Chapter 7.2 Introduction

What does extirpation mean?

• The complete extinction of a species globally

• The disappearance of a particular population from a given area, but not the entire species globally

• The introduction of a new species into an ecosystem

• The natural process of species evolution

Answer explanation

Extirpation refers to the disappearance of a particular population from a given area, but not the entire species globally.

What is the background rate of extinction?

• The rate at which species evolve into new forms

• The rate at which species are introduced into new habitats

• The rate at which species go extinct due to human activities

• The rate at which species would typically go extinct before modern humans evolved

Answer explanation

The background rate of extinction refers to the rate at which species would typically go extinct before modern humans evolved, without human interference.

How often would one of every 1,000 mammal species typically go extinct in the past?

• Every 100-1,000 years

• Every 1,000-10,000 years

• Every 10,000-100,000 years

• Every 100,000-1,000,000 years

Answer explanation

The correct answer is Every 1,000-10,000 years, based on the fossil record of mammal species extinctions

How many times have mass extinctions happened at least in Earth's history?

• 1 time

• 3 times

• 5 times

• 10 times

Answer explanation

Mass extinctions have occurred at least 5 times in Earth's history, making the correct answer choice 5 times.

In 2022, scientists estimated the global extinction rate to be how many times greater than the usual background rate?

• 10 to 100 times

• 100 to 1,000 times

• 100 to 10,000 times

• 1,000 to 100,000 times

Answer explanation

The correct answer is 100 to 10,000 times greater than the usual background rate, as estimated by scientists in 2022.

What is an endangered species?

• A species that has already become extinct

• A species that is at serious risk of extinction

• A species that is not at risk

• A species that is overpopulated

Answer explanation

An endangered species is a species that is at serious risk of extinction, not one that has already become extinct or is overpopulated.

What does "threatened species" refer to?

• A species that is thriving and increasing in number

• A species that is at moderate risk of extinction

• A species that is likely to become endangered soon throughout all or part of its range

• A species that has been recently discovered

Answer explanation

Threatened species refer to a species that is likely to become endangered soon throughout all or part of its range, not a species that is thriving or recently discovered.

As of 2022, how many species are officially classified as "endangered" or "threatened"?

• 41,415 species

• 14,115 species

• 4,115 species

• 1,415 species

Answer explanation

The correct answer is 41,415 species, as of 2022, officially classified as 'endangered' or 'threatened'.

What does the Living Planet Index summarize?

• Economic trends of various countries

• Population trends for a set number of terrestrial, freshwater, and marine species

• Climate change patterns over the years

• Technological advancements in biodiversity research

Answer explanation

The Living Planet Index summarizes population trends for a set number of terrestrial, freshwater, and marine species.

Between which years does the Global Living Planet Index show a decline of 58 percent?

• 1980 to 2012

• 1970 to 2000

• 1970 to 2012

• 1980 to 2010

Answer explanation

The Global Living Planet Index shows a decline of 58 percent between 1970 to 2012, making that the correct choice.