What is Conservation Genetics? -- Application of

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• What is Conservation Genetics? -- Application of
• genetics to preserve species as dynamic entities
• capable of coping with environmental change and
• encompasses
• genetic management of small populations
• resolution of taxonomic uncertainties
• defining management units within species
• use of molecular genetic techniques in
• forensics understanding species biology.

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When a population or species disappears, all
the genetic information carried by that
population or species is lost! When a contiguous
population is fragmented into many small
populations, genetic diversity within each may
decay over time Gene pools are becoming
diminished and fragmented into gene puddles
(Thomas Foose, 1983)
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Why Genetics? Evolution is the single most
unifying organizational concept in all of biology
and should play a prominent role in conservation
as well. Evolution is dynamic and change is
expected. ecological systems are dynamic and
generally not in equilibrium. The best way to
manage such dynamic systems is a Conservationist
rather than Preservationist approach.
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• Three biological reasons to believe genetics can
• make important contribution to conservation
• biology.
• Fundamental theorem of natural selection
• tells us that the rate of evolutionary change
• in a population is proportional to the amount
• of genetic diversity available.

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Darwin-Wallace Theory of Natural Selection If
supplied with sufficient nutrients and
protection the total population size will
increase geometrically. However, due to high
death rates, geometric increase is not maintained
indefinitely. All species are variable
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Darwin-Wallace Theory of Natural Selection Those
individuals with variations of characters
that better enable them to survive and reproduce
will leave proportionally more offspring. This
results in the increase of the advantageous charac
ters in the next generation.
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• There is a consensus among population
• geneticists that heterozygosity, or high genetic
• variation within individuals or populations, is
• positively related to fitness.
• The global pool of genetic diversity represents
• all the information for all biological processes
• on the planet.
• Loss of such diversity will probably decrease
• the ability of organisms to respond to
• environmental changes and discard information
• potentially useful to humans.

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Basic problem linking genetics to conservation
is that small populations, whether in the wild
or captivity, tend to lose genetic variation over
time. This loss of variation may well increase
the probability of population extinction or
reduced opportunities for future adaptation
through evolutionary change.
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The basic thrust of conservation genetics and
the message to take from this course is We must
maintain natural patterns of genetic diversity at
many levels and thus preserve options for future
evolution!!!
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• Limitations of Genetics in Conservation Biology
• Application of genetics to conservation problems
• is a young science that is still developing.
• Many genetic techniques are not cheap and
• can be misused or misapplied.
• Plant and animal tissues must be obtained and
• properly handled.

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Genetic factors do not figure among the
four major causes of extinction (the Evil
Quartet) overkill, habitat destruction and
fragmentation, impact of introduced species, and
secondary cascade effects. Thus, although
genetic factors are major determinants of a
populations long-term viability, conservationists
can do more for a threatened population in the
short-term by managing its ecology.
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• Conservation Genetics deals with the genetic
• factors that affect extinction risk and genetic
• management regimes required to minimize these
• risks.
• There are 11 major genetic issues in conservation
• biology.
• The deleterious effects of inbreeding on
• reproduction and survival
• (inbreeding depression)

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• Loss of genetic diversity ability to evolve in
• response to environmental change.
• Fragmentation of populations and reduced
• gene flow.
• Random processes (genetic drift) overriding
• natural selection as the main evolutionary
• force.
• Accumulation and loss (purging) of deleterious
• mutations.

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• Genetic adaptation to captivity its adverse
• effects on reintroduction success.
• Resolving taxonomic uncertainties.
• Defining management units within species.
• Use of molecular genetic analyses in forensics.
• Use of molecular genetic analyses to understand
• aspects of species biology

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• Deleterious effects of fitness that sometimes
• occur as a result of outcrossing
• (outbreeding depression).

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• How is genetics used to minimize extinction?
• Reducing extinction risk by minimizing
• inbreeding and loss of genetic diversity.
• Identifying populations of concern.
• Resolving population structure
• Resolving taxonomic uncertainties
• Defining management units within species.

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• Detecting hybridization
• Non-intrusive sampling for genetic analyses.
• Defining sites for reintroduction.
• Choosing the best populations for reintroduction.
• Forensics.
• Understanding species biology

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Biodiversity -- the variety of ecosystems,
species, populations within species and genetic
diversity within species. Biological diversity
of planet is being rapidly Depleted due to
direct and indirect consequences Of
humans. Scale of this problem is enormous and
has been Termed the Sixth Extinction as its
magnitude Is comparable with that of the other
five mass Extinctions revealed in the geologic
record.
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Conservation genetics is motivated by the need to
reduce current rates of extinction and
to preserve biodiversity
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Why Conserve Biodiversity? Because humans Derive
many direct and indirect benefits from The living
world, we have a stake in conserving Biodiversity
for resources we use ecosystem services it
provides pleasure we derive from living
organisms ethical reasons
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Bioresources includes all food, many
pharmaceuticals, clothing fibers, rubber
timber with a value in billions of dollars
annually. About 25 of all pharmaceutical
prescriptions in the US contain active
ingredients derived from plants. The natural
world contains many potentially useful novel
resources Ants contain novel antibiotics that
are being investigated for use in human Medicine.
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Ecosystem Services -- essential biological
functions That are provided free of charge by
living organisms And which benefit mankind such
as Oxygen production by plants Climate
control by forests Nutrient cycling Natural
pest control Pollination of crop plants These
services have been valued at 33 trillion/year
or almost double the 18 trillion yearly global
national product!!!!
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Ethics -- The ethical justifications
for conserving biodiversity are simply that
one species does not have the right to
drive other species to extinction!
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The IUCN (the World Conservation
Union) Recognizes the need for conservation at
the Levels of genetic diversity species
diversity ecosystem diversity
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Based on the principles of population biology,
in 1996 the IUCN defined criteria to
classify species into Critically
Endangered Endangered Vulnerable Lower
Risk Extinct Extinct in the
wild Conservation Dependent Near
Threatened Data deficient
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It is of critical importance to
define endangerment as it is the basis for legal
protection for species. Most countries have
Endangered Species Acts that provide legal
protection for threatened species and usually
require the formulation of recovery
plans. Additionally, trade in threatened species
is banned by countries that have signed
the Convention on International Trade in
Enangered Species (CITES).
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Small populations suffer from inbreeding
loss of genetic diversity resulting in
elevated extinction risks. Consequently, a major
objective of genetic management is to minimize
inbreeding loss of genetic diversity.