Biodiversity at Risk

What tends to follow whenever people colonize islands and continents?

• Technological advancements

• Economic prosperity

• Waves of extinctions

• Cultural exchange

What happened to the birds after the Polynesians reached Hawaii?

• They migrated to other islands

• Their population doubled

• Half of them went extinct

• They evolved rapidly

How many species of large vertebrates died off in Australia after the Aborigines arrived?

• Dozens

• Thousands

• None

• Hundreds

What is the term used when the last member of a species dies?

• Extirpation

• Endangerment

• Extinction

• Depletion

Before modern humans evolved, how often would a mammal species typically go extinct?

• Every 10,000–100,000 years

• Every 1000–10,000 years

• Every 100,000–1,000,000 years

• Every 100–500 years

What is the current global extinction rate compared to the usual background rate?

• 10 to 100 times greater

• 1000 to 10,000 times greater

• Same as the background rate

• 100 to 1000 times greater

What does an endangered species indicate?

• It is thriving in its habitat

• It is at serious risk of extinction

• It has a stable population

• It is only found in zoos

Between 1970 and 2005, by how much did the Living Planet Index fall?

• Nearly 10 percent

• Nearly 40 percent

• Nearly 30 percent

• Nearly 20 percent