Biodiversity
Biodiversity is a reletivley new term that represents the natural diversity
that is part and parcel with our natural heritage.
It also is the subject of some of our most colouful and inspiring workshops.
"hands down"
In these workshops we explore the intricate and truely magical connection
between all living things in an eco system and the relationship of various
eco systems on our entire biosphere. We also explore the vital need to
preserve and enhance our bio diversity as part and parcel of our survival
as a species.
Here we will explore the meanings of the terms Biodiversity and Natural Heritage.
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.
We like the way Wikipedia explored the subject...
The term "natural heritage" pre-dates "biodiversity",
though it is a less scientific term and more easily comprehended in some
ways by the wider audience interested in conservation. However Bio Diversity
is more descriptive of the essence of that heritage and that is "biological
diversity". It is a good word but more importantly understanding
the concept has become vitally important in the strugle to create and
maintain a sustainable future.
The 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.
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.
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.
Distribution - 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.
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, though evidence
suggests that life may already have been well-established a few 100 million
years after the formation of the Earth. Until approximately 600 million
years ago, all life consisted of bacteria and similar single-celled organisms.
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.
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.
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.
Ours it seems is definetely in trouble.
Benefits
There are a multitude of benefits of biodiversity in the sense of one
diverse group aiding another such as:
Resistance to catastrophe -
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.
Higher biodiversity also controls
the spread of certain diseases as e.g. viruses will need adapt itself
with every new species.
Food and drink - 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.
Medicines - 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.
Industrial materials - 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.
Intellectual value - Through the field of bionics, a lot of technological
advancement has been done which may not have been the case without a rich
biodiversity.
Better crop-varieties - For
for some foodcrops and other economic crops, wild varieties of the domesticated
species can be reintroduced to form a better variety than the previous
(domesticated) species. 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).
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 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.
Leisure, cultural and aesthetic value - 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.
***
Hindrances
There are also many impracticallities in saving all the species currently
on earth:
Funds
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) [7]
Withheld resources
Many times natural resources cannot be exploited due to environmental
protection acts. Fine woods from South America and oil from Alaska are
prime examples.
Preservation of invertebrate and plant species
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. While a few of these species may be
highly valuable to the human race for the above reasons, the vast majority
are often completely unknown to anyone but specialists. In fact it is
often estimated that less than half and perhaps less than two-thirds of
earth organisms have even been identified.
Numbers of species
Insects make up the vast majority of animal species.As a soft guide, however,
the numbers of identified modern species as of 2004 can be broken down
as follows: [8]
287,655 plants, including:
15,000 mosses,
13,025 ferns,
980 gymnosperms,
199,350 dicotyledons,
59,300 monocotyledons;
74,000-120,000 fungi[10];
10,000 lichens;
1,250,000 animals, including:
1,190,200 invertebrates:
950,000 insects,
70,000 mollusks,
40,000 crustaceans,
130,200 others;
58,808 vertebrates:
29,300 fish,
5,743 amphibians,
8,240 reptiles,
10,234 birds, (9799 extant as of 2006)
5,416 mammals.
However the total number of species for some phyla may be much higher:
5-10 million bacteria[11];
1.5 million fungi[10];
Threats
During the last century, erosion of biodiversity has been increasingly
observed. Some studies show that about one eighth known plant species
is 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[citation needed 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.
Destruction of habitats
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 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 Lankauof, "If
any one type is removed from the system, the cycle can break down, and
the community becomes dominated by a single species."
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 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 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 exotic or 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.
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".
Other 'Decline in amphibian
populations'
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.
Genetic pollution
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.
Hybridization and genetics
In agriculture and animal husbandry, green revolution popularized the
use of conventional hybridization to increase yield many folds by creating
"high-yielding 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 un-profitability and uncontrolled intentional, compounded with 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 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.
Management
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, in-situ conservation and ex-situ conservation.
In-situ is usually seen as the ideal conservation strategy. However, its
implementation is sometimes infeasible. For example, destruction of rare
or endangered species' habitats sometimes requires ex-situ conservation
efforts. Furthermore, ex-situ conservation can provide a backup solution
to in-situ conservation projects. Some believe both types of conservation
are required to ensure proper preservation. An example of an in-situ conservation
effort is the setting-up of protection areas. Examples of ex-situ 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).
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[citation needed]. 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[citation needed]. 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 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)
Criticisms
Some of the biodiversity of a coral reef.
Food
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.
Founder effect
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,
species-poor 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 data-gathering on some
of the earth's most difficult species to access and monitor.
Size bias
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".
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.
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