Biodiversity and conservation

UNIVERSITY COLLEGE OF SCIENCE, OU
Biodiversity and
Conservation
Haroon Hairan
8/1/2014

UNIT-I
Biodiversity
Biodiversity is the degree of variation of life. This can refer to genetic variation, species
variation, or ecosystem variationwithin an area, biome, or planet. Terrestrial biodiversity
tends to be highest at low latitudes near the equator, which seems to be the result of the
warm climate and high primary productivity. Marine biodiversity tends to be highest along
coasts in the Western Pacific, where sea surface temperature is highest and in mid-
latitudinal band in all oceans. Biodiversity generally tends to cluster in hotspots, and has
been increasing through time but will be likely to slow in the future.
Rapid environmental changes typically cause mass extinctions. One estimate is that <1%–
3% of the species that have existed on Earth are extant.
Since life began on Earth, five major mass extinctions and several minor events have led to
large and sudden drops in biodiversity. The Phanerozoiceon (the last 540 million years)
marked a rapid growth in biodiversity via the Cambrian explosion—a period during which
the majority of multi cellular phyla first appeared. The next 400 million years included
repeated, massive biodiversity losses classified as mass extinction events. In
the Carboniferous, rainforest collapse led to a great loss of plant and animal
life.]
The Permian–Triassic extinction event, 251 million years ago, was the worst;
vertebrate recovery took 30 million years. The most recent, the Cretaceous–Paleogene
extinction event, occurred 65 million years ago and has often attracted more attention than
others because it resulted in the extinction of the dinosaurs.
The period since the emergence of humans has displayed an ongoing biodiversity reduction
and an accompanying loss of genetic diversity. Named the Holocene extinction, the
reduction is caused primarily by human impacts, particularly habitat destruction.
Conversely, biodiversity impacts human health in a number of ways, both positively and
negatively.
The United Nations designated 2011–2020 as the United Nations Decade on Biodiversity.
Definitions
"Biodiversity" 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 presents a unified view
of the traditional three levels at which biological variety has been identified:
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species diversity
ecosystem diversity
genetic diversity
In 2003 Professor Anthony Campbell at Cardiff University, UK and the Darwin
Centre, Pembrokeshire, defined a fourth level: Molecular Diversity.
This multilevel construct is consistent with Dasmann and Lovejoy. 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. Wilcox's definition was
"Biological diversity is the variety of life forms...at all levels of biological systems (i.e.,
molecular, organismic, population, species and ecosystem)..." The 1992 United
Nations Earth Summit 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 definition is used in the United
Nations Convention on Biological Diversity.
One textbook's definition is "variation of life at all levels of biological organization".
Genetically biodiversity can be defined as the diversity of alleles, genes, and organisms.
They study processes such as mutation and gene transfer that drive evolution.
Measuring diversity at one level in a group of organisms may not precisely correspond to
diversity at other levels. However, tetrapod (terrestrial vertebrates) taxonomic and
ecological diversity shows a very close correlation
Distribution
Biodiversity is not evenly distributed, rather it varies greatly across the globe as well as
within regions. Among other factors, the diversity of all living things (biota) depends on
temperature, precipitation, altitude, soils, geography and the presence of other species. The
study of the spatial distribution of organisms, species, and ecosystems, is the science
of biogeography.
Diversity consistently measures higher in the tropics and in other localized regions such as
the Cape Floristic Region and lower in polar region generally. Rain forests that have had
wet climates for a long time, such as Yasuni National Park in Ecuador, have particularly
high biodiversity.
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Terrestrial biodiversity is up to 25 times greater than ocean biodiversity. Although a recent
discovered method put the total number of species on Earth at 8.7 million of which 2.1
million were estimated to live in the ocean, however this estimate seems to under-
represent diversity of microorganisms.
Latitudinal gradients
Generally, there is an increase in biodiversity from the poles to the tropics. Thus localities
at lower latitudes have more species than localities at higher latitudes. This is often
referred to as the latitudinal gradient in species diversity. Several ecological mechanisms
may contribute to the gradient, but the ultimate factor behind many of them is the greater
mean temperature at the equator compared to that of the poles.
Even though terrestrial biodiversity declines from the equator to the poles, some studies
claim that this characteristic is unverified in aquatic ecosystems, especially in marine
ecosystems. The latitudinal distribution of parasites does not follow this rule.
Hotspots
A biodiversity hotspot is a region with a high level of endemic species that is under threat
from humans. The term hotspot was introduced in 1988 by Dr. Sabina Virk. While hotspots
are spread all over the world, the majority are forest areas and most are located in
the tropics.
Brazil's Atlantic Forest is considered one such hotspot, containing roughly 20,000 plant
species, 1,350 vertebrates, and millions of insects, about half of which occur nowhere else.
The island of Madagascar, particularly the unique Madagascar dry deciduous forests and
lowland rainforests, possess a high ratio of endemism. Since the island separated from
mainland Africa 66 million years ago, many species and ecosystems have evolved
independently. Indonesia's 17,000 islands cover 735,355 square miles (1,904,560 km2
)
contain 10% of the world's flowering plants, 12% of mammals and 17%
of reptiles, amphibians and birds—along with nearly 240 million people. Many regions of
high biodiversity and/or endemism arise from specialized habitats which require unusual
adaptations, for example alpine environments in high mountains, or Northern
European peat bogs.
Accurately measuring differences in biodiversity can be difficult. Selection bias amongst
researchers may contribute to biased empirical research for 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.
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Evolution and History
Biodiversity is the result of 3.5 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 only 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, invertebrate diversity showed little overall trend, and vertebrate diversity shows an
overall exponential trend. This dramatic rise in diversity was marked by periodic, massive
losses of diversity classified as mass extinction events. A significant loss occurred when
rainforests collapsed in the carboniferous. The worst was the Permo-Triassic extinction,
251 million years ago. Vertebrates took 30 million years to recover from this event.
The fossil record suggests that the last few million years featured the greatest biodiversity
in history. However, not all scientists support this view, since there is uncertainty as to how
strongly the fossil record is biased by the greater availability and preservation of
recent geologic sections. Some scientists believe that corrected for sampling artifacts,
modern biodiversity may not be much different from biodiversity 300 million years
ago. Where as others consider the fossil record reasonably reflective of the diversification
of life. Estimates of the present global macroscopic species diversity vary from 2 million to
100 million, with a best estimate of somewhere near 9 million, the vast
majority arthropods. Diversity appears to increase continually in the absence of natural
selection.
Evolutionary diversification
The existence of a "global carrying capacity", limiting the amount of life that can live at
once, is debated, as is the question of whether such a limit would also cap the number of
species. While record of life in the sea shows a logistic pattern of growth, life on land
(insects, plants and tetrapods) shows an exponential rise in diversity. As one author states,
"Tetrapods have not yet invaded 64 per cent of potentially habitable modes, and it could be
that without human influence the ecological and taxonomic diversity of tetrapods would
continue to increase in an exponential fashion until most or all of the available ecospace is
filled."
On the other hand, changes through the Phanerozoic correlate much better with
the hyperbolic model (widely used in population biology,demography and macrosociology,
as well as fossil biodiversity) than with exponential and logistic models. The latter models
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imply that changes in diversity are guided by a first-order positive feedback (more
ancestors, more descendants) and/or a negative feedback arising from resource limitation.
Hyperbolic model implies a second-order positive feedback. The hyperbolic pattern of
the world population growth arises from a second-order positive feedback between the
population size and the rate of technological growth. The hyperbolic character of
biodiversity growth can be similarly accounted for by a feedback between diversity and
community structure complexity. The similarity between the curves of biodiversity and
human population probably comes from the fact that both are derived from the
interference of the hyperbolic trend with cyclical andstochastic dynamics.
Most biologists agree however that the period since human emergence is part of a new
mass extinction, named 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 and in general, land has more species than the ocean; some 8.7
million species may exists on Earth, of which some 2.1 million live in the ocean
Biodiversity and human health
Biodiversity's relevance to human health is becoming an 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.) This is because the species most likely to disappear are those that
buffer against infectious disease transmission, while surviving species tend to be the ones
that increase disease transmission, such as that of West Nile Virus, Lyme disease and
Hantavirus, according to a study done co-authored by Felicia Keesing, an ecologist at Bard
College, and Drew Harvell, associate director for Environment of the Atkinson Center for a
Sustainable Future (ACSF) at Cornell University.
The growing demand and lack of drinkable water on the planet presents an additional
challenge to the future of human health. Partly, the problem lies in the success of water
suppliers to increase supplies, and failure of groups promoting preservation of water
resources. While the distribution of clean water increases, in some parts of the world it
remains unequal. According to 2008 World Population Data Sheet, only 62% of least
developed countries are able to access clean water
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Some of the health issues influenced by biodiversity include dietary health and nutrition
security, infectious disease, medical science and medicinal resources, social and
psychological health. Biodiversity is also known to have an important role in reducing
disaster risk, and in post-disaster relief and recovery efforts.
Biodiversity provides critical support for drug discovery and the availability of medicinal
resources. A significant proportion of drugs are derived, directly or indirectly, from
biological sources: at least 50% of the pharmaceutical compounds on the US market are
derived from plants, animals, andmicro-organisms, while about 80% of the world
population depends on medicines from nature (used in either modern or traditional
medical practice) for primary healthcare. Only a tiny fraction of wild species has been
investigated for medical potential. Biodiversity has been critical to advances throughout
the field of bionics. Evidence from market analysis and biodiversity science indicates 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 favor of genomics
and synthetic chemistry, indeed claims about the value of undiscovered pharmaceuticals
may not provide enough incentive for companies in free markets to search for them
because of the high cost of development; meanwhile, natural products have a long history
of supporting significant economic and health innovation. Marine ecosystems are
particularly important, although inappropriate bioprospecting can increase biodiversity
loss, as well as violating the laws of the communities and states from which the resources
are taken.
Biodiversity, business and industry
Many industrial materials derive directly from biological sources. These include building
materials, fibers, dyes, rubber and oil. Biodiversity is also important to the security of
resources such as water, timber, paper, fiber, and food. As a result, biodiversity loss is a
significant risk factor in business development and a threat to long term economic
sustainability.
Biodiversity, leisure, cultural and aesthetic value
Biodiversity enriches leisure activities such as hiking, birdwatching or natural history
study. Biodiversity inspires musicians, painters, sculptors, writers and other artists. Many
cultures view themselves as an integral part of the natural world which requires them to
respect other living organisms.
Popular activities such as gardening, fish keeping and specimen collecting strongly depend
on biodiversity. The number of species involved in such pursuits is in the tens of thousands,
though the majority does not enter commerce.
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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. The general public
responds well to exposure to rare and unusual organisms, reflecting their inherent value.
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 of
the services they provide.
Levels of Biodiversity
Scientists speak of three levels of biodiversity: a. Species diversity b. Genetic diversity
c. Ecosystem diversity.
In effect, these levels cannot be separated. Each is important, interacting with and
influencing the others. A change at one level can cause changes at the other levels
Species Diversity
In all shape and size (tiny organisms to huge one): includes bacteria, protozoan, fungi,
flowering plants, ants, beetles, butterflies, birds, reptiles and large animals.
Each species is a group of organisms with unique characteristics. An individual of a species
can reproduce successfully, creating a viable offspring, only with another member of the
same species. Still learning how many species exist and how they relate to each other and
to their physical environment. Cannot predict the precise ripple effects that the loss of one
species will have on others and on ecosystems.
Keystone species: Plays critical role in ecosystems they inhabit Affect the abundance and
health of many other species. Their loss from ecosystems directly endangers the success of
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Biodiversity Status of the World
• Bacteria - 25,000 species
• Virus - 6,000 species
• Fungi - 70,000 species
• Plants - 320,000 species
• Invertebrates - 400,000 species (excluding insects)
• Insects > 1000,000 species (approximately 360,000 of which are beetles)
• Mammals 4,900 species
• Birds 9,800 species
• Amphibians and reptiles 13,000
• Fish 28,000 species

other species. Scientists estimate between 10 to 30 million species on Earth. Only about
1.75 million have been named and catalogued.
Most of insects, fungi and microscopic creatures remain unidentified. Their existence is a
mystery.
Genetic Diversity
Every individual inherits genes from its parents and passes on to the next generation.
Biodiversity is more than the variety of species. Genetic diversity everywhere (songs,
feather colors, taste and texture). Genetic variation is extremely important to the survival
of species. Genetic variability, responsible for these different traits, interact with local
environmental conditions to determine the extent to which populations can adapt to
environmental changes and survive exposure to new diseases.
Isolated populations in small patches of habitat cut off from the surrounding environment
tend to have less genetic variation than populations in large, intact ecosystems. Therefore,
those isolated populations are more susceptible to extinction.
Ecosystem Diversity
Populations and non-living environmental components- such as water or minerals
surrounding them interact dynamically to form an ecosystem. It includes: predators
consuming prey, pollinators selecting flowers and species responding to physical processes
such as heavy rain. Plant and Animal communities make up many kinds of ecosystems
(forest, wetlands, rangelands, mountains, deserts, terrestrial ecosystems). Species are not
evenly distributed.
UN. Biodiversity Planning Support Programme is a multi-donor initiative implemented by
the United Nations Development Programme and the United Nations Environment
Programme. Established to strengthen national capacity to prepare and implement
National Biodiversity Strategies and Action Plans (NBSAPs) in compliance with Article 6 of
the Convention.
United Nations Environment Program. World Conservation Monitoring Centre.
Biodiversity and climate change programs...
Consultative Process Towards an International Mechanism Of Scientific Expertise on
Biodiversity. Finding ways and means to put biodiversity in the priorities list of the world
issues agenda. Materials and documents on the consultative process. United Nations
Environment Program.
UNEP's Convention on Biological Diversity. Climate Change Adaptation Database.
Integrating Biodiversity into Climate Change Adaptation Planning- Guidance on the
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Integration of Biodiversity within Adaptation Planning supports Parties as they continue to
integrate climate change impacts and response activities through their implementation of
the Convention on Biological Diversity. Lots of info here.
2010 Biodiversity Indicators Partnership brings together a host of international
organizations working at the forefront of biodiversity indicator development to assess
progress towards the Convention on Biological Diversity (CBD) 2010 Target.
Millennium Ecosystem Assessment was called for by the United Nations Secretary-
General Kofi Annan in 2000, the objective of the MA was to assess the consequences of
ecosystem change for human well-being and the scientific basis for action needed to
enhance the conservation and sustainable use of those systems and their contribution to
human well-being.
Intergovernmental Science Policy Platform on Biodiversity and Ecosystem
Services (IPBES). The panel will be set up by 2011 to review research on biodiversity loss-
as an international science-policy platform to enable emerging scientific knowledge to be
translated into specific policy action at the appropriate levels. It will identify and prioritise
key scientific information for policymakers.
World Wildlife Fund Biodiversity Support Program. Promoting conservation of the
world's biological diversity. The publications on this Web site are from over a decade of
work by the Biodiversity Support Program.
Center for Biodiversity and Conservation of the American Museum of Natural History’s
mission is to mitigate critical threats to global biological and cultural diversity. Studying
biodiversity— has been a fundamental activity of the American Museum of Natural
History,in 1993, the Museum created the interdisciplinary Center for Biodiversity and
Conservation.
Biodiversity Hotspots. Conservation International's site. The science and information on
the 34 biodiversity hotspots.
Defenders of Wildlife- Biodiversity Partnership is dedicated to promoting and supporting
regional and statewide strategies to conserve biodiversity.
E. O. Wilson Biodiversity Foundation's mission is to preserve biological diversity in the
living environment by inventing and implementing business and educational strategies in
the service of conservation.
Conservation- Government/UN Sites:
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United Nations Environment Programme. World Conservation Monitoring Center.
Plant Conservation Alliance, of the Bureau of Land Management is a consortium of ten
federal government Member agencies and over 225 non-federal Cooperators representing
various disciplines within the conservation field. PCA Members and Cooperators work
collectively to solve the problems of native plant extinction and native habitat restoration,
ensuring the preservation of our ecosystem.
UN's Convention on Biological Diversity's objectives are the conservation of biological
diversity along with the sustainable use of its components while ensuring that it is used for
the benefit of all. UNEP.
Commission for Environmental Cooperation enhances collaboration among Canada,
Mexico and the United States in furthering the conservation and sustainablity of North
American biodiversity.
Conservation International. Aims to protect life on Earth and to demonstrate that human
societies will thrive when in balance with nature. Works with governments, nonprofit
organizations, universities, businesses, and local communities in priority regions to
strengthen conservation efforts.
Nature Conservancy, founded in 1951: with more than 1 million members, protected
more than 117 million acres of land and 5,000 miles of rivers worldwide — and operate
more than 100 marine conservation projects globally.
Society for Conservation Biology is an international professional organization dedicated
to promoting the scientific study of the phenomena that affect the maintenance, loss, and
restoration of biological diversity. Publishes the Conservation Biology Journal and
Conservation Magazine.
World Wildlife Fund. The largest multinational conservation organization in the world,
WWF works in 100 countries and is supported by 1.2 million members in the United States
and close to 5 million globally.
Earth Island Institute, "a non-profit, develops and supports projects that counteract
threats to the biological and cultural diversity that sustain the environment. Through
education and activism, these projects promote the conservation, preservation, and
restoration of the Earth."
Fauna & Flora International was founded in 1903, it has been instrumental in
establishing much of today’s global and local conservation infrastructure, including
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organizations such as the World Wide Fund for Nature, IUCN - The World Conservation
Union, the Convention on International Trade in Endangered Species of Wild Fauna & Flora
and conservation instruments such as the Red List of endangered species. A distinctive
feature of Fauna & Flora International is their focus on working with local communities to
help them develop the capacity to conserve their own biodiversity whilst also improving
their well being - long into the future.
CBD
The Convention on Biological Diversity (CBD), known informally as the Biodiversity
Convention, is a multilateral treaty. The Convention has three main goals:
1. conservation of biological diversity (or biodiversity);
2. sustainable use of its components; and
3. fair and equitable sharing of benefits arising from genetic resources
In other words, its objective is to develop national strategies for the conservation and
sustainable use of biological diversity. It is often seen as the key document
regardingsustainable development.
The Convention was opened for signature at the Earth Summit in Rio de Janeiro on 5 June
1992 and entered into force on 29 December 1993.
2010 was the International Year of Biodiversity. The Secretariat of the Convention on
Biological Diversity is the focal point for the International Year of Biodiversity. At the 2010
10th Conference of Parties (COP) to the Convention on Biological Diversity in October
in Nagoya, Japan, the Nagoya Protocol was adopted.[1]
On 22 December 2010, the UN
declared the period from 2011 to 2020 as the UN-Decade on Biodiversity. They, hence,
followed a recommendation of the CBD signatories during COP10 atNagoya in October
2010.
The convention recognized for the first time in international law that the conservation of
biological diversity is "a common concern of humankind" and is an integral part of the
development process. The agreement covers all ecosystems, species, and genetic resources.
It links traditional conservation efforts to the economic goal of using biological resources
sustainably. It sets principles for the fair and equitable sharing of the benefits arising from
the use of genetic resources, notably those destined for commercial use. It also covers the
rapidly expanding field of biotechnology through its Cartagena Protocol on Biosafety,
addressing technology development and transfer, benefit-sharing and biosafety issues.
Importantly, the Convention is legally binding; countries that join it ('Parties') are obliged
to implement its provisions.
The convention reminds decision-makers that natural resources are not infinite and sets
out a philosophy of sustainable use. While past conservation efforts were aimed at
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protecting particular species and habitats, the Convention recognizes that ecosystems,
species and genes must be used for the benefit of humans. However, this should be done in
a way and at a rate that does not lead to the long-term decline of biological diversity.
The convention also offers decision-makers guidance based on the precautionary
principle that where there is a threat of significant reduction or loss of biological diversity,
lack of full scientific certainty should not be used as a reason for postponing measures to
avoid or minimize such a threat. The Convention acknowledges that substantial
investments are required to conserve biological diversity. It argues, however, that
conservation will bring us significant environmental, economic and social benefits in
return.
The Convention on Biological Diversity of 2010 would ban some forms of geoengineering.
Issues under the Convention
Some of the many issues dealt with under the convention include:
• Measures and incentives for the conservation and sustainable use of biological
diversity.
• Regulated access to genetic resources and traditional knowledge, including Prior
Informed Consent of the party providing resources.
• Sharing, in a fair and equitable way, the results of research and development and the
benefits arising from the commercial and other utilization of genetic resources with the
Contracting Party providing such resources (governments and/or local communities
that provided the traditional knowledge or biodiversity resources utilized).
• Access to and transfer of technology, including biotechnology, to the governments
and/or local communities that provided traditional knowledge and/or biodiversity
resources.
• Technical and scientific cooperation.
• Coordination of a global directory of taxonomic expertise (Global Taxonomy
Initiative).
• Impact assessment.
• Education and public awareness.
• Provision of financial resources.
• National reporting on efforts to implement treaty commitments.
CITES
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CITES (the Convention on International Trade in Endangered Species of Wild Fauna
and Flora, also known as the Washington Convention) is a multilateral treaty to protect
endangered plants and animals. It was drafted as a result of a resolution adopted in 1963 at
a meeting of members of the International Union for Conservation of Nature (IUCN). The
convention was opened for signature in 1973, and CITES entered into force on 1 July 1975.
Its aim is to ensure that international trade in specimens of wild animals and plants does
not threaten the survival of the species in the wild, and it accords varying degrees of
protection to more than 35,000 speciesof animals and plants. In order to ensure that
the General Agreement on Tariffs and Trade (GATT) was not violated, the Secretariat of
GATT was consulted during the drafting process.
CITES is one of the largest and oldest conservation and sustainable use agreements in
existence. Participation is voluntary, and countries that have Funding for the activities of
the Secretariat and Conference of the Parties (CoP) meetings comes from a Trust Fund
derived from Party contributions. Trust Fund money is not available to Parties to improve
implementation or compliance. These activities, and all those outside Secretariat activities
(training, species specific programmes such as Monitoring the Illegal Killing of Elephants -
MIKE) must find external funding, mostly from donor countries and regional organizations
such as the European Union.
Although the Convention itself does not provide for arbitration or dispute in the case of
noncompliance, 36 years of CITES in practice has resulted in several strategies to deal with
infractions by Parties. The Secretariat, when informed of an infraction by a Party, will
notify all other parties. The Secretariat will give the Party time to respond to the allegations
and may provide technical assistance to prevent further infractions. Other actions the
Convention itself does not provide for but that derive from subsequent COP resolutions
may be taken against the offending Party. These include:
• Mandatory confirmation of all permits by the Secretariat
• Suspension of cooperation from the Secretariat
• A formal warning
• A visit by the Secretariat to verify capacity
• Recommendations to all Parties to suspend CITES related trade with the offending
party
• Dictation of corrective measures to be taken by the offending Party before the
Secretariat will resume cooperation or recommend resumption of trade
Bilateral sanctions have been imposed on the basis of national legislation (e.g. the USA used
certification under the Pelly Amendment to get Japan to revoke its reservation to hawksbill
turtle products in 1991, thus reducing the volume of its exports).
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Infractions may include negligence with respect to permit issuing, excessive trade, lax
enforcement, and failing to produce annual reports (the most common).
Originally, CITES addressed depletion resulting from demand for luxury goods such as furs
in Western countries, but with the rising wealth of Asia, particularly in China, the focus
changed to products demanded there, particularly those used for luxury goods such as
ivory or shark fins or for superstitious purposes such as rhinoceros horn. As of 2013 the
demand was massive and had expanded to include thousands of species previously
considered unremarkable and in no danger of extinction such as manta rays or pangolins
IUCN
The International Union for Conservation of Nature (IUCN; in French: Union
internationale pour la conservation de la nature, UICN) is an international
organizationdedicated to finding "pragmatic solutions to our most pressing environment
and development challenges".[1]
The organization publishes the IUCN Red List of
Threatened Species, which assesses the conservation status of species.
IUCN supports scientific research, manages field projects globally and brings governments,
non-government organizations, United Nations agencies, companies and local communities
together to develop and implement policy. IUCN is the world's oldest and largest global
environmental network—a democratic membership union with more than 1,000
government and NGO member organizations, and almost 11,000 volunteer scientists in
more than 160 countries. IUCN's work is supported by more than 1,000 professional staff
in 60 offices and hundreds of partners in public, NGO and private sectors around the world.
The Union's headquarters are located in Gland, Switzerland, near Geneva.
IUCN's stated vision is "a just world that values and conserves nature". Its mission is to
"influence, encourage and assist societies throughout the world to conserve nature and to
ensure that any use of natural resources is equitable and ecologically sustainable"
History
IUCN began when the first Director General of UNESCO, Sir Julian Huxley, sponsored a
congress to establish a new environmental institution to help serve this purpose.
At that first congress (held at Fontainebleau, France), on 5 October 1948, 18 governments,
7 international organizations, and 107 national nature conservation organizations all
agreed to form the institution and signed a "constitutive act" creating an International
Union for the Protection of Nature.
From this beginning, the overriding strategy and policy of the institution has been to
explore and promote mutually beneficial conservation arrangements that suit those
promoting development as well as assisting people and nations to better preserve
their flora and fauna.[4]
When approached in 1978 by primatologist Richard Wrangham to
contribute funds to the new Digit Fund to prevent further poaching of mountain
gorillas near Dian Fossey's Karisoke Research Station in Rwanda, the International Union
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for Conservation of Nature declined to provide funds to the cause. Instead, IUCN supported
opening the Virunga Volcanoes to tourism as a way to encourage the Rwandan government
to preserve the gorillas.
At all times, the institution (in all its forms) has heavily emphasized as a key operating
principle the strong need to cater to and address the needs of local nations, communities
and peoples, so that those nations, communities and peoples can take ownership of future,
long term conservation goals and objectives in their local areas:
“ Protected areas and threatened species could most effectively be safeguarded if
local people considered it in their own interest to do so. Working with rather than
against local people became a major working principle for IUCN. ”
IUCN's World Conservation Strategy (1980) was founded upon this kind of principle, and
clearly announced the IUCN's ambitions to more effectively enter into dialogue with the
promoters of human development. The strategy was internationally applauded by many
and served to secure IUCN funds from several donors who did not themselves feel they
could open up effective dialogue in the world's developing countries, nor that United
Nations organizations and international banks would effectively engage in such dialogue.
With the pre-eminence of the concept of sustainable development, IUCN has expanded into
many of the nations around the world, making available the services of a large pool of
mainly voluntary specialists, providing local level advice and conservation services, and
expanding its networks of Committees and regional advisory bodies into increasing
numbers of countries.
Timeline
Some key dates in the growth and development of this organization include:
• 1956: Name very soon changed from International Union for the Preservation of
Nature (IUPN) to the International Union for the Conservation of Nature and Natural
Resources (IUCN)
• 1956: IUCN creates the IYF= "International Youth Federation for the Study and
Conservation of Nature", which creates in 1983 YEE=Youth Environment Europe
• 1959: UNESCO decides to create an international list of Nature Parks and equivalent
reserves, and the United Nations Secretary General asks the IUCN to prepare this list
• 1961: After more than a decade of funding difficulties, eminent science and business
personalities (including Sir Julian Huxley) decide to set up a complementary fund
(the World Wildlife Fund) to focus on fund raising, public relations, and increasing
public support for nature conservation
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• 1969: IUCN obtains a grant from the Ford Foundation which enables it to boost,
substantially, its international secretariat.
• 1972: UNESCO adopts the Convention Concerning the Protection of World Cultural
and Natural Heritage and the IUCN is invited to provide technical evaluations and
monitoring
• 1974: IUCN is involved in obtaining the agreement of its members to sign a
Convention on International Trade in Endangered Species of Wild Fauna and Flora
(CITES), whose secretariat was originally lodged with the IUCN
• 1975: The Convention on Wetlands of International Importance (Ramsar
Convention) comes into force, and its secretariat is administered from the IUCN's
headquarters
• 1980: IUCN (together with the United Nations Environment Programme and
the World Wide Fund for Nature) collaborate with UNESCO to publish a World
Conservation Strategy
• 1982: Following IUCN preparation and efforts, the United Nations General
Assembly adopts the World Charter for Nature
• 1990: Began using the name World Conservation Union as the official name, while
continuing using IUCN as its abbreviation. This name change proved to be short-lived.
• 1993: IUCN (together with United Nations Environment Programme and the World
Wide Fund for Nature) publishes Caring for the Earth
• 2001: Establishment of the IUCN Business and Biodiversity Programme
• 2008: Stopped using World Conservation Union as its official name and reverted its
name back to International Union for Conservation of Nature
• 2008: More than 6,600 leaders from government, the public sector, non-
governmental organizations, business, UN agencies and social organizations
attended IUCN World Conservation Congress in Barcelona,
Biogeographic Classification of India
Biogeographic classification of India is the division of India according
to biogeographic characteristics. Biogeography is the study of the distribution
of species (biology), organisms, and ecosystems in geographicspace and through geological
time. The biogeographic zones of India are as follows:
1. Himalayan zone.
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2. Desert zone.
3. Semiarid zone.
4. Western ghat zone.
5. Deccan plateau zone.
6. Gangetic plain zone.
7. North east zone.
8. Coastal zone.
9. Islands present near the shore line.
10. Trans Himalyan zone.
Biogeography is the study of the biosphere and of human effects on plants and animals.
According to a recent classification done by the Wild-Life Institute of India, the country has
ten biogeographic zones:
1. Trans-Himalayan Region
The Himalayan ranges immediately north of the Great Himalayan range are called the
Trans- Himalayas. The Trans-Himalayan region with its sparse vegetation has the richest
wild sheep and goat community in the world. The snow leopard is found here, as is the
migratory black-necked crane.
2. Himalayas
The Himalayas consist of the youngest and loftiest mountain chains in the world. The
Himalayas have attained a unique personality owing to their high altitude, steep gradient
and rich temperate flora.
The forests are very dense with extensive growth of grass and evergreen tall trees. Oak,
chestnut, conifer, ash, pine, deodar are abundant in Himalayas. There is no vegetation
above the snowline. Several interesting animals live in the Himalayan ranges. Chief species
include wild sheep, mountain goats, ibex, shrew, and tapir. Panda and snow leopard are
also found here.
3. Semi-Arid Areas
Adjoining the desert are the semi-arid areas, a transitional zone between the desert and the
denser forests of the Western Ghats. The natural vegetation is thorn forest. This region is
characterized by discontinuous vegetation cover with open areas of bare soil and soil-
water deficit throughout the year.
Thorny scrubs, grasses and some bamboos are present in some regions. A few species of
xerophytic herbs and some ephemeral herbs are found in this semi-arid tract. Birds,
jackals, leopards, eagles, snakes, fox, buffaloes are found in this region.
4. Western Ghats
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The mountains along the west coast of peninsular India are the Western Ghats, which
constitute one of the unique biological regions of the world. The Western Ghats extend
from the southern tip of the peninsula (8°N) northwards about 1600 km to the mouth of
the river Tapti (21°N).
The mountains rise to average altitudes between 900 and 1500 m above sea level,
intercepting monsoon winds from the southwest and creating a rain shadow in the region
to their East.
The varied climate and diverse topography create a wide array of habitats that support
unique sets of plant and animal species. Apart from biological diversity, the region boasts of
high levels of cultural diversity, as many indigenous people inhabit its forests.
The Western Ghats are amongst the 25 biodiversity hot-spots recognized globally. These
hills are known for their high levels of endemism expressed at both higher and lower
taxonomic levels. Most of the Western Ghat endemic plants are associated with evergreen
forests.
The region also shares several plant species with Sri Lanka. The higher altitude forests
were, if at all, sparsely populated with tribal people. Rice cultivation in the fertile valley
proceeded gardens of early commercial crops like areca nut and pepper. The original
vegetation of the ill-drained valley bottoms with sluggish streams in elevations below
100m would be often a special formation, the Myristica swamp.
Expansion of traditional agriculture and the spread of particularly rubber, tea, coffee and
forest tree plantations would have wiped out large pockets of primary forests in valleys.
The Western Ghats are well known for harboring 14 endemic species of caecilians (i.e.,
legless amphibians) out of 15 recorded from the region so far.
5. North-West Desert Regions
This region consists of parts of Rajasthan, Kutch, Delhi and parts of Gujarat. The climate is
characterised by very hot and dry summer and cold winter. Rainfall is less than 70 cms. The
plants are mostly xerophytic. Babul, Kikar, wild palm grows in areas of moderate rainfall.
Indian Bustard, a highly endangered bird is found here. Camels, wild asses, foxes, and
snakes are found in hot and arid deserts.
6. Deccan Plateau
Beyond the Ghats is Deccan Plateau, a semi-arid region lying in the rain shadow of the
Western Ghats. This is the largest unit of the Peninsular Plateau of India. The highlands of
the plateau are covered with different types of forests, which provide a large variety of
forest products.
7. Gangetic Plain
In the North is the Gangetic plain extending up to the Himalayan foothills. This is the largest
unit of the Great Plain of India. Ganga is the main river after whose name this plain is
20

named. The a gradational Great Plains cover about 72.4mha area with the Ganga and the
Brahmaputra forming the main drainage axes in the major portion.
The thickness in the alluvial sediments varies considerably with its maximum in the Ganga
plains. The physiogeographic scenery varies greatly from arid and semi-arid landscapes of
the Rajasthan Plains to the humid and per-humid landscapes of the Delta and Assam valley
in the east.
Topographic uniformity, except in the arid Western Rajasthan is a common feature
throughout these plains. The plain supports some of the highest population densities
depending upon purely agro-based economy in some of these areas. The trees belonging to
these forests are teak, sal, shisham, mahua, khair etc.
8. North-East India
North-east India is one of the richest flora regions in the country. It has several species of
orchids, bamboos, ferns and other plants. Here the wild relatives of cultivated plants such
as banana, mango, citrus and pepper can be found.
9. Islands
The two groups of islands, i.e., the Arabian Sea islands and Bay Islands differ significantly in
origin and physical characteristics. The Arabian Sea Islands (Laccadive, Minicoy, etc.) are
the foundered remnants of the old land mass and subsequent coral formations. On the
other hand, the Bay Islands lay only about 220 km.
Away from the nearest point on the main land mass and extend about 590 km. With a
maximum width of 58 km the island forests of Lakshadweep in the Arabian Sea have some
of the best-preserved evergreen forests of India. Some of the islands are fringed with coral
reefs. Many of them are covered with thick forests and some are highly dissected.
10. Coasts
India has a coastline extending over 5,500 km. The Indian coasts vary in their
characteristics and structures. The west coast is narrow except around the Gulf of Canbary
and the Gulf of Kutch. In the extreme south, however, it is somewhat wider along the south
Sahyadri.
The backwaters are the characteristic features of this coast. The east coast plains, in
contrast are broader due to depositional activities of the east-flowing rivers owing to the
change in their base levels.
Extensive deltas of the Mahanadi, Godavari, Krishna and Kaveri are the characteristic
features of this coast. Mangrove vegetation is characteristic of estuarine tracts along the
coast for instance, at Ratnagiri in Maharashtra.
Larger parts of the coastal plains are covered by fertile soils on which different crops are
grown. Rice is the main crop of these areas. Coconut trees grow all along the coast.
21

THE VALUES OF BIOLOGICAL DIVERSITY
Introduction
Some will argue that conservation can and should be based on economics. One view is that
supply and demand determines resource use and prevents over-exploitation. As resources
are depleted and supply lessens, price rises. Once a resource becomes very scarce, it is no
longer profitable to harvest. The strong view is that markets prevent over-exploitation. A
less strong view is that rising prices at least give an early warning of resource depletion.
With the growing realization that species are being lost and ecosystems degraded, other
economic arguments have gained credence. One argument is that the economic value of
yet-undiscovered resources (new medicines, new foods) is the best reason to save
biodiversity. Another view is based on calculating the full value of all ecosystem goods and
services as a way to demonstrate how much actual value nature provides.
Some Weaknesses of Economic Analyses
On the other hand, an economic analysis may
fail to give sufficient weight to long-term benefits have difficulty managing common
property lack approaches for assessing the costs of damage to natural systems and
functions such as water or air pollution (externalities) lack approaches to assessing the
values of natural processes such as watershed protection or amelioration of climate
(ecosystem goods and services) ignore the aesthetic, ethical, cultural and scientific parts of
the economic equation
Classification of Values of Biological Resources
Before considering each of these, we will first examine a useful framework of different
categories of valuation of natural resources.
DIRECT VALUES
Consumptive Use Value refers to non-market value of resources such as firewood, game
meat, etc. Such resources are consumed directly, without passing through a market. They
usually are not calculated (but often can be approximated). A study in Malaysia estimated
that wild pigs harvested by hunters had a value equivalent to $100 million annually. In
Zaire, 75% of animal protein comes from wild sources. In a number of poor countries,
firewood and dung are primary energy sources. As these become scarce, women spend
most of their day simply collecting fuel wood.
Productive Use Value refers to the commercial value of products that are commercially
harvested for exchange in formal markets, such as game meat, timber, fish, ivory, medicinal
plants. They are included in national income accounts like the GNP. Estimates are usually
22

made at the production end (sale of timber by the timber harvester to the sawmill), rather
than the eventual value of the furniture and houses built from the timber. In developing
countries, the commercial value of natural resources usually is a much greater fraction of
the national economy than is the case in developed countries.
Much attention has focused recently around alternative uses of the rain forest. Usually, this
is the search for valued non-wood products that can be harvested sustainably (fruits such
as Brasil nuts, and latex from rubber-tapping).
INDIRECT VALUES
Non-consumptive Use Value refers to all of the "functions" or "services" of natural
systems, as well as scientific research, bird-watching, etc. They rarely are included in any
national accounting. Table 1 below lists some important ecosystem goods and services.
Option Value refers to the value of retaining options available for the future, such as yet-
undiscovered new crops and medicines.
Existence Value refers to the value of ethical feelings for the existence of nature. Many of
us attach value to the existence of a species or habitat that we are unlikely ever to see --
mountain gorillas, the deep rainforests of Amazonia, the highlands of Madagascar. This may
include the satisfaction of knowing that certain species exist in the wild, or an ethical
dimension of responsibility to nature, or future generations, or other peoples. WWF
receives donations of $100 million a year on this basis, and it is by no means the only or
biggest recipient of such donations.
Ecosystems Goods and Services
1. Bacteria
Cycling of nutrients and gases; Organic carbon conversion in food chains; Drugs and
antibiotics; Agriculture and biotechnology
2. Plants
Cycling of nutrients and gases (atmospheric O2, CO2); Photosynthetic energy; Water cycle,
prevention of soil erosion; Food, clothing, shelter and medicine; 50% of world's nutrition
comes from 3 plants (rice, maize, wheat); 80% from total of 20 plant species (of 250,000)
3. Animals
Soil fertility (nematodes, collembola, mites, annelids); Regulation of pest populations; Plant
pollination; Food Ecological economics attempts to compute the (non-consumptive use)
value of ecosystem goods and services. While highly speculative, estimates are trillions of
dollars. As a specific example, Pimentel and others estimate the costs of soil erosion at $44
billion annually. Loss of topsoil threatens sustainability of crop production.
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Future and Present Value
Discounting is a widely used economic tool that may act against wise use of natural
resources. It is similar to an interest rate.
Given a choice, people prefer to receive $1 today rather than $1 a year from now. Today's
dollar can buy something, or earn interest in a bank. Economists capture this time-
preference with a decision-making tool called the discount rate. It is used to determine the
present value of future costs and benefits, to help us choose among various options. But by
expressing all options in monetary units, and weighing future benefits much less heavily
than present benefits, this approach can make sustainable, long-term use of natural
resources uneconomic.
For example, if the rate of interest is 10%, one dollar one year from now is worth only 91
cents, because one can invest 91 cents today and it will be worth one dollar next year. By
the same method, one dollar ten years from now is worth 39 cents today, two decades
hence is worth 15 cents today. Any resource -- a tropical forest, the world's population of
Minke whales -- has so little discounted value that it makes better economic sense to
liquidate the resource and invest the money elsewhere -- perhaps in Amazon.com (the
book seller, not the forest).
Net Present Value is a tool for calculating the benefit-cost ratio of a long-term project, using
the discount rate to adjust for the lesser importance of both future costs and future
benefits.
Sum (Bt - Ct)
NPV = ___________
(1 + d)t
Ct = costs in year t Bt = benefits in year t d = annual discount rate ( ~ interest rate)
An example shows that as the discount rate increases, long-term returns become
unimportant relative to short-term returns.
Externalities are "hidden" costs that are not included in calculations of profitability. If a
pulp mill pollutes a river, its profitability may be substantial or non-existent depending on
whether costs of pollution abatement are excluded or included.
Common property management
Economic forces acting without restraint may result in destruction of a resource. Many
fisheries have been harvested to the point of collapse. This problem may be aggravated for
"commons" resources -- those which belong to everyone and no-one, like the fish of the
open ocean, and the climate of the earth.
Food Value
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Biodiversity provides high variety of food: crops, livestock, forestry, and fish, which are
important food source of human species. A wide range of species provides many thousands
of food products, such as, fruits,vegetables, nuts, meat, and food additives in form of food
colourings, flavourings and preseratives, through agriculture and from the harvest of
natural populations. Although about 80 percent of humans' food supply comes from just 20
kinds of plants, humans use at least 40,000 species. Many people depend on these species
for food, shelter, and clothing. Earth's surviving biodiversity provides resources for
increasing the range of food and other products suitable for human use, although the
present extinction rate shrinks that potential.
Medicinal Value
are taken.
1. Introduction
Natural products are produced by a wide range of different organisms. Microorganisms,
plants, marine species, and animals employ such compounds for several purposes such as
building blocks, coenzymes and cofactors, host-defense against microbial infection and
predators, protection of ecological niches, communication between and within species,
pigments, cellular signaling, gene expression, and homeostasis maintenance. Currently,
many key therapeutic classes of drugs in use are derived from natural products, such as the
antimalarial drug artemisinin, several anticancer agents, the lipid-lowering statins and
immunosuppressors used to prevent the rejection of tissue grafts (Harvey, 2010).
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Since ancient times, natural products represent the main source of compounds employed in
drug discovery and development. Still now, nature provides the mankind with a diversity of
small bioactive compounds, opening promising avenues for the treatment of a great variety
of diseases. Indeed, through millions of years, natural products have evolved to encompass
a broad spectrum of chemical and functional diversity that enables them to target of a
nearly limitless number of biological macromolecules in a highly selective manner. In
contrast, synthetic molecules generated by combinatorial chemistry show lower chemical
diversity and selective action than their natural counterparts. Because of these
characteristics, natural products, mostly plant secondary metabolites, have seen great
success as therapeutic agents. In fact, about 50% of the drugs introduced in the market
during the last 20 years were derived directly or indirectly from bioactive compounds.
Interestingly, of the approximately 1,200 new medicines approved by the FDA in the 25-
year period up to 2006, only around one-third of the small molecules were completely
synthetic in origin, with the remaining being natural products, direct derivatives of natural
products or synthetic compounds inspired by a natural product lead (Vuorelaa et al., 2004;
Newman & Cragg, 2009; Harvey, 2010). Besides the known diversity of bioactive
compounds, it is certain that a great number of novel nature-based molecular structural
models, with novel biological activities, remain to be discovered. It is currently estimated
that approximately 420,000 plant species exist in nature; the majority of which still
unknown (Vuorelaa et al., 2004). In addition, less than 1%of microbes known by humans
can be cultivable in laboratory conditions. In fact, the therapeutic potential of metabolism-
derived microbial products is largely not explored, besides the astonishing number of
different microorganisms that inhabit the Earth. Interestingly, despite our reduced
knowledge of the microbial diversity, more than 20,000 secondary metabolites derived
from microorganisms have already been described, while only a small percentage of these
have been carried forward as natural product drugs (Knight et al., 2003). Marine organisms
also represent a significant source of bioactive molecules, much of which in phase II, phase
III and at the commercialization stage of new drug development (Galeano et al., 2011).
According to the World Health Organization (WHO), cancer is the leading cause of death
worldwide and responsible for around 7 million deaths per year, a number estimated to
reach 11 million until 2030. However, chemotherapy, the major therapeutic approach for
cancer treatment, has to deal with important constrains such as lack of aqueous solubility
and selectivity of antineoplastic drugs and the innate or acquired emergence of multidrug
resistance by cancer cells. Consequently, there is an overwhelming demand for the
discovery of novel chemo preventive compounds and to the development of new, more
potent and effective, anticancer drugs. In this scenario, natural products represent the most
valuable source of bioactive compounds able to inhibit cancer and serve as leads and
scaffolds for the development of more efficacious drugs. Indeed, historically, natural
products have been the most significant source of drugs and drug leads. Currently, around
74% of the available anticancer compounds are natural products or natural product-
26

derived (Tan et al., 2006). With this perspective, in this chapter, we outline the historical
importance and future perspectives of terrestrial and marine-sourced anticancer agents in
oncology, and discuss the impact of novel biodiversity sources, such as venoms and toxins
from several animal species, in anticancer drug development. In addition, some general
aspects of chemical modifications done in natural products core with the aim to improve
their activity and/or effectiveness are described.
2. Plants as a valuable source of anticancer drugs
Natural products with interesting biological activities and complex chemical structures
with diverse functional groups result from the phenomenon of biodiversity, which means
the richness in variety of organisms in the ecosphere (McChesney et al., 2007). These
complex molecules evolve from a natural source of combinatorial chemistry, directed to
select specific products with biological advantage. As a consequence of this natural
selection, molecules able to interact specifically with biological targets arise, thus providing
increased survival to the organisms that generated them. From a historical point of view,
natural products have long been used as the mainstay of anticancer pharmacology. From
Podophyllum peltatum, which provided the podophyllotoxins in the early 1950s, to the
Pacific yew Taxus brevifolia, from which emerged the most significant anticancer drug
paclitaxel (Taxol® Indeed, since the development of the vinca alkaloids, vinblastine and
vincristine, and the isolation of podophyllotoxins, from which derived the semisynthetic
derivatives, etoposide and teniposide, plant-derived agents have consolidated their place in
the chemotherapy armamentarium of anticancer drugs, remaining largely prescribed today
and having decades of success in the clinical set (Cragg & Newman, 2005; Newman & Cragg,
2007; Bailly, 2009), plants have been a seemingly unimaginable source of effective new
drugs.
Drug discovery from medicinal plants is an interdisciplinary and multi-stage process
characterized by the collection and identification of plant species with known biological
activities or randomly collected for screening purposes, extract preparation and biological
screening for pharmacological properties in relevant experimental models, isolation and
characterization of active compounds, and screening assays directed toward molecular
targets (Balunas & Kinghorn, 2005). Several strategies have been used to identify new
compounds for drug discovery, of which natural products, and particularly medicinal
plants, are still considered an important source of new drugs. Moreover, compounds with
new biological activities can afford important drug leads in the development of new
generations of drugs with specific and selective activities against novel molecular targets
(Balunas & Kinghorn, 2005; Bailly, 2009). During the glory decades, several classes of
plant-derived cytotoxic drugs have entered into clinical trials and some are in clinical use,
such as camptothecin, isolated from Camptotheca acuminate, the precursor of the
topotecan and irinotecan, homoharingtonine, isolated from the Chinese tree Cephalotaxus
27

harringtonia,flavopiridol, a synthetic flavonoid structurally based in the natural product
rohitukine,isolated from Dysoxylum binectariferum, combretastatin from the South African
“bushwillow” Combretum caffrum, vinorelbine, the major semi-synthetic tubulin-binding
vinca alkaloid and the taxanes (Cragg & Newman, 2005; Bailly, 2009).The
naphthoquinones, mainly lapachol and β-lapachone, are another class of anticancer agents
that has been received most attention. While lapachol failed in clinical trials due to their
toxicity, β-lapachone provides significant activity against tumor cell lines from different
histological origins, including leukemia, breast, prostate and several multidrug resistant
(MDR) cell lines. In addition to these effects, its ability to inhibit the enzyme Cdc25, a dual-
specificity phosphatase that promotes cell cycle progression and has been postulated to be
an oncogene, renewed interest in this family of compounds (Ravelo et al., 2004; Karlsson-
Rosenthal & Millar, 2006). Sesquiterpene lactones encompass a class of terpenoids derived
mainly from Asteraceae, but also found in Umbelliferae and Magnoliaciae, which have the
ability to selectively target tumor and cancer stem cells. Artemisinin from Artemisia annua
L, thapsigargin from Thapsia (Apiaceae) and parthenolide from Tanacetum parthenum and
their synthetic derivatives are the most promising drugs of this family for cancer treatment
(Ghantous et al., 2010). Studies indicate that their selectivity against tumor cells is achieved
by different mechanisms, including modulation of specific signaling pathways, induction of
oxidative stress, and epigenetic, antiangiogenic and antimetastatic activities. For instance,
thapsigargin has been shown to inhibit the sarco/endoplasmic reticulum (ER) calcium
ATPase (SERCA) pump, thus increasing intracellular Ca2+ levels, which ultimately lead to
ER stress and cell death (Christensen et al., 2009; Winther et al., 2010).
Biodiversity and human health
Biodiversity's relevance to human health is becoming an 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.) This is because the species most likely to disappear are those that
buffer against infectious disease transmission, while surviving species tend to be the ones
that increase disease transmission, such as that of West Nile Virus, Lyme disease and
Hantavirus, according to a study done co-authored by Felicia Keesing, an ecologist at Bard
College, and Drew Harvell, associate director for Environment of the Atkinson Center for a
Sustainable Future (ACSF) at Cornell University.
The growing demand and lack of drinkable water on the planet presents an additional
challenge to the future of human health. Partly, the problem lies in the success of water
suppliers to increase supplies, and failure of groups promoting preservation of water
resources. While the distribution of clean water increases, in some parts of the world it
28

remains unequal. According to 2008 World Population Data Sheet, only 62% of least
developed countries are able to access clean water
Some of the health issues influenced by biodiversity include dietary health and nutrition
security, infectious disease, medical science and medicinal resources, social and
psychological health. Biodiversity is also known to have an important role in reducing
disaster risk, and in post-disaster relief and recovery efforts.
are taken.
Biodiversity, business and industry
Many industrial materials derive directly from biological sources. These include building
materials, fibers, dyes, rubber and oil. Biodiversity is also important to the security of
resources such as water, timber, paper, fiber, and food. As a result, biodiversity loss is a
significant risk factor in business development and a threat to long term economic
sustainability.
Biodiversity, leisure, cultural and aesthetic value
Biodiversity enriches leisure activities such as hiking, birdwatching or natural history
study. Biodiversity inspires musicians, painters, sculptors, writers and other artists. Many
cultures view themselves as an integral part of the natural world which requires them to
respect other living organisms.
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Popular activities such as gardening, fish keeping and specimen collecting strongly depend
on biodiversity. The number of species involved in such pursuits is in the tens of thousands,
though the majority does not enter commerce.
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. The general public
responds well to exposure to rare and unusual organisms, reflecting their inherent value.
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 of
the services they provide.
UNIT-II
Keystone species
A keystone species is a species that has a disproportionately large effect on
its environment relative to its abundance. Such species are described as playing a critical
role in maintaining the structure of an ecological community, affecting many
other organisms in an ecosystem and helping to determine the types and numbers of
various other species in the community.
The role that a keystone species plays in its ecosystem is analogous to the role of
a keystone in an arch. While the keystone is under the least pressure of any of the stones in
an arch, the arch still collapses without it. Similarly, an ecosystem may experience a
dramatic shift if a keystone species is removed, even though that species was a small part
of the ecosystem by measures of biomass or productivity. It became a popular concept
in conservation biology. Although the concept is valued as a descriptor for particularly
strong inter-species interactions, and it has allowed easier communication between
ecologists and conservation policy-makers, it has been criticized for oversimplifying
complex ecological systems.
History
The concept of the keystone species was introduced in 1969 by Robert T. Paine, a professor
of zoology at the University of Washington. Paine developed the concept to explain his
observations and experiments on the relationship between intertidal invertebrates. In his
1966 paper, Food Web Complexity and Species Diversity, Paine described such a system
in Makah Bay in Washington. In his follow-up 1969 paper, Paine proposed the keystone
species concept, using Pisaster ochraceus, a species of starfish, and Mytilus californianus, a
30

species of mussel, as a primary example. The concept became popular in conservation, and
was deployed in a range of contexts and mobilized to engender support for conservation.
Examples
Given that there are many historical definitions of the keystone species concept, and
without a consensus on its exact definition, a list of examples best illustrates the concept of
keystone species.
A classic keystone species is a small predator that prevents a
particular herbivorous species from eliminating dominant plant species. Since the prey
numbers are low, the keystone predator numbers can be even lower and still be effective.
Yet without the predators, the herbivorous prey would explode in numbers, wipe out the
dominant plants, and dramatically alter the character of the ecosystem. The exact scenario
changes in each example, but the central idea remains that through a chain of interactions,
a non-abundant species has an out-sized impact on ecosystem functions.
One example is the herbivourous weevil Euhrychiopsis lecontei and its suggested keystone
effects on aquatic plant species diversity by foraging on nuisance Eurasian Watermilfoil.
Predators
As was described by Dr. Robert Paine in his classic 1966 paper, some sea
stars (e.g., Pisaster ochraceus) may prey on sea urchins, mussels, and other shellfish that
have no other natural predators. If the sea star is removed from the ecosystem, the mussel
population explodes uncontrollably, driving out most other species, while the urchin
population annihilates coral reefs.
Similarly, sea otters protect kelp forests from damage by sea urchins. Kelp "roots", called
holdfasts, are merely anchors, and do not perform similar roles to the roots of terrestrial
plants, which form large networks that acquire nutrients from the soil. In the absence of
sea otters, sea urchins are released from predation pressure, increasing in abundance. Sea
urchins rapidly consume near shore kelp, severing the structures at the base. Where sea
otters are present, sea urchins tend to be small and limited to crevices. Large near shore
kelp forests proliferate and serve as important habitat for a number of other species. Kelp
also increases the productivity of the near shore ecosystem through the addition of large
quantities of secondary production.
These creatures need not be apex predators. Sea stars are prey for sharks, rays, and sea
anemones. Sea otters are prey for orca.
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The jaguar, whose numbers in Central and South America have been classified as Near
Threatened, acts as a keystone predator by its widely varied diet, helping to balance the
mammalian jungle ecosystem with its consumption of 87 different species of prey.
Mutualists
Keystone mutualists are organisms that participate in mutually beneficial interactions, the
loss of which would have a profound impact upon the ecosystem as a whole. For example,
in the Avon Wheat belt region of Western Australia, there is a period of each year
when Banksia prionotes (Acorn Banksia) is the sole source of nectar for honeyeaters, which
play an important role in pollination of numerous plant species. Therefore the loss of this
one species of tree would probably cause the honeyeater population to collapse, with
profound implications for the entire ecosystem. Another example is frugivores such as
the cassowary, which spreads the seeds of many different trees, and some will not grow
unless they have been through a cassowary.
Engineers
Although the terms 'keystone' and 'engineer' are used interchangeably, the latter is better
understood as a subset of keystone species. In North America, the prairie dog is an
ecosystem engineer. Prairie dog burrows provide the nesting areas for Mountain
Plovers and Burrowing Owls. Prairie dog tunnel systems also help channel rainwater into
the water table to prevent runoff and erosion, and can also serve to change the composition
of the soil in a region by increasing aeration and reversing soil compaction that can be a
result of cattle grazing. Prairie dogs also trim the vegetation around their colonies, perhaps
to remove any cover for predators. Even grazing species such as Plains bison, pronghorn,
and Mule deer have shown a proclivity for grazing on the same land used by prairie dogs. It
is believed that they prefer the vegetative conditions after prairie dogs have foraged
through the area.
Another well known ecosystem engineer, or keystone species, is the beaver, which
transforms its territory from a stream to a pond or swamp. Beavers affect the environment
first altering the edges of riparian areas by cutting down older trees to use for their dams.
This allows younger trees to take their place. Beaver dams alter the riparian area they are
established in. Depending on topography, soils, and many factors, these dams change the
riparian edges of streams and rivers into wetlands, meadows, or riverine forests. These
dams have shown to be beneficial to myriad species including amphibians, salmon, and
song birds.
In the African savanna, the larger herbivores, especially the elephants, shape their
environment. The elephants destroy trees, making room for the grass species. Without
these animals, much of the savannah would turn into woodland.
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Umbrella Species
Umbrella species are species selected for making conservation related decisions, typically
because protecting these species indirectly protects the many other species that make up
the ecological community of its habitat. Species conservation can be subjective because it is
hard to determine the status of many species. With millions of species of concern, the
identification of selected keystone species, flagship species or umbrella species makes
conservation decisions easier. Umbrella species can be used to help select the locations of
potential reserves, find the minimum size of these conservation areas or reserves, and to
determine the composition, structure and processes of ecosystems.
Definition
Two commonly used definitions:
• A: "A wide-ranging species whose requirements include those of many other
species"
• B: A species with large area requirements for which protection of the species offers
protection to other species that share the same habitat.
Other descriptions include:
• A: "The protection of umbrella species automatically extends protection to other
species. i.e. spotted owl and old growth trees"
• B: "Traditional umbrella species, relatively large-bodied and wide-ranging species of
higher vertebrates
Use in Land use Management
The use of umbrella species as a conservation tool is highly debated. The term was first
used by Wilcox (1984) who defined an umbrella species as one whose minimum area
requirements are at least as comprehensive of the rest of the community for which
protection is sought though the establishment and management of a protected area.
Some scientists have found that the umbrella effect provides a simpler way to manage
ecological communities. Others feel that a combination of other tools establish better land
management reserves to help protect more species than just using umbrella species alone.
Individual invertebrate species can be good umbrella species because they can protect
older, unique ecosystems. There have been cases where umbrella species have protected a
large amount of area which has been beneficial to surrounding species such as the northern
spotted owl.
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Currently research is being done on land management decisions based on using umbrella
species to protect habitat of specific species as well as other organisms in the area. Dunk,
Zielinski and Welsh (2006) reported that the reserves in Northern California (Klamath-
Siskiyou forests), set aside for the northern spotted owl, also protect mollusks and
salamanders within that habitat. According to their conclusions, the reserves set aside for
the northern spotted owl “serve as a reasonable coarse-filter umbrella species for the taxa
[they] evaluated,” which were the mollusks and salamanders.
Examples of Umbrella Species
1. Northern spotted owls and old growth forest: ex. Molluscs and salamanders are
within the protective boundaries of the northern spotted owl.
2. Bay checker spot butterfly and grasslands
3. Tigers in India and elsewhere. Project Tiger was launched to save the tiger and
thereby its habitat and other species within it.
Flagship Species
The concept of flagship species is a concept with its genesis in the field of conservation
biology. The flagship species concept holds that by raising the profile of a particular
species, it can successfully leverage more support for biodiversity conservation at large in
a particular context.
Definitions
Several definitions have been advanced for the flagship species concept although the
concept has for some time been immersed in confusion even in the academic literature.
Most of the latest definitions do however focus on the strategic and socio-economical
character of the concept, with a recent publication establishing a clear link with the
marketing field.
• “a species used as the focus of a broader conservation marketing campaign based on
its possession of one or more traits that appeal to the target audience.”
• species that have the ability to capture the imagination of the public and induce
people to support conservation action and/or to donate funds
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• popular, charismatic species that serve as symbols and rallying points to stimulate
conservation awareness and action
The term flagship is linked to the metaphor of representation. In its popular usage,
flagships are viewed as ambassadors or icons for a conservation project or movement.
However, more recently, work in the field of microbiology has started to use the concept of
flagship species is a distinct way. This work relates to the biogeography of micro-organisms
and uses particular species as indicators of endemism since "eyecatching “flagships” with
conspicuous size and/or morphology are the best distribution indicators"
Examples
Examples of flagship species include the Bengal tiger (Panthera tigris), the giant
panda (Ailuropoda melanoleuca), the Golden lion tamarin (Leontopithecus rosalia),
the African elephant (Loxodonta sp.) and Asian elephant (Elephas maximus).
Flagship species can represent an environmental feature (e.g. a species or ecosystem),
cause (e.g. climate change or ocean acidification), organization (e.g. NGO or government
department) or geographic region (e.g. state or protected area)
History
The flagship species concept appears to have become popular around the mid 1980s within
the debate on how to prioritise species for conservation. The first widely available
references to use the flagship concept applied it to both neotropical primates and African
elephants and rhinos, in the typical mammal centric approach that still dominates how the
concept is used today
The use of the concept has been largely dominated by large bodied species, especially
mammals, although species from other taxonomic groups have occasionally been used
Flagship and Conflict
A major challenge for the deployment of several flagship species in non-Western contexts is
that they may come into conflict with local communities, thereby jeopardizing well-
intended conservation actions. This has been termed 'flagship mutiny' and is exemplified
by the Asian elephant in countries where there is human-elephant conflict.
Other Types of Conservation Flagship
35

Conservation flagships can also appear at broader levels, for example as ecosystems (such
as coral reefs or rainforests or protected areas (Serengeti or Yellowstone). A number of
recent initiatives has developed new conservation flagships based on conservation values
of particular areas or species. Examples of these are the EDGE project run by the Zoological
Society of London and the Hotspots run by Conservation International.
Biodiversity loss and Humans
Current extinction rates are up to 100 times greater than natural, background extinction rates,
because of the effect of humans on other organisms and ecosystems. We impact the world around us
in many ways, some of which are more destructive than others. Here are some of the ways in which
humans are causing other life forms to go extinct:
Overfishing
Overhunting
Habitat Destruction & Conversion
Habitat destruction occurs whenever humans change a landscape and alter the ecosystem that
resides there. This occurs whenever a forest is cut down for pasture or a wetland is filled in to build a
parking lot. Tropical rainforests are at high risk for this, as they are frequently cut down to create
cropland and pasture for cattle.
Invasive Species Introductions
Introduction of invasive species can do irreparable damage to an ecosystem that is not prepared to
cope with the intruders. A foreign plant might be able to out-compete all others in a given
environment, driving out the other species and replacing them with a monoculture. Humans
introduce microbes and soil particles relatively easily and unknowingly when they travel, and we
have also introduced foreign species as pest controls at times.
Climate Change
Biodiversity is threatened by climate change largely because of loss of habitat. As sea levels and
temperatures rise, plants and animals, just like humans, will be forced to relocate, to leave the places
where they live and move into new areas. This graphic illustrates the effects of climate change on one
type of habitat, mountains, as temperature and precipitation increase:
36

See UNEP/GRID Arendal Maps and Graphics Library, Climate Change Impact on Mountain Vegetation
Zones
As the climate warms, the various habitat zones move up the mountain, and along the way species
and ecosystems are invariably lost. The most vulnerable species are those that can only survive in a
narrow zone of climate, such as within a certain temperature or precipitation range. If individuals
cannot move quickly enough to stay within their required climate zone, they will perish.
This graphic shows the numbers of threatened and endangered animal species in Africa. The group of
37

bars on the far left shows totals for all of Africa’s different categories of animals (mammals, birds,
reptiles, etc.), and the other four sets of bars are broken down by region within Africa. This shows the
current status of threatened and endangered animals in Africa; climate change will only make this
worse.
Closer to home, a March 19, 2007 article in the Washington Post described one likely effect of climate
change on a familiar bird: the Baltimore Oriole. The state bird of Maryland will likely be driven out of
that state within a century, as climate change shifts its range north and towards Philadelphia.
Ecological Extinction
Ecological extinction is defined as “the reduction of a species to such low abundance that,
although it is still present in the community, it no longer interacts significantly with other
species.”
Ecological extinction stands out because it is the interaction ecology of a species that is
important for conservation work. They state that “unless the species interacts significantly
with other species in the community (e.g. it is an important predator,
competitor, symbiont, mutualist, or prey) its loss may result in little to no adjustment to the
abundance and population structure of other species.”
This view stems from the neutral model of communities that assumes there is little to no
interaction within species unless otherwise proven.
Estes, Duggins, and Rathburn (1989) recognize two other distinct types of extinction.
Global extinction is defined as “the ubiquitous disappearance of a species."
Local extinction is characterized by “the disappearance of a species from part of its natural
range.”
Keystone Species
Robert Paine (1969) first came up with the concept of a keystone species while studying
the effects of the predatory sea star Pisaster ochraceus, on the abundance of the
herbivorous gastropod, Tegula funebralis. This study took place in the rocky
intertidal habitat off the coast of Washington; Paine removed all Pisaster in 8m x 10m plots
weekly while noting the response of Tegula for two years. He found that removing the top
predator, in this case being Pisaster, reduced species number in the treatment plots. Paine
defined the concept of a keystone species as a species that has a disproportionate effect on
the community structure of an environment in relation to its total biomass. This keystone
species effect forms the basis for the concept of ecological extinction.
Examples
Estes et al. (1978) evaluated the potential role of the sea otter as the keystone predator in
near-shore kelp forests. They compared the Rat and Near islands in the Aleutian islands to
38

test if “sea otter predation controls epibenthic invertebrate populations (specifically sea
urchins), and in turn releases the vegetation association from intense grazing”. Estes and
his colleagues found that different size structures and densities of sea urchins were
correlated with the presence of sea otter populations, and because they are the principal
prey of this keystone predator, the sea otters were most likely the main determinants of
the differences in sea urchin populations. With high sea otter densities the herbivory of sea
urchins in these kelp forests was severely limited, and this made competition between algal
species the main determinant in survival. However, when sea otters were absent, herbivory
of the sea urchins was greatly intensified to the point of decimation of the kelp forest
community. This loss of heterogeneity serves as a loss of habitat for both fish and eagle
populations that depend on the richly productive kelp forest environment. Historical over
harvesting of sea otter furs has severely restricted their once wide-ranging habitat, and
only today are scientists starting to see the implications of these local extinctions.
Conservation work needs to focus on finding the density threshold that render the sea
otters an effective population. It must then continue and artificially repopulate the
historical range of the sea otter in order to allow kelp forest communities to re-establish.
The California spiny lobster, or Panulirus interruptus, is another example of a keystone
predator that has a distinct role in maintaining species diversity in its habitat. Robles
(1987) demonstrated experimentally that the exclusion of spiny lobsters from the
intertidal zone habitats led to the competitive dominance of mussels (Mytilus edulis and M.
californianus). This results shows another example of how the ecological extinction of a
keystone predator can reduce species diversity in an ecosystem. Unfortunately, the
threshold of ecological extinction has long passed due to over fishing now that many local
extinctions of the California spiny lobster are common.
Jackson et al. (2001) took a much needed historical perspective on the role of ecological
extinction caused by overfishing of oysters in the Chesapeake Bay. Commercial oyster
fishing had not affected the bay ecosystem until mechanical dredges for harvesting were
utilized in the 1870s. The bay today is plagued by eutrophication due to algal blooms, and
the resulting water is highly hypoxic. These algal blooms have competitively excluded any
other species from surviving, including the rich diversity in faunal life that once flourished
such as dolphins, manatees, river otters, sea turtles, alligators, sharks, and rays. This
example highlights the top-down loss of diversity commercial fishing has on marine
ecosystems by removing the keystone species of the environment
Invasive Species
Novaro et al. (2000) assessed the potential ecological extinction of guanacos (Lama
guanocoe) and lesser rheas (Pterocnemia pennata) as a prey source for native omnivores
39

and predators in the Argentine Patagonia. These native species are being replaced by
introduced species such as the European rabbit, red deer, and domestic cattle; the
cumulative damage from the increased herbivory by introduced species has also served to
accelerate destruction of the already dwindling Argentine pampas and steppe habitats. This
was the first study to take into account a large number of diverse predators, ranging
from skunks to pumas, as well as conduct their survey in non-protected areas that
represent the majority of southern South America. Novaro and his colleagues found that
the entire assemblage of native carnivores relied primarily on introduced species as a prey
base. They also suggested that the lesser rhea and guanaco had already passed their
ecological effective density as a prey species, and thus were ecological extinct. It is possible
that the niches of introduced species as herbivores too closely mirrored those of the
natives, and thus competition was the primary cause of ecological extinction. The effect of
introduction of new competitors, such as the red deer and rabbit, also served to alter the
vegetation in the habitat, which could have further pronounced the intensity of
competition. Guanacos and rheas have been classified as a low risk for global extinction,
but this simplistic view of their demography doesn’t take into account that they have
already become functionally extinct in the Argentine Patagonia. Novaro and his colleagues
suggest "this loss could have strong effects on plant-animal interactions, nutrient dynamics,
and disturbance regimes ..." this is a prime example of how current conservation policy has
already failed to protect the intended species because of its lack of a functionally sound
definition for extinction.
Seed dispersal mechanisms play a fundamental role in the regeneration and continuation of
community structure, and a recent study by Christian (2001) demonstrated a shift in the
composition of the plant community in the South African shrublands following an invasion
by the Argentine ant (Linepithema humile). Ants disperse up to 30% of the flora in the
shrublands and are vital to the survival of fynbos plants because they bury the large seeds
away from the dangers of predation and fire damage. It is also crucial for seeds to be
buried, because nearly all seed germination takes place in the first season after a fire.
Argentine ants, a recent invader, do not disperse even small seeds. Christian tested
whether the invasion of the Argentine ant differentially effected small and large-seeded
fauna. He found that post-fire recruitment of large-seeded flora was reduced
disproportionately for large seeds in sites already invaded by Argentine ants. These initial
low large-seed density recruitments will eventually lead the domination of small-seeded
fauna in invaded habitats. The consequences of this change in community structure
highlight the struggle for dispersal of large-seeded flora that have potential reverberations
around the world because ants are major ecological seed dispersers throughout the globe.
Climate Change
40

Climate change has produced numerous shifts in the distributions and abundances of
species. Thomas et al. (2004) went on to assess the extinction risk due to these shifts over a
broad range of global habitats. Their predictive model using midline estimates for climate
warming over the next 50 years suggests that 15-37% of species will be “committed to
extinction” be 2050. Although the average global temperature has risen .6°C, individual
populations and habitats will only respond to their local changes in climate. Root et al.
(2002) suggests that local changes in climate may account for density changes in regions,
shifts in phenology (timing) of events, changes in morphology (biology) (such as body size),
and shifts in genetic frequencies. They found that there have been an average phenological
shift of 5.1 days earlier in the spring for a broad range of over a thousand compiled studies.
This shift was also, as predicted, more pronounced in the upper latitudes that have
concurrently had the largest shift in local average temperatures.
While the loss of habitat, loss of pollinator mutualisms, and the effect of introduced species
all have distinct pressures on native populations, these effects must be looked underneath
a synergistic and not an independent framework. Climate change has the potential to
exacerbate all of these processes. Nehring (1999) found a total of 16 non-indigenous
thermophilic phytoplankton established in habitats northwards of their normal range in
the North Sea. He likened these changes in range of more southerly phytoplankton to
climatic shifts in ocean temperature. All of these effects have additive effects to the stress
on populations within an environment, and with the additionally fragile and more complete
definition of ecological extinction must be taken into account into preventative
conservation measures
Impacts of Conservation Policy
Conservation policy has historically lagged behind current science all over the world, but at
this critical juncture politicians must make the effort to catch up before massive extinctions
occur on our planet. For example, the pinnacle of American conservation policy,
the Endangered Species Act of 1973, fails to acknowledge any benefit for protecting highly
interactive species that may help maintain overall species diversity. Policy must first assess
whether the species in question is considered highly interactive by asking the questions
“does the absence or loss of this species, either directly or indirectly, incur a loss of overall
diversity, effect the reproduction or recruitment of other species, lead to a change in
habitat structure, lead to a change in productivity or nutrient dynamics between
ecosystems, change important ecological processes, or reduce the resilience of the
ecosystem to disturbances?”. After these multitudes of questions are addressed to define an
interactive species, an ecologically effective density threshold must be estimated in order
to maintain this interaction ecology. This process holds many of the same variables
41

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