BIODIVERSITY - My Class

porcupineideaBiotechnology

Dec 16, 2012 (4 years and 10 months ago)

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the variety and number of life forms on Earth



Over 1.7 million kinds of living things had been
identified by 2010, the International Year of
Biodiversity

Levels of Diversity


Biodiversity is a product of millions of years of
evolution as organisms have adapted to changes in the
environment.


Since biodiversity allows systems to adapt to changing
circumstances over time, it is often used to measure
the health of biological systems.



Genetic Diversity


All of the different forms of
genes present in a particular
species


Within a species, slight
differences in genes occur
from one individual to
another


These small differences allow
populations to adapt to
changes in environmental
conditions and evolve over
time which helps to ensure
the survival of the species.

Genetic Diversity


Pros and cons of
monoculture; animal
breeding; genetic
engineering;
antibiotics and their
effects on the diversity
of bacterial
populations

Genetic Diversity

Species Diversity


the variety of species in
an ecosystem and the
number of individuals
within each of those
species


Having a variety of
species allows
ecosystems to survive
environmental changes
such as drought, plagues,
or disease outbreaks.

Species Diversity


Each species contributes
to the whole ecosystem
and, without the actions
of each species, the
ecosystem and other
organisms may not be as
successful.


Ecosystem Diversity


Refers to a diverse range of
habitats, the various
organisms that live in the
habitats, and the
relationships that connect
them


Ecosystems range in size:
from single organisms with
the microorganisms living
in their intestines, to
organisms in soil profiles
(right photo) to a tropical
rainforest

Diversity of Interactions within an
Ecosystem


Species support each
other and contribute to
the stability and
productivity of their
ecosystems.


Species depend on each
other for:


Food supply


Protection


Transportation


Reproduction


Hygiene


digestion


Diversity of Habitats within an
Ecosystem


The range of physical sizes, shapes, and distribution of
the individuals, as well as habitats and communities in
an ecosystem, are together referred to as
STRUCTURAL DIVERSITY.


Creates microhabitats with a variety of
abiotic

conditions

Structural Diversity

Tree plantation

vs.

Old
-
growth forest

The Importance of Biodiversity


Ecosystems that have
a high biodiversity
tend to be healthier
and more resilient to
changes in the
environment.


Biodiversity provides
the raw materials for
medicine, food and
agriculture.

The Importance of Biodiversity


Biodiversity helps to
maintain life
-
sustaining
services, conditions, and
processes such as:


pollination of plants


micro
-
organisms make
nutrients available and
break down toxic
substances in water and
soil


ecosystems cycle C, N, and
O, and clear air, purify
water, control erosion,
prevent floods, and modify
climate


Human Interference



Many human activities are causing species extinction
and therefore, reducing biodiversity .


Examples: loss of natural habitat due to agriculture,
forestry, urban expansion, mineral extraction;
introduction of invasive species; over
-
harvesting of
wild populations; air and water pollution; production
of greenhouse gases causing human
-
induced climate
change

The Effects of Reduced Biodiversity

Loss of biodiversity :


threatens our food supply


eliminates sources of natural medicines and potential
new medicines


has a significant economic impact on tourism and
forestry when accompanied by habitat destruction


has the potential to cause serious disruptions in
biogeochemical cycles, including normal carbon
uptake by natural ecosystems.

Keystone Species


Often the presence or
absence of a single
keystone species can
have a dramatic impact
on an ecosystem.

Focus Questions:


Outline the importance of
the honeybee in our global
environment.


What is colony collapse
disorder?


What are some causes of
colony collapse?


Discuss the relationship
between genetic diversity and
the decline in honeybee
populations.


How has a decline in
honeybees affected species
diversity in various
ecosystems?

To Bee or Not to Bee
(The Nature of Things; 2010)