Modern extinction

The sixth mass extinction

Objectives• Define extinction.• Give examples of (1) past mass extinctions (2) and recent

species extinctions.• Compare current extinction rates with background

extinction rates.• Explore the causes of extinction.• Analyse the connection between recent extinctions and

human activities.

Questions

• Why do some species become endangered or extinct?• Which species have become extinct in modern times? • What are the characteristics of mass extinctions in the past? • How do modern extinction rates compare with natural

(background) rates?• What are the connections between human activities and

species extinctions?

The world is singing

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The world is singing

What are your favourite animals?Describe the natural habitats in which those animals live.

http://macaulaylibrary.org/

What is ?

What extinct species do you know of?

Try to remember some movies and books about animals that no longer exist on Earth.

extinction

Extinct species

Tyrannosaurusrex

Extinct species

Woolly mammoth Mammuthus primigenius

Extinct species

Passenger pigeon Ectopistes

migratorius

Extinct species

Dodo Raphus cucullatus

Defining extinction

Write your definition of the word ‘extinction’.

Use the word ‘extinction’ in a sentence.

Understanding extinction

You will learn about the concept of extinction and obtain evidence for actual extinctions in Earth’s

history and in modern times.

Mass extinction events

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Mass extinction events

Research online and create a timeline of past mass extinctions.

Look out for…• The different classifications and levels of species involved in

mass extinctions events (taxonomic levels)• Different measures of extinction:

o per cent of taxonomic levelo extinction rate (e.g. families lost per million years)

Mass extinction events

Compare these two graphs. They show mass extinctions over time.

Mass extinction events: Resource

Choose a mass extinction event.

Explaining extinction

Create a resource explaining your chosen mass extinction event. Types of resources include:• Web page• Digital slide presentation• E-brochure

Your resource should include:• fossil and radiometric evidence for dating the event• kinds of species that went extinct• severity of the event• scientific hypotheses that explain the event

Factors that contribute to extinction

Write a list of possible contributing factors to species extinction.

Place those factors into two categories:• natural influences• human influences

Mass extinction today: Vanishing species

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Case study concept map

With your group:

Select a species that has gone extinct in modern times. Create a concept map to describe the causes and consequences of the extinction.

Case study concept map: Resources

Case study concept map

Include key data in your concept map: • species scientific name• illustrations or photos if available• dates of discovery and extinction• biogeographical data

o locationo initial population sizeo ecology and behaviour

• causes of extinction• ecological effects of the extinction• possible actions that may have prevented the extinction

Your ideas!

Create a list of activities that publicise and educate about a possible sixth

mass extinction.

Ensure that your activities:• are feasible and realistic• do not require funding• ideally could be conducted in a school setting

Reflection

• Write a short passage describing characteristics of past mass extinctions.

• Describe how modern extinction rates compare with natural (background) rates.

• Describe five kinds of human activities that result in species extinctions.

• List three species that have become extinct due to human activities and the causes of those extinctions.

ResourcesData • http://evolution.berkeley.edu/evolibrary/images/evo/extinction_graph2. gif• https://www.e-education.psu.edu/earth103/sites/www.e-education.psu.edu.earth103/files/module11/mass_e

xtinctions.png

Websites• https://www.e-education.psu.edu/earth103/node/713 • http://science.nationalgeographic.com/science/prehistoric-world/mass-extinction/• http://www.bbc.co.uk/nature/extinction_events• http://www.pbs.org/wgbh/evolution/library/03/2/l_032_04.html• http://www.iucnredlist.org/• http://www.onekind.org/be_inspired/top_10_lists/extinct/• https://app.discoveryeducation.co.uk/player/view/assetGuid/33fe300d-42ab-4f9e-a2be-fbe41122b9c4• https://app.discoveryeducation.co.uk/player/view/assetGuid/94dbbf27-e949-48e7-ba8e-4dec9e19e21b