact our ability to further hybridize food crops and
livestock against more resistant diseases and climatic
changes.
Climate Change
The recent phenomenon of
global
warming is also considered to be a major threat to global
biodiversity. For example coral reefs -which are biodiversity
hotspots- will be lost in 20 to 40 years if global warming
continues at the current trend.
Conserving biodiversity

A schematic image illustrating the
relationship between biodiversity, ecosystem services, human
well-being, and poverty.
The illustration shows where conservation action, strategies
and plans can influence the drivers of the current biodiversity
crisis at local, regional, to global scales.
Conservation biology matured in
the mid-
20th century as
ecologists,
naturalists, and other
scientists began to collectively research and
address issues pertaining to global declines in biodiversity. The
conservation ethic differs from the preservationist ethic,
historically lead by
John Muir, who
advocate for protected areas devoid of human exploitation or
interference for profit. The conservation ethic advocates for wise
stewardship and management of
natural
resource production for the purpose of protecting and
sustaining biodiversity in
species,
ecosystems, the
evolutionary
process, and human culture and society. Conservation biologists
are concerned with the trends in biodiversity being reported in
this
era, which has been labeled by science as
the
Holocene extinction period,
also known as the sixth mass extinction. Rates of decline in
biodiversity in this sixth mass extinction exceeds the five
previous
extinction spasms recorded
in the
fossil record. In response to
the extinction crisis, the research of conservation biologists is
being organized into strategic plans that include principles,
guidelines, and tools for the purpose of protecting biodiversity.
Conservation biology is a crisis orientated discipline and it is
multi-disciplinary, including ecological, social, education, and
other scientific disciplines outside of biology. Conservation
biologists work in both the field and office, in government,
universities, non-profit organizations and in industry. The
conservation of biological
diversity is a global priority in strategic conservation plans
that are designed to engage public policy and concerns affecting
local, regional and global scales of communities, ecosystems, and
cultures. Conserving biodiversity and action plans identify ways of
sustaining
human
well-being and
global economics,
including
natural capital,
market capital, and
ecosystem services.
Means
One of the strategies involves placing a monetary value on
biodiversity through
biodiversity
banking, of which one example is the Australian
Native Vegetation
Management Framework. Other approaches are the creation of
gene banks, as well as the creation of
gene banks that have the intention of
growing the indigenous species for reintroduction to the ecosystem
(eg via tree nurseries, ...) The eradication of exotic species is
also an important method to preserve the local biodiversity. Exotic
species that have become a pest can be identified using taxonomy
(eg with
DAISY,
barcode of life, ...) and
can then be eradicated. This method however can only be used
against a large group of a certain exotic organism due to the
econimic cost. Other measures contributing to the preservation of
biodiversity include: the reduction of pesticide use and/or a
switching to organic pesticides, ... These measures however, are of
less importance than the preserving of rural lands, reintroduction
of indigenous species and the removal of exotic species. Finally,
if the continued preservation of native organisms in an area can be
guaranteed, efforts can be made in trying to reintroduce eliminated
native species back into the environment. This can be done by first
determining which species were indiginous to the area, and then
reintroducing them. This determination can be done using databases
as the
Encyclopedia_of_life,
Global
Biodiversity Information Facility, ... Extermination is usually
done with either (ecological) pesticides, or natural
predators.
Strategies
As noted above (Distribution), biodiversity is not as rich
everywhere on the planet. Regions as the tropics and subtropics are
considerably much richer in biodiversity than regions in temperate
climates. In addition, in temperate climates, allot of countries
are located which are already vastly urbanised, and require -in
addition- great amounts of space for the growing of crops. As
rehabilitating the biodiversity within these countries would again
require the clearing and redeveloping of spaces, it has been
proposed of some that efforts are best instead directed unto the
tropics. Arguments include economics, it would be far less costly
and more efficient to preserve the biodiversity in the tropics,
especially as many countries in these areas are only now beginning
to urbanise.
However, only directing the efforts into these areas would not be
enough, as many species still need to migrate at certain times of
the year, requiring a connection to other regions/countries. In the
more urbanised countries in temperate climates, this would mean
that
wildlife corridors need to be
made. However, making wildlife corridors would still be
considerably cheaper and easier than clearing/preserving entirely
new areas.
Judicial status
Biodiversity is beginning to be evaluated and its evolution
analysed (through observations, inventories, conservation...) as
well as being taken into account in political and judicial
decisions:
- The relationship between law and ecosystems is very ancient and
has consequences for biodiversity. It is related to property
rights, both private and public. It can define protection for
threatened ecosystems, but also some rights and duties (for
example, fishing rights, hunting
rights).
- Law regarding species is a more recent issue. It defines
species that must be protected because they may be threatened by
extinction. The U.S. Endangered
Species Act is an example of an attempt to address the "law and
species" issue.
- Laws regarding gene pools are only about a century old . While
the genetic approach is not new (domestication, plant traditional
selection methods), progress made in the genetic field in the past
20 years have led to a tightening of laws in this field. With the
new technologies of genetic analysis and genetic engineering, people are going
through gene patenting, processes patenting,
and a totally new concept of genetic resources. A very hot debate
today seeks to define whether the resource is the gene, the
organism itself, or its DNA.
The 1972
UNESCO
World Heritage convention established that
biological resources, such as plants, were the common heritage of
mankind. These rules probably inspired the creation of
great public banks of genetic resources, located outside the
source-countries.
New global agreements (e.g.
Convention on Biological
Diversity), now give
sovereign national rights over
biological resources (not property). The idea of static
conservation of biodiversity is disappearing and being replaced by
the idea of dynamic conservation, through the notion of resource
and innovation.
The new agreements commit countries to
conserve
biodiversity,
develop resources for
sustainability and
share the benefits
resulting from their use. Under new rules, it is expected that
bioprospecting or collection of
natural products has to be allowed by the biodiversity-rich
country, in exchange for a share of the benefits.
Sovereignty principles can rely upon what is better known as
Access and Benefit Sharing Agreements (ABAs). The
Convention on
Biodiversity spirit implies a prior
informed consent between the source country
and the collector, to establish which resource will be used and for
what, and to settle on a
fair agreement on benefit sharing. Bioprospecting can become a
type of
biopiracy when those principles
are not respected.
Uniform approval for use of biodiversity as a legal standard has
not been achieved, however. At least one legal commentator has
argued that biodiversity should not be used as a legal standard,
arguing that the multiple layers of scientific uncertainty inherent
in the concept of biodiversity will cause administrative waste and
increase litigation without promoting preservation goals. See
Fred Bosselman, A Dozen Biodiversity Puzzles, 12
N.Y.U. Environmental Law Journal 364 (2004)
Analytical limits
Taxonomic and size bias
Less than 1% of all species that have been described have been
studied beyond simply noting its existence. Biodiversity researcher
Sean Nee points out that the vast majority of Earth's biodiversity
is microbial, and that contemporary biodiversity physics is "firmly
fixated on the visible world" (Nee uses "visible" as a synonym for
macroscopic). For example, microbial life is very much more
metabolically and environmentally diverse than multicellular life
(see
extremophile). Nee has stated: "On
the tree of life, based on analyses of small-subunit
ribosomal RNA, visible life consists of barely
noticeable twigs.
The size bias is not restricted to consideration of microbes.
Entomologist Nigel Stork states that "to a first approximation, all
multicellular species on Earth are insects". Even in insects,
however, the extinction rate is high and indicative of the general
trend of the sixth greatest extinction period that human society is
faced with. Moreover, there are species co-extinctions, such as
plants and beetles, where the extinction or decline in one is
reciprocated in the other.
Definition
- Biodiversity is the variety of life: the different plants,
animals and micro-organisms, their genes and the ecosystems of
which they are a part. It is home to more than one million species
of plants and animals, many of which are found nowhere else in the
world.
- “Biodiversity” is often defined as the variety of all forms of
life, from genes to species, through to the broad scale of
ecosystems (for a list of variants on this simple definition see
Gaston 1996). "
See also
References
Further reading
- Leveque, C. & J. Mounolou (2003) Biodiversity. New
York: John Wiley. ISBN 0470849576
- Margulis, L., Dolan, Delisle, K.,
Lyons, C. Diversity of Life: The Illustrated Guide to the Five
Kingdoms. Sudbury: Jones & Bartlett Publishers. ISBN
0763708623
- Alexander V. Markov, and Andrey V. Korotayev (2007) "Phanerozoic marine biodiversity
follows a hyperbolic trend" Palaeoworld 16(4): pp.
311–318.
- Moustakas, A. & I. Karakassis (in press). A geographic analysis of the published aquatic
biodiversity research in relation to the ecological footprint of
the country where the work was done. Stochastic Environmental Research and Risk
Assessment, Doi: 10.1007/s00477-008-0254-2.
- Novacek, M. J. (ed.) (2001) The Biodiversity Crisis: Losing
What Counts. New York: American Museum of Natural History
Books. ISBN 1565845706
External links
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