Learning outcomes:
1. Explain the importance of genetic diversity for the conservation of species
2. Understand the importance of genetic tools and concepts to construct breeding plans and
programmes for conservation
3. Apply these tools in various practical situations, such as in the Studbook assignment
4. Identify the major evolutionary forces that shape genetic variation in wild populations;
5. Explain the concept of effective population size
6. Calculate inbreeding coefficients in small populations;
7. Explain the dynamics of genetic variation due to population size and structure;
8. Evaluate and construct management and conservation breeding plans and programmes.
Ch1: Introduction
Why conserve biodiversity?
Extinctions => part of life
• ~40 million species alive today
• ~40 billion estimated species that ever lived
• 1 out of thousand currently alive
• 99.9% of species extinct
o Bad genes or bad luck?
o Why bother?
Why bother?
• Individual species are not important, they are inter-changeable
• Value of biodiversity is debatable
• As long as not all species die out, there is no serious problem
What makes biodiversity special?
• Why are we not worried about loss of TV-aerials?
Reasons why to conserve biodiversity
• Biodiversity = important
- It defines nature
• It is nature, our natural environment, that we live in
o Biodiversity = useful and/or has economic value
- Bio-resources
- Ecosystem services
- Ethics/ aesthetics
,Ethics/aesthetics
• It is beautiful/unique & needs to be preserved
• Humans like to collect, order & preserve
• We have moral obligation to study life before it is lost forever
• Humans do not have the right to drive others to extinction
Bio-resources
• Nature provides us with essential resources, from wood to pharmaceuticals
• Gone is gone => very many unique compounds may get lost with extinction
• It is important for sustaining food supply => natural genetic variation drives animals & crop
breeding to sustain human population
Ecosystem services
• Essential biological functions benefitting mankind such as O2 production, nutrient cycles &
water purification
• Loss of diversity in ecosystems may cause ecosystems to collapse
• Loss of diversity makes us vulnerable
- Mono-cultures & pathogen outbreak
Speciation & extinction
• Live on earth characterized by repeated events of speciation & extinction
• Speciation => study evolutionary processes that shape genetic variation within &
between populations & species
• Extinction => study the genetic, demographic & stochastic processes that cause
extinction
o Conservation genetics motivated by need to reduce current rates of extinction &
preserve biodiversity
Dynamics of extinction: 5 largest mass extinctions
1: Late Ordovician -> 100 families extinct, more
than half of bryozoan & brachiopod species extinct
2: Late Devonian -> 30% of all animals extinct
3: End of Permian -> Trilobites extinct, 50% of all
animals, 95% of all marine species & many trees
4: Late Triassic -> 35% of all animals die out, most
early dinosaurs & synapsids extinct (except
mammals)
5: Cretaceous-Tertiary boundary -> ~50% of all life
forms extinct, including dinosaurs
,Dynamics
• Individuals struggle for existence -> survival of the fittest
• Demographic stochasticity
• Populations go extinct, which can cause species to go extinct
• Extinction also creates opportunities for speciation due to empty niches
6th extinction
Problem now: speed of extinction
due to human impact
Current extinction rate birds &
mammals -> 100-1000 x greater
than expected naturally
Primary cause => rapid growth of human population
• Severe impact on natural habitats & species persistence
Causes extinction => human impact
• We are with many & still increasing (7 billion)
• Habitat loss (panda)
• Introduced species (rats, dogs, rabbits in Australia)
• Overexploitation (many fish species)
• Pollution (river dolphin in China)
Human impact => if we cannot remove these threats, we cannot prevent more & more species to
become extinct
• Overkill/exploitation
- Poachers
- Whaling (for some species: <3% left)
• Habitat destruction & fragmentation
- Smaller populations more likely to go extinct
• Disturbance
- E.g. presence of humans
, • Introduced species
- Human themselves
- House mouse at Cough island eats young birds
Reduction in population size => stochastic effects
1. Environmental: rainfall, food supply, catastrophes
2. Demographic: variation birth/death rate, sex ratios
3. Genetics: effects in small populations
- Loss of genetic variation -> loss of adaptive potential
- Inbreeding depression -> deleterious effects of recessive mutations
Extinction vortex
Genetic drift => reduction individual fitness
& loss of genetic diversity results in loss of
population adaptability
Who is at risk?
• International Union for Conservation of Nature (IUCN)
1. Lower risk
2. Vulnerable
3. Endangered
4. Critically endangered
• More systems used, but:
- IUCN only internationally recognized system
- IUCN system forms basis of Red books of threatened species
• Important: species differ in potential risk
- Biology matters: life history, generation times, size
- Special needs: generalists vs specialists
o Listing provides scientific foundation of legal protection
1. Explain the importance of genetic diversity for the conservation of species
2. Understand the importance of genetic tools and concepts to construct breeding plans and
programmes for conservation
3. Apply these tools in various practical situations, such as in the Studbook assignment
4. Identify the major evolutionary forces that shape genetic variation in wild populations;
5. Explain the concept of effective population size
6. Calculate inbreeding coefficients in small populations;
7. Explain the dynamics of genetic variation due to population size and structure;
8. Evaluate and construct management and conservation breeding plans and programmes.
Ch1: Introduction
Why conserve biodiversity?
Extinctions => part of life
• ~40 million species alive today
• ~40 billion estimated species that ever lived
• 1 out of thousand currently alive
• 99.9% of species extinct
o Bad genes or bad luck?
o Why bother?
Why bother?
• Individual species are not important, they are inter-changeable
• Value of biodiversity is debatable
• As long as not all species die out, there is no serious problem
What makes biodiversity special?
• Why are we not worried about loss of TV-aerials?
Reasons why to conserve biodiversity
• Biodiversity = important
- It defines nature
• It is nature, our natural environment, that we live in
o Biodiversity = useful and/or has economic value
- Bio-resources
- Ecosystem services
- Ethics/ aesthetics
,Ethics/aesthetics
• It is beautiful/unique & needs to be preserved
• Humans like to collect, order & preserve
• We have moral obligation to study life before it is lost forever
• Humans do not have the right to drive others to extinction
Bio-resources
• Nature provides us with essential resources, from wood to pharmaceuticals
• Gone is gone => very many unique compounds may get lost with extinction
• It is important for sustaining food supply => natural genetic variation drives animals & crop
breeding to sustain human population
Ecosystem services
• Essential biological functions benefitting mankind such as O2 production, nutrient cycles &
water purification
• Loss of diversity in ecosystems may cause ecosystems to collapse
• Loss of diversity makes us vulnerable
- Mono-cultures & pathogen outbreak
Speciation & extinction
• Live on earth characterized by repeated events of speciation & extinction
• Speciation => study evolutionary processes that shape genetic variation within &
between populations & species
• Extinction => study the genetic, demographic & stochastic processes that cause
extinction
o Conservation genetics motivated by need to reduce current rates of extinction &
preserve biodiversity
Dynamics of extinction: 5 largest mass extinctions
1: Late Ordovician -> 100 families extinct, more
than half of bryozoan & brachiopod species extinct
2: Late Devonian -> 30% of all animals extinct
3: End of Permian -> Trilobites extinct, 50% of all
animals, 95% of all marine species & many trees
4: Late Triassic -> 35% of all animals die out, most
early dinosaurs & synapsids extinct (except
mammals)
5: Cretaceous-Tertiary boundary -> ~50% of all life
forms extinct, including dinosaurs
,Dynamics
• Individuals struggle for existence -> survival of the fittest
• Demographic stochasticity
• Populations go extinct, which can cause species to go extinct
• Extinction also creates opportunities for speciation due to empty niches
6th extinction
Problem now: speed of extinction
due to human impact
Current extinction rate birds &
mammals -> 100-1000 x greater
than expected naturally
Primary cause => rapid growth of human population
• Severe impact on natural habitats & species persistence
Causes extinction => human impact
• We are with many & still increasing (7 billion)
• Habitat loss (panda)
• Introduced species (rats, dogs, rabbits in Australia)
• Overexploitation (many fish species)
• Pollution (river dolphin in China)
Human impact => if we cannot remove these threats, we cannot prevent more & more species to
become extinct
• Overkill/exploitation
- Poachers
- Whaling (for some species: <3% left)
• Habitat destruction & fragmentation
- Smaller populations more likely to go extinct
• Disturbance
- E.g. presence of humans
, • Introduced species
- Human themselves
- House mouse at Cough island eats young birds
Reduction in population size => stochastic effects
1. Environmental: rainfall, food supply, catastrophes
2. Demographic: variation birth/death rate, sex ratios
3. Genetics: effects in small populations
- Loss of genetic variation -> loss of adaptive potential
- Inbreeding depression -> deleterious effects of recessive mutations
Extinction vortex
Genetic drift => reduction individual fitness
& loss of genetic diversity results in loss of
population adaptability
Who is at risk?
• International Union for Conservation of Nature (IUCN)
1. Lower risk
2. Vulnerable
3. Endangered
4. Critically endangered
• More systems used, but:
- IUCN only internationally recognized system
- IUCN system forms basis of Red books of threatened species
• Important: species differ in potential risk
- Biology matters: life history, generation times, size
- Special needs: generalists vs specialists
o Listing provides scientific foundation of legal protection
