Mass Extinctions and Recovery

What is the significance of the Ovis mass extinction event?

• It marked the beginning of the Phanerozoic Eon.

• It was the last of the big five mass extinctions.

• It was the only extinction event to affect land animals.

• It was the first of the big five mass extinctions.

Why is there a lack of fossil records before the Phanerozoic Eon?

• The Earth's surface was too volatile for fossilization.

• Life had not yet evolved on Earth.

• Life forms lacked hard parts like skeletons and shells.

• There were no mass extinctions before this period.

What were the two main pulses of the Ovis mass extinction?

• Volcanic eruptions followed by asteroid impacts.

• Sea level rise followed by sea level fall.

• Massive earthquakes followed by tsunamis.

• Rapid cooling and glaciation followed by rapid warming.

What does the new fossil assemblage discovered in South China suggest?

• Land animals were the first to recover after the extinction.

• Marine life recovered quickly after the Ovis extinction.

• The extinction event had no impact on marine life.

• The deep sea remained lifeless for millions of years.

Which organisms are typically the first to recover after mass extinction events?

• Complex mammals and birds.

• Opportunistic and simple organisms like sponges.

• Large reptiles and amphibians.

• Advanced fish and marine mammals.

How do foundational organisms like sponges contribute to ecosystem recovery?

• They provide food for larger predators.

• They create habitats that support diverse life forms.

• They increase the acidity of the oceans.

• They prevent the spread of diseases.

What role do algae and bacterial mats play in post-extinction recovery?

• They consume all available oxygen.

• They are primary producers that generate oxygen.

• They deplete nutrients from the environment.

• They block sunlight from reaching other organisms.

What is a major factor that influences the duration of recovery after a mass extinction?

• The speed of the extinction event.

• The presence of volcanic activity.

• The size of the organisms that survived.

• The availability of land for colonization.

Why is it important to study past mass extinction events?

• To identify ancient civilizations.

• To find new fossil fuels.

• To understand the resilience of modern ecosystems.

• To predict future asteroid impacts.

What environmental changes are currently threatening marine ecosystems?

• Rising sea levels.

• Increased volcanic activity.

• Ocean anoxia and acidification.

• Decreased sunlight due to dust clouds.