4 .1 – Biodiversity in Ecosystems

4.1 – Biodiversity in EcosystemsIB Topics 2.1.1-2.1.7

Topic – Conservation and Biodiversity

Biodiversity Species Diversity

The variety of species per unit area

High species diversity = More complex

Biodiversity Habitat Diversity

The range of different habitats in an ecosystem

High habitat diversity = more niches

Biodiversity Genetic Diversity

The variety of genes present in a species

High genetic diversity = Better survival

Biodiversity Hotspots Areas of high biodiversity

Natural Selection New species arise through natural selection The fittest organisms survive and have more

offspring, changing species over time

Isolation and Natural Selection Isolation leads to

speciation (forming new species)

Isolation: Fences/roads/deforestation Deserts Rivers Islands

Plate Tectonics and Speciation Movement of tectonic

plates creates mountains, oceans, valleys, islands

This leads to speciation

Ex:

4.2 – Evaluating biodiversity and vulnerabilityIB Topics 2.1.1-2.1.7

Topic – Conservation and Biodiversity

Extinction Extinct

No members of a species remain

Extinct in the wild No members of a

species remain in the wild

Extirpated Locally extinct

Mass Extinctions 5 major mass

extinctions Up to 75% of all

species went extinct

Sixth Mass Extinction Countless extinctions

over the past 10000 years

Climate change & Humans

Extinction Rate Believed to be 10-100

species per year throughout natural history

Now believed to be much higher 89 mammals over the

past 400 years

Rainforests Have the highest

biodiversity on Earth 50% of all plant and

animal species Make 40% of Earth’s

oxygen

Rainforest Loss Up to 1.5 hectares

cleared per second Ranching &

Logging Growing population

living in the rainforest

Factors that make species prone to extinction:

Small Population Size Limited Distribution Specialists Low Reproductive

Capacity Poor Competitors Large Mammals Valuable Products Altruistic Species

IUCN Red List International Union

for the Conservation of Nature

Red List: An inventory of all

threatened species

Determining Conservation Status

Population size Reduction in

population size Geographic range Quality of habitat Probability of

extinction

Natural Factors that lead to loss of biodiversityNatural DisastersEnvironmental

DisastersHabitat

FragmentationPollution

Human Factors that lead to loss of biodiversityOverexploitation Invasive SpeciesDiseaseModern

Agricultural Practices

Factors that make species prone to extinction:

Small Population Size Limited Distribution Specialists Low Reproductive

Capacity Poor Competitors Large Mammals Valuable Products Altruistic Species

IUCN Red List International Union

for the Conservation of Nature

Red List: An inventory of all

threatened species

Determining Conservation Status

Population size Reduction in

population size Geographic range Quality of habitat Probability of

extinction

4.3 – Conservation of biodiversityIB Topics 4.3.1-4.3.5

Topic – Conservation and Biodiversity

Values of Biodiversity Products:

Timber/medicine Ecosystem

health/productivity Science Education Genetic diversity

Recreation & ecotourism

Aesthetic value Ethical reasons

Conservation Organizations

NGOs GOs Established

through international agreements

Ex: UNEP, IUCN

Not run by, funded by, or influenced by any country/government

Ex: WWF, Greenpeace

Conservation Organizations

NGOs Use of media Speed of

response Dimplomatic

constraints Political

influence Enforceability

GOs

Designing a Protected Area Large vs Small Large vs Many Close vs Separate Clumped vs Spread out Corridors vs Not connected Round vs Other shapes Buffer zone vs No buffer

Protected Areas The US has 7500+

protected areas covering over 1.25 million square miles

Zoos & Conservation Zoos bring

awareness to conservation

Zoos can help breed and reintroduce species