module three - human impact on the enviroment

What is biodiversity?

The variety of life on Earth and the complex interactions among living organisms.

Why do scientists believe we may be experiencing a sixth mass extinction?

Species are disappearing at unusually rapid rates largely due to human activities.

What is genetic diversity?

The variation in genetic makeup among individuals within a species.

Why is genetic diversity important?

It provides the raw material for adaptation and increases a species' ability to survive environmental changes.

What can reduce genetic diversity within a species?

Natural disasters, disease outbreaks, overexploitation, and other events that drastically reduce population size.

What is a genetic bottleneck?

A sudden reduction in population size that decreases genetic diversity.

How does a genetic bottleneck affect future generations?

The recovering population has a smaller gene pool and reduced genetic variation.

Can genetic bottlenecks be caused by humans?

Yes, human activities can cause dramatic population declines that create bottlenecks.

What is heterozygosity?

The presence of different versions of genes within a population.

What does a decline in heterozygosity indicate?

Increased genetic similarity and reduced genetic diversity.

What is species richness?

The number of different species present in a habitat or ecological community.

What is species evenness?

How evenly individuals are distributed among different species in a community.

Why are species richness and species evenness both important for biodiversity?

Biodiversity depends on both the number of species present and their relative abundances.

Can two ecosystems have the same species richness but different biodiversity?

Yes, differences in species evenness can make biodiversity levels different.

How can invasive species affect species evenness?

They may dominate a community and reduce evenness.

What is the Shannon-Wiener Index (Shannon Index)?

A measure of biodiversity that combines species richness and species evenness into a single value.

Why is the Shannon Index useful?

It allows biodiversity comparisons between ecosystems.

What does a high Shannon Index value indicate?

High biodiversity with many species and relatively even distributions.

What does a low Shannon Index value indicate?

Low biodiversity with fewer species or domination by one species.

What is ecosystem diversity?

The variety of habitats, ecosystems, and ecological processes within a geographic area.

Why is ecosystem diversity important?

Different ecosystems provide different habitats and resources that support biodiversity.

How is ecosystem diversity related to species diversity?

Higher ecosystem diversity often supports higher species diversity.

What is a keystone species?

A species that has a disproportionately large effect on its environment relative to its abundance.

Why are keystone species important?

They help maintain ecosystem structure, function, and biodiversity.

What is a trophic cascade?

A series of ecosystem changes caused by the addition or removal of a key species.

What happened when grey wolves were removed from Yellowstone National Park?

Elk populations increased and caused overgrazing, leading to ecosystem degradation.

How did wolf reintroduction benefit Yellowstone ecosystems?

It restored ecological balance through a trophic cascade.

Why are plains bison considered a keystone species?

Their grazing, nutrient cycling, and seed dispersal shape ecosystems.

How do bison contribute to nutrient cycling?

Their feeding and waste distribution help recycle nutrients through ecosystems.

What is habitat fragmentation?

The breaking up of continuous habitat into smaller isolated sections.

What is the Ojibway Prairie Complex?

A collection of protected biodiverse habitats that support endangered species.

Why is the Ojibway Prairie Complex important?

It provides habitat for rare and endangered species, including the Massasauga rattlesnake.

What is the Massasauga rattlesnake?

The only venomous snake species native to Ontario.

What type of conservation is the Ojibway Prairie Complex an example of?

In-situ

What is in-situ conservation?

The protection and management of species within their natural habitats.

Why is in-situ conservation generally preferred?

It preserves species while maintaining natural ecosystem interactions.

What are examples of in-situ conservation?

Protected habitats, wildlife monitoring, and turtle nesting area protection.

What are the limitations of in-situ conservation?

It may not be sufficient when species populations become critically low.

What is ex-situ conservation?

The conservation of species outside their natural habitats.

What are examples of ex-situ conservation?

Captive breeding programs, zoos, aquariums, and gene banks.

What are the advantages of ex-situ conservation?

It can prevent extinction and allow controlled breeding of endangered species.

What are the disadvantages of ex-situ conservation?

It is expensive and may reduce natural behaviors and adaptation to wild environments.

What is a gene bank?

A facility that stores genetic material such as tissue, blood, sperm, eggs, or DNA for future conservation use.

Why are gene banks important?

They preserve genetic material that may assist future conservation or de-extinction efforts.

What is captive breeding?

The breeding of endangered species in controlled environments for conservation purposes.

Which conservation method generally provides the greatest ecological benefits?

In-situ conservation because it protects both species and ecosystems simultaneously.

What is biophilic urbanism?

An approach to city design that integrates nature into built environments for the benefit of people and wildlife.

What is the goal of biophilic urban design?

To connect people with nature while supporting biodiversity in urban areas.

How does biophilic urbanism support wildlife?

It incorporates habitat features directly into cities and built environments.

What is Tommy Thompson Park?

A restored urban wilderness area in Toronto created from a former industrial and landfill site.

Why is Tommy Thompson Park considered a conservation success?

It transformed degraded land into diverse wildlife habitats.

What does "conservation by design" mean?

Intentionally creating or restoring habitats to support biodiversity.

What is an endemic species?

A species found naturally in only one geographic location.

Why are California condors considered a conservation success story?

They were brought back from near extinction through intensive conservation efforts.

What factors contributed to California condor decline?

Lead poisoning, habitat destruction, and poaching.

What major action was taken in 1987 to save California condors?

The last remaining wild condors were brought into captivity.

Why did early captive-bred condors struggle after release?

They showed little fear of humans.

How did conservationists reduce human imprinting on young condors?

They used condor-shaped puppets during feeding.

What is nest guarding?

The monitoring and protection of nests to improve reproductive success.

Why is nest guarding still necessary for California condors?

The species remains vulnerable and requires ongoing conservation support.

What argument supports a hands-off conservation approach?

Habitat restoration should occur before species are reintroduced.

What argument supports a hands-on conservation approach?

Immediate intervention is necessary when extinction risk is extremely high.

How do California condors illustrate the debate between in-situ and ex-situ conservation?

Their recovery required both captive breeding and habitat management.

What is the overall goal of biodiversity conservation?

To protect species, genetic diversity, ecosystems, and ecological processes for the future.