ES 4.1 LESSON Why is Biodiversity Important?

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Environmental Science, 1e
SUSTAINING YOUR WORLD
G. TYLER MILLER | SCOTT E. SPOOLMAN

4

Biodiversity and Evolution

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• Amphibians (frogs, toads, and salamanders) show great

biodiversity (6,700-plus species).

– Many amphibian populations have declined or vanished since 1980

(likely due to a combination of chemical pollution, habitat loss,
increased UV levels, warming climate).

– Amphibians are critical species: sensitive biological indicators, prey

on/serve as prey for numerous species, sources of medicine

• How can you study local biodiversity?

Case Study: Amphibians at Risk

Multiple Choice

Amphibians are often called "indicator species" in ecosystems as they are the first affected by chemical pollution. What has been happening to amphibian populations in the last 30 years?

• slight decline

• alarming decline

• slight increase

• impressive increase

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• Biological diversity, or biodiversity, is the variety of Earth’s

species, the genetic material they contain, the ecosystems in
which they live, and ecosystem processes such as energy
flow and nutrient cycling.

• Biodiversity is one of three scientific factors of sustainability.

4.1 What Is Biodiversity and Why Is It Important?

Multiple Select

Biodiversity can refer to...

• variety of genetic material in a species

• variety of ecosystems

• variety of species

• variety of abiotic factors

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• Species diversity describes the variety of species present in

an ecosystem and their abundance within that ecosystem.

• About 2 million of species identified on Earth
• Actual total likely ranges from 7–10 million, may be as many

as 100 million

Components of Biodiversity:
Species Diversity

Multiple Choice

How many species are known to be living on Earth?

• between 10,000 and 100,000

• between 1 and 2 million

• between 5 and 9 million

• between 10 and 50 million

Multiple Choice

Which of these is the best example of species diversity?

• Dogs have a wide variety of characteristics, from huge Great Danes to tiny Chihuahuas.

• Rainforests tend to have a wide variety of plants, birds, insects and small mammals living together

• The United States contains grasslands, deserts, wetlands, forests and mountains.

• Rainforests are able to quickly cycle carbon, nitrogen and phosphorus in and out of the biosphere.

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• Genetic diversity is the variety of genes found in a population

or in a species.

– Genetic information gives rise to traits that are passed on to

offspring.

– Greater genetic diversity means species have a better chance of

surviving and adapting to environmental changes.

Components of Biodiversity:
Genetic Diversity

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Genetic Diversity

Multiple Choice

Which is a benefit of genetic diversity?

• greater chance of a species adapting to change and surviving

• greater chance of an organism hunting successfully

• greater chance of an environment providing ecosystem services

• greater chance of habitats changing due to climate change

Multiple Choice

Which of these is the best example of genetic diversity?

• Dogs have a wide variety of characteristics, from huge Great Danes to tiny Chihuahuas.

• Rainforests tend to have a wide variety of plants, birds, insects and small mammals living together

• The United States contains grasslands, deserts, wetlands, forests and mountains.

• Rainforests are able to quickly cycle carbon, nitrogen and phosphorus in and out of the biosphere.

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• Ecosystem diversity refers to Earth’s diversity of biological

communities.

– Deserts, grasslands, forests, mountains, oceans, lakes, rivers, and

wetlands

– Biomes: major habitations/large ecosystems with distinct climates

and species

Components of Biodiversity:
Ecosystem Diversity

Multiple Select

A biome is a large area of similar ecosystems. Which two characteristics define biomes?

• climate

• abiotic factors

• species present

• human interaction

Multiple Choice

Which of these is the best example of ecosystem diversity?

• Dogs have a wide variety of characteristics, from huge Great Danes to tiny Chihuahuas.

• Rainforests tend to have a wide variety of plants, birds, insects and small mammals living together.

• The United States contains grasslands, deserts, wetlands, forests and mountains.

• Rainforests are able to quickly cycle carbon, nitrogen and phosphorus in and out of the biosphere.

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• Functional diversity is the variety of processes that occur

within ecosystems, such as energy flow and matter cycling.

– Concerns variety of roles organisms play in their communities and

the impact these roles have on the overall ecosystem

• More than one species may share same function.

• If an ecosystem contains many species that share functional traits, that

ecosystem will be better able to withstand some species loss without losing
functionality.

Components of Biodiversity:
Functional Diversity

Multiple Select

Functional diversity is about the variety of processes in an ecosystem, such as which TWO of these

• matter cycling

• energy flow

• species adapting to change

• passing genes to next generation

Multiple Choice

Which of these is the best example of functional diversity?

• Dogs have a wide variety of characteristics, from huge Great Danes to tiny Chihuahuas.

• Rainforests tend to have a wide variety of plants, birds, insects and small mammals living together.

• The United States contains grasslands, deserts, wetlands, forests and mountains.

• Rainforests are able to quickly cycle carbon, nitrogen and phosphorus in and out of the biosphere.

© 2017 Cengage Learning. All Rights Reserved.

• Biodiversity ensures ecosystems against a decline in their

functioning because many species provide greater
guarantees of functioning even if others fail.

• Biologically diverse ecosystems are more likely to contain

species with traits that enable them to adapt to changes in
the environment.

Insurance Hypothesis

Multiple Choice

When an ecosystem has multiple species that can accomplish the same purpose, if one of them dies off the others can still get the job done. This is known as...

• ecosystem services

• natural capital assurance

• insurance hypothesis

• succession theory

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• Biodiversity is vital to maintaining natural capital that keeps

humans alive and supports their economies.

– Provides raw materials for resources such as food, medicine,

building materials, fuel

– Provides ecosystem services such as air and water purification,

topsoil renewal, decomposition of wastes, pollination

– Allows for evolution of new species and ecosystem services

Biodiversity Builds Natural Capital

Multiple Choice

The ecosystem services and natural resources that a biodiverse ecosystem provides are known as...

• insurance

• natural capital

• natural income

• nutrient cycling