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Biological Diversity
STATEMENT OF THE ISSUE
Biological diversity, also known as biodiversity, is
used to describe all life on the Earth. This
includes humans, all types of animals and insects,
and all plants. The term biodiversity also includes
all of the natural processes that take place on the
planet, including ecosystems and the changes
that occur in ecosystems, genetic and culturali
diversity, and most importantly, the connections between all living things on the planet.ii Only
recently have scientists started discovering the connections and relationships between species and
environments around the world. Biodiversity is not as simple as just thinking about it in one
location. For example, biodiversity can be affected in a rain forest from an event that may have
occurred half way across the world. Biodiversity can be easiest thought of like a woven rug. If you
pull on thread on the rug, it could only affect the thread itself, the thread and the surrounding
threads, or it could unravel the whole rug. This is how important certain species and environments
are to biodiversity.iii Over the years, human activities and climate change have caused a great
impact on biodiversity, even causing the extinction of hundreds and thousands of species of plants
and animals.
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HISTORY OF THE ISSUE
Beginning over 140 million years ago when
dinosaurs roamed the Earth, biodiversity has
been changing. After the last Ice Age, about 2.4
million to 10,000 years ago, the Holocene period
began. The Holocene period is the current period
of geographical time.
ICE AGE
During the last Ice Ageiv, somewhere between 2.4
million to 10,000 years ago, biodiversity was
greatly affected. Before this time, dinosaurs
Map of areas covered by glaciers during Ice Age ©CoolGeography
Ecosystem: A biological community of interacting organisms and their physical environment
Climate change: a long term change in the Earth’s weather and climate patterns; increase in temperature, decrease or
increase in rain fall, and changes in wind patterns
Extinction: The state or process of a species, family, or larger group ceasing to exist
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roamed the Earth. Many scientists are still unclear as to what caused the dinosaurs to become
extinct and what caused such a major shift in climate, but it is clear that there was a very hot
period during which the dinosaurs lived and then there was a dramatic cooling of the Earth. This
cooling of the Earth lowered the temperatures so much that many of the oceans, lakes and, other
bodies of water we see today were frozen over.
Two major events in biodiversity occurred during this time, the extinction of the dinosaurs and the
transfer of different species to different areas of the world. Not only did certain animals completely
stop to exist but certain animals adapted to stay alive during the Ice Age. New species of animals
came to be through these adaptations and lived during the Ice Age. These animals roamed from
land to land and crossed into different continents. Many scientists believe that this is how many
ancestors of certain species live where they do today.
HOLOCENE PERIOD
The Holocene period is the period of time that began 12,000 to 11,500 thousand years ago and
continues to present day. The Holocene period began when the glaciers began to retreat, or melt.
The Holocene period involves great changes to biodiversity.
To start the Holocene period was the first time that modern day humans, as we are today, lived.
Further, as humans have evolved, the Holocene period has been the only period in Earth’s time that
records have been kept of animals, plants, or people. Some researchers have nicknamed the
Holocene period The Age of Man. This period is also the only time that species have made large
contributions to changing the biodiversity of their environments. Human activities cause changes to
ecosystems and the species that live in
them. This can be done through several
ways, by changing the environment
through pollution or by using it for
resources. For example, certain species of
monkeys have become extinct because of
the deforestation that is occurring in
many rainforests.
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DISCUSSION OF THE PROBLEM
Today, the main concern is the loss of
biodiversity due to human activities.
Yearly, numbers of plant and animal
species decline. Currently, if nothing is
done to try to stop biodiversity loss,
Deforestation: the clearing of large amounts of trees in forests
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species of plants and animals will continue to become extinct at a rate 1000 times faster than the
natural rate. Over 34,000 plants and 5,200 animals face extinction based on this trend. v
Further, the biggest threat to biodiversity comes from the degradation and loss of vital ecosystems.
Forests, coral reefs, and wetlands have been shrinking rapidly due to human activities. Forests in
Europe and North America have shrunk due to deforestation at rapid rates, that even with some regrowth, would not be able to save many of the species that are on the verge of extinction in these
forests.vi
CASE STUDY: BROWN GRIZZLY BEARS
Grizzly bears in the lower, western side of North America are on the verge of extinction. The biggest
threats to the grizzly bears are humans and human settlements. Grizzly bears travel throughout
dense, mountainous, and wooded areas in search of food. Many of these areas have now been
destroyed to make room for human developments such as roads and homes.
In addition, there were no hunting regulations on grizzly bears until the 1980’s. Further, many grizzly
bears get mistaken for black bears, which are legal to hunt, and are killed accidently by campers
and hunters. Currently, there are only a little over 1,000 grizzly bears left in the lower part of North
America. Efforts are being made to try and increase the numbers of grizzly bears by scientists and
National Park groups such as the United States Forest Service.
CLIMATE CHANGE AND BIODIVERSITY
Climate change has added stress to already
wounded ecosystems and has further been a
reason for biodiversity loss. A rise in
temperature would cause the most damage to
ecosystems and the biggest loss in biodiversity.
Scientists say that even a one degree change, if
it comes quickly enough, can cause major
issues in ecosystems and push many species
into extinction. With the slight rise in global
temperature that hasvii been witnessed
already, patterns in animal migration have
Deforestation
©Guardian UK
changed and flowering times for plants have
changed. These types of changes can cause mismatches in ecosystems and can greatly alter food
chains. Many natural processes of animals are based on dependent variables. For example birds
will only nest when there is available food. All of these processes are disrupted if there are changes
to the natural patterns.
In addition, climate change and human activities together have caused many problems not just for
biodiversity loss, but also for humans. Natural disasters, like floods and mudslides, have been
increasing. A main reason for this is because of the increase of deforestation in many areas. The
forest ecosystems are so greatly destabilized through deforestation, that they can no longer sustain
the large amounts of rainfall. Further, many of the species are also unable to adapt to the smaller
living area. This too causes for a destabilization of the forest.
AGRICULTURE AND BIODIVERSITY LOSS
Agriculture also has a great
effect on biodiversity loss. This
occurs through two ways,
domesticating certain crops
and the use of fertilizers in
agriculture.viii
Domesticating of crops means
that certain crops and seeds
are used more often to grow
food than others. Certain
varieties of corn and wheat are
extinct today because most
farms only used the high
yielding seeds. According to
the United Nations Food and
Agriculture Organization, over
75% of crop diversity has been
lost since these new agriculture
practices have been used in the
20th century.
Another issue with modern day agriculture practices is the use of monocultures on farms. What
this means is the use of only one crop throughout a large area of space when compared to using
several different crops on the same space. This practice also makes these crops at a greater risk for
catching diseases and to be eaten by pests. Since there is only one crop on a large area as compared
to several crops over a large area, pests are more easily able to find their food and in turn destroy
the crop.
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Monocultures: the cultivation of a single crop
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This practice of monoculture is also the reason why many farms are using more pesticides and
fertilizers. Since only one crop is being planted, no nutrients that other crops may add to the soil
are available. Further, by planting only one crop on the same soil time after time, the soil becomes
depleted of the necessary nutrients that are needed to grow the crop.ix
Dead zone and healthy ocean water
©Carleton
Fertilizers are used to add nutrients to the soil to make
the crops grow. The biggest issue that occurs through the
use of fertilizers is the increase of nitrogen in many of
thex water supplies that farm water runs into. Nitrogen
pollution causes an increase of water plant and algae
growth in lakes, rivers, and oceans. As the plants and
algae die, the microorganisms that eat the plants, use up
a large amount of oxygen in the water, cause “dead
zones”. In these dead zones, since there is no oxygen, no
other living animal or plant can survive. This is a huge
disturbance to the lake, river, or even ocean ecosystem.
OVEREXPLOITATION AND BIODIVERSITY LOSS
Overexploitation is when a resource or animal is over used, over worked, or otherwise pushed
towards depletion or extinction. Overexploitation can be seen in both the natural resources that we
use and in wildlife. One example of overexploitation that can be seen is the large amounts of
deforestation that is occurring around the world. Humans are over using trees for paper and
construction. When deforestation occurs, not only is there a great loss in biodiversity, there are also
changes to the ecosystem. As you read earlier
deforestation can result in floods and even dangerous
mudslides.xi
Overexploitation also occurs in wildlife. One example of
this is the fishing industry. Every year, over 80 million
fish are caught for humans to eat. This not only shrinks
populations of fish, but they many times the way fish are
caught also disrupts the marine ecosystem. Large nets
that are used to catch fish also catch other marine
animals. In addition many of the equipment used to
harvest fish are damaging to marine ecosystem by
spilling oil or other materials into the water harming
marine animals and plants.xii
Ivory Trade
©China.org
Another example of overexploitation occurs in the trading of animals and their parts. This type of
trade can also occur with plants. Animals are taken from their habitats and sold to animal
collectors or even worse made into gifts. For example, endangered species of butterflies are caught
and sold to collectors. Shells from turtles and crabs are decorated and sold as gifts in beach towns.
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All three forms of overexploitation greatly add toxiv biodiversity loss.xv xvi
Case Study: African Elephants and the Ivory Trade
Since 1979, poachers have uncontrollably hunted elephants for their tusks to be sold to China and
Japan. Ivory in China and Japan is not only a religious symbol, but also a luxury item to have.
In just ten years, the population of African elephants fell from 1.3 million to only 600,000. With
continuing hunting, the African elephant would soon become extinct.
In 1989, The United Nations Convention on International Trade in Endangered Species of Wild
Flora and Fauna (CITES) was passed. This international agreement between governments
provided varying levels of protection for species that are or may be in danger of extinction from
international trade, including the African elephants.
Since then, several African countries have been trying to overturn CITES. In 1999, Botswana,
Namibia, and Zimbabwe were allowed to experimentally hunt elephants again, for a one time sale
of ivory to Japan. In 2002, they were allowed to do the same sale. Since then, levels of illegal
poaching and trading of ivory have gotten out of control. Some 12 tons of ivory have been seized
by officials in just four incidents.
At this time, poaching and ivory sales have reach an unsustainable level not just for African
elephants, but most species of elephants. In order to stop the trade, the full ban on the trade from
CITES must be followed again.
PAST INTERNATIONAL ACTIONS
The concern for preserving biodiversity has grown considerably during the past few decades. The
United Nations has designated 2011-2020 as the international “Decade of Biodiversity”, bringing
focus to the issue on a global platform. A number of conventions and meetings have taken place in
recent years with a main focus on biodiversity. The Biodiversity Convention in 1992 in Rio de
Janeiro brought 150 countries to sign to Convention on Biological Diversity, officially confirming
countries’ commitments to create strategies to protect diverse species on earth. The World Summit
on Sustainable Development again brought world leaders together, creating a common goal of
reducing the current rate of loss of biodiversity by the year 2010. As the issue of biodiversity gained
prominence worldwide, the heads of state of the European Union confirmed in 2005 that all
European governments and members of civil society at every level, have taken the necessary
actions to halt the loss of biodiversity by 2010.
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There are an increasing number of incentive programs that give money to landowners who protect
their environment. There have also been an increasing number of special reserve sites where the
environment is meant to be strictly protected from damage and from loss of biodiversity. In the
scientific world, conservation biology has emerged as an applied science that aims to preserve
existing biodiversity and habitats. Conservationists search for ways to align human goals for
productivity with sustainable practices. They work to maintain the reproduction of endangered
species. Zoos, for example, though not solving the problem of biodiversity loss, do act as temporary
reserves for such animals.
QUESTIONS TO CONSIDER
What factors have caused biodiversity loss in the past century?
Do you think the international treaties created in recent years to calm
biodiversity loss have been successful thus far?
Has your country signed onto the Biodiversity resolutions?
What is the biodiversity situation in your country?
Civil Society: the elements that make up a democratic society
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CITATIONS AND PHOTO CREDIT
Photo Credit: http://thepimmgroup.org/1022/defining-biodiversity-toward-a-consensus/
http://www.ecokids.ca/pub/eco_info/topics/biodiversity/index.cfm
iii “Ibid.”
iv http://science.jrank.org/pages/3502/Ice-Age-Refuges.html
v http://www.cbd.int/2010/biodiversity/#tab=1
vi http://www.cbd.int/2010/biodiversity/#tab=1
vii Photo Credit: http://www.guardian.co.uk/commentisfree/commentisfree+environment/deforestation
viii http://www.landinstitute.org/pages/Picone%20and%20Van%20Tassel%202002.pdf
ix http://www.landinstitute.org/pages/Picone%20and%20Van%20Tassel%202002.pdf
x Photo Credit: http://serc.carleton.edu/microbelife/topics/deadzone/index.html
xi http://www.ecokids.ca/pub/eco_info/topics/biodiversity/human_activities.cfm
xii http://www.ecokids.ca/pub/eco_info/topics/biodiversity/human_activities.cfm
xiii http://www.ecokids.ca/pub/eco_info/topics/biodiversity/human_activities.cfm
xiv Photo Credit: http://www.china.org.cn/environment/2012-02/17/content_24661911.htm
xv http://www.bloodyivory.org/stop-the-ivory-trade
xvi http://www.bloodyivory.org/cites
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