Biodiversity
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.Biodiversity is a
neologism and a portmanteau word, from biology and diversity. The Science Division of The
Nature Conservancy used the term natural diversity in a 1975 study, The Preservation of Natural
Diversity. The term biological diversity was used even before that by conservation scientists like
Robert E. Jenkins and Thomas Lovejoy. The word biodiversity itself 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.The word
biodiversity was deemed more effective in terms of communication than biological diversity.Since
1986 the terms and the concept have achieved widespread use among biologists,
environmentalists, political leaders, and concerned citizens worldwide. It is generally 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.The term natural heritage predates biodiversity, though it is a less scientific term and
more easily comprehended in some ways by the wider audience interested in conservation.
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 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.
Biological Organization
The most straightforward definition is variation of life at all levels of biological organization.A
second definition holds that biodiversity is a measure of the relative diversity among organisms
present in different ecosystems. Diversity in this definition includes diversity within a species and
among species, and comparative diversity among ecosystems.A third definition that is often used
by ecologists is 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 biodiversity has been identified.Genetic diversity diversity of
genes within a species. There is a genetic variability among the populations and the individuals of
the same species. See also population genetics.Species diversity diversity among species in an
ecosystem. Biodiversity hotspots are excellent examples of species diversity.Ecosystem diversity
diversity at a higher level of organization, the ecosystem. To do with the variety of ecosystems on
Earth.This third definition, which conforms to the traditional five organization layers in biology,
provides additional justification for multilevel approaches.
The 1992 United Nations Earth Summit in Rio de Janeiro defined biodiversity 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.If the gene is the fundamental unit of natural selection,
according to E. O. Wilson, the real biodiversity is genetic diversity. 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.For ecologists,
biodiversity is also the diversity of durable interactions among species. It not only applies to
species, but also to their immediate environment biotope and their larger ecoregion. In each
ecosystem, living organisms are part of a whole, interacting with not only other organisms, but
also with the air, water, and soil that surround them.
Measurement Of Biodiversity
It has been suggested that some content from this article be split into a separate article entitled
Measurement of biodiversity.Biodiversity is a broad concept, so 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, this measure should quantify
a value that is broadly shared among locally affected people. For others, a more economically
defensible definition should allow the ensuring of continued possibilities for both adaptation and
future use by people, assuring environmental sustainability.As a consequence, biologists argue
that this measure is likely to be associated with the variety of genes. Since it cannot always be
said which genes are more likely to prove beneficial, the best choice for conservation is to assure
the persistence of as many genes as possible. For ecologists, this latter approach is sometimes
considered too restrictive, as it prohibits ecological succession.Biodiversity is usually plotted as
taxonomic richness of a geographic area, with some reference to a temporal scale. Whittaker
described three common metrics used to measure specieslevel biodiversity, encompassing
attention to species richness or species evenness
There are three other indices which are used by ecologists,Alpha diversity refers to diversity
within a particular area, community or ecosystem, and is measured by counting the number of
taxa within the ecosystem usually species.Beta diversity is species diversity between ecosystems
this involves comparing the number of taxa that are unique to each of the ecosystems.Gamma
diversity is a measure of the overall diversity for different ecosystems within a region.Biodiversity
is not distributed evenly on Earth. It is consistently richer in the tropics and in other localized
regions such as the California 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 are formally classified as
rare or endangered or threatened species moreover, most scientists estimate 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.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.Hotspots unfortunately tend to
occur near areas of dense human habitation, leading to threats to their many endemic species.
Global Macroscopic Species
Biodiversity found on Earth today is the result of 4 billion years of evolution. The origin of life is
not well known to science, though limited evidence suggests that life may already have been
wellestablished a few 100 million years after the formation of the Earth. Until approximately 600
million years ago, all life consisted of bacteria and similar singlecelled 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 10 million.
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. At present, the number of species estimated to have gone extinct as
a result of human action is still far smaller than are observed during the major mass extinctions of
the geological past. However, it has been argued that the present rate of extinction is sufficient to
create a major mass extinction in less than 100 years. Others dispute this and suggest that the
present rate of extinctions could be sustained for many thousands of years before the loss of
biodiversity matches the more than 20% losses seen in past global extinction events.New species
are regularly discovered on average about three new species of birds each year and many,
though discovered, are not yet classified an estimate states that about 40% of freshwater fish
from South America are not yet classified. Most of the terrestrial diversity is found in tropical
forests.
Biological Sources
A significant proportion of drugs are derived, directly or indirectly, from biological sources in most
cases these medicines can not presently be synthesized in a laboratory setting. About 40% of the
pharmaceuticals used in the US are manufactured using natural compounds found in plants,
animals, and microorganisms. Moreover, only a small proportion of the total diversity of plants
has been thoroughly investigated for potential sources of new drugs. Many drugs are also derived
from microorganisms.A wide range of industrial materials are derived directly from biological
resources. These include building materials, fibers, dyes, resins, gums, adhesives, rubber and oil.
There is enormous potential for further research into sustainably utilizing materials from a wider
diversity of organisms.Through the field of bionics, a lot of technological advancement has been
done which may not have been the case without a rich biodiversity.For certain economical crops
e.g. foodcrops, wild varieties of the domesticated species can be reintroduced to form a better
variety than the previous domesticated species.Monoculture, the lack of biodiversity, was a
contributing factor to several agricultural disasters in history, including the Irish Potato Famine,
the European wine industry collapse in the late 1800s, and the US Southern Corn Leaf Blight
epidemic of 1970.Agricultural biodiversityHigher biodiversity also controls the spread of certain
diseases as e.g. viruses will need adapt itself with every new 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 vast untapped potential for
increasing the range of food products suitable for human consumption, provided that the high
present extinction rate can be stopped. The economic impact is gigantic, for even crops as
common as the potato which was bred through only one variety, brought back from the Inca, a lot
more can come from these species. Wild varieties of the potato will all suffer enormously through
the effects of climate change. A report by the Consultative Group on International Agricultural
Research CGIAR describes the huge economic loss. Rice, which has been improved for
thousands of years by humans, can through the same process regain some of its nutritional value
that has been lost since a project is already being carried out to do just this.
Natural History Programs
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
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 humanmade construction, and that activity alone represents
tens of billions of dollars in ecosystem services per annum to humankind.Many people derive
value from biodiversity through leisure activities such as enjoying a walk in the countryside,
birdwatching or natural history programs on television.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.There are also many
impracticallities in saving all the species currently on earth.Humans have always expanded and
developed their territory throughout history. An active approach is the only way to hault the
expansion but this often requires public funds. Currently the United States Environmental
Protection Agency has an annual budget of $7.3 billion 2007.
Many times natural resources cannot be exploited due to environmental protection acts. Fine
woods from South America and oil from Alaska are prime examples.Biodiverstiy is most closely
known to the public as a loss of animals with a backbone when in fact there exist 20 times that
number of insects 5 times as many flowering plants. As a result of the pressures of the rapidly
growing human population, human activity in many of these areas is increasing dramatically. Most
of these hotspots are located in the tropics and most of them are forests.For example, Brazil's
Atlantic Forest 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 than 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 and the alvar regions such as the Stora Alvaret on
Oland, Sweden host a large diversity of plants and animals, many of which are not found
elsewhere.While a few of these species may be highly valuable to the human race fot the above
reasons, the vast majority hold no importance and are often completely unknown to anyone but
specialists. In fact it is often estimated that less than half and perhaps less than twothirds of earth
organisms have even been identified.
Scientists Acknowledge
During the last century, erosion of biodiversity has been increasingly observed. Some studies
show that about one of eight known plant species is threatened with extinction. Some estimates
put the loss at up to 140,000 species per year based on Speciesarea 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.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 40% 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.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 otherthat diversity within a species is necessary to maintain diversity
among species, and vice versa. According to the lead researcher in the study, Dr. Richard
Lankauof, If any one type is removed from the system, the cycle can break down, and the
community becomes dominated by a single species.
Evolutionary Background
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, ultracompetitive, generalist
superspecies. These are barriers that could never be crossed by natural processes, except for
many millions of years in the future through continental drift. However humans have invented
ships and airplanes, and now have the power to bring into contact species that never have met in
their evolutionary history, and on a time scale of days, unlike the centuries that historically have
accompanied major animal migrations.
The widespread introduction of exotic species by humans is a potent threat to biodiversity. When
exotic species are introduced to ecosystems and establish selfsustaining 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 exotic or invasive
species often have features, due to their evolutionary background and new environment, that
make them highly competitive able to become wellestablished and spread quickly, reducing the
effective habitat of endemic species.
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 superspecies.Declines in amphibian populations have been
observed since 1980s. Because of the sensitivity of these organisms, they are regarded by many
scientists as a marker for the overall health of an ecosystem. Their decline has led to concern
about the general current state of biodiversity.
Hybridization And Genetics
Purebred naturally evolved region specific wild species can be threatened with extinction in a big
way 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 where the abundant ones can interbreed
with them swamping the entire rarer gene pool creating hybrids thus driving the entire original
purebred 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.In
agriculture and animal husbandry, green revolution popularized the use of conventional
hybridization to increase yield many folds by creating highyielding varieties. Often the handful of
breeds of plants and animals hybridized 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 since have been pushing
hybridization with such zeal that several of the wild and indigenous breeds evolved locally over
thousands of years having high resistance to local extremes in climate and immunity to diseases
etc. have already become extinct or are in grave danger of becoming so in the near future. Due to
complete disuse because of unprofitability and uncontrolled intentional, compounded with
unintentional crosspollination and crossbreeding genetic pollution formerly huge gene pools of
various wild and indigenous breeds have collapsed causing widespread genetic erosion and
genetic pollution resulting in great loss in 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.It is
being said that genetic erosion coupled with genetic pollution is destroying that needed unique
genetic base thereby creating an unforeseen hidden crisis which will result in a severe threat to
our food security for the future when diverse genetic material will cease to exist to be able to
further improve or hybridize weakening food crops and livestock against more resistant diseases
and climatic changes.
Conservation Biology
The conservation of biological diversity has become a global concern. Although not everybody
agrees on extent and significance of current extinction, most consider biodiversity essential.
There are basically two main types of conservation options, insitu conservation and exsitu
conservation. Insitu is usually seen as the ideal conservation strategy.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 smallsubunit 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.A reply to this, however,
is that biodiversity conservation has never focused exclusively on visible in this sense species.
From the very beginning, the classification and conservation of natural communities or
ecosystem types has been a central part of the effort. The thought behind this has been that since
invisible in this sense diversity is, due to lack of taxonomy, impossible to treat in the same
manner as visible diversity, the best that can be done is to preserve a diversity of ecosystem
types, thereby preserving as well as possible the diversity of invisible organisms.However, its
implementation is sometimes infeasible. For example, destruction of rare or endangered species'
habitats sometimes requires exsitu conservation efforts. Furthermore, exsitu conservation can
provide a backup solution to insitu conservation projects. Some believe both types of
conservation are required to ensure proper preservation. An example of an insitu conservation
effort is the settingup of protection areas. Examples of exsitu conservation efforts, by contrast,
would be planting germplasts in seedbanks, or growing the Wollemi Pine in nurseries. Such
efforts allow the preservation of large populations of plants with minimal genetic erosion.At
national levels a Biodiversity Action Plan is sometimes prepared to state the protocols necessary
to protect an individual species. Usually this plan also details extant data on the species and its
habitat. In the USA such a plan is called a Recovery Plan.The threat to biological diversity was
among the hot topics discussed at the UN World Summit for Sustainable Development, in hope of
seeing the foundation of a Global Conservation Trust to help maintain plant collections.
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.The field of biodiversity research inevitably suffers from natural human egocentric myopic
cognitive biases. It has often been criticized for being overly defined by the personal interests of
the founders i.e. terrestrial mammals giving a narrow focus, rather than extending to other areas
where it could be useful. This is termed the founder effect by Norse and Irish, 1996. This was a
play on words the founder effect in ecology typically refers to the genetic outcome when a small
population establishes an isolated breeding group.Law regarding species is a more recent issue.
It defines species that must be protected because they may be threatened by extinction. Some
people question application of these laws. 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 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 sourcecountries.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 biodiversityrich country, in exchange for a share of
the benefits.
Egocentric Myopic Cognitive Biase
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.Many believe the notion that there is 'vast
untapped potential' for reducing humankind's dependence on a relatively small number of
domesticated plant and animal species should be challenged. Jared Diamond,based on studies of
the domestication of plants and animals, argued that the rarity of species suitable for
domestication and their occurrence in just a few parts of the world, determined the limited number
of locations in which major civilizations could arise. In recent times there have been many studies
of minor food sources, but none of these sources have subsequently become major food
crops.The field of biodiversity research inevitably suffers from natural human egocentric myopic
cognitive biases. It has often been criticized for being overly defined by the personal interests of
the founders i.e. terrestrial mammals giving a narrow focus, rather than extending to other areas
where it could be useful. This is termed the founder effect by Norse and Irish, 1996. This was a
play on words the founder effect in ecology typically refers to the genetic outcome when a small
population establishes an isolated breeding group. France and Rigg reviewed the biodiversity
literature in 1998 and found that there was a significant lack of papers studying marine
ecosystems, leading them to dub marine biodiversity research the sleeping hydra. More work has
been carried out for accessible, diverse coastal systems such as coral reefs than for inaccessible,
speciespoor deep sea areas.It has been easier to mobilise public opinion and national legislation
for the terrestrial realm, which has higher visibility and falls within countries' territorial boundaries.
Marine conservation involves having to pioneer new and international mechanisms of protection
as well as solving methodological problems in marine biology relating to marine ecosystem
classification and datagathering on some of the earth's most difficult species to access and
monitor.