Questions and Answers
Why do we say that we are now experiencing an extinction crisis?
Which of the following provides the best evidence of a biodiversity crisis?
Why are current extinctions a concern to environmentalists?
Which of the following terms includes all of the others?
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What is the difference between an endangered species and a threatened species according to the U.S. Endangered Species Act?
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What would be the most serious consequence of a decrease in global biodiversity?
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Which of the following is the most direct threat to biodiversity?
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According to most conservation biologists, what is the single greatest threat to global biodiversity?
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What are relatively small geographic areas with high concentrations of endemic species called?
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What can the air pollutants from burning fossil fuels cause?
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What is the main cause of increased CO₂ in Earth's atmosphere over the past 150 years?
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What is considered the single greatest threat to biodiversity?
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Which strategy would most rapidly increase the genetic diversity of a population in an extinction vortex?
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Study Notes
Extinction Crisis
- 99% of all species that ever lived are now extinct, but current extinction rates are alarming.
- The primary causes of this crisis include human activities threatening biodiversity and a high current extinction rate.
Evidence of Biodiversity Crisis
- A high rate of extinction serves as the strongest indicator of a biodiversity crisis.
Current Extinction Concerns
- Environmentalists are particularly worried due to the unusually high rate of current extinctions.
Definitions of Diversity
- Biodiversity encompasses species diversity, genetic diversity, and ecosystem diversity.
- It includes all other forms of diversity, making it the broadest term.
Endangered vs Threatened Species
- Endangered species are closer to extinction than threatened species, according to the U.S. Endangered Species Act.
Consequences of Decreased Biodiversity
- The most critical outcome of reduced biodiversity is the potential loss of ecosystem services essential for human life.
Direct Threats to Biodiversity
- Habitat destruction is identified as the most direct threat to biodiversity.
Greatest Threat to Global Biodiversity
- Alteration or destruction of physical habitat stands out as the most significant threat to global biodiversity, surpassing other factors like pollution and overexploitation.
Biodiversity Hotspots
- Areas with high concentrations of endemic species and many endangered species are termed biodiversity hot spots.
Air Pollution and Biodiversity
- Burning fossil fuels generates pollutants responsible for multiple environmental issues, including extreme acid rain and fish die-offs.
Increase in Atmospheric CO₂
- The rise in atmospheric CO₂ levels over the last 150 years is mainly attributable to burning more fossil fuels.
Greatest Threat Recap
- Habitat alteration, fragmentation, and destruction are considered the single greatest threat to biodiversity.
Strategies to Increase Genetic Diversity
- Introducing new individuals from other populations can quickly boost genetic diversity in a population facing extinction challenges.
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Description
Explore the pressing issue of the biodiversity crisis and the alarming rates of extinction. This quiz covers the definitions of biodiversity, the difference between endangered and threatened species, and the consequences of decreased biodiversity on ecosystem services. Test your knowledge on the factors contributing to extinct species and the importance of conservation efforts.
