In the current biodiversity crisis, the extinction rate is ______ times the "background" extinction rate.Multiple choice question.3,000 to 10,00010 to 90100 to 1,00010 to 50

The current extinction rate is similar toMultiple choice question.the background extinction rate.the five mass extinctions that have occurred in the past.that predicted by the five forces of evolution.the normal disappearance rate of species before human intervention.

Biologists calculate that species extinctions are currently __________ times the rate seen previously in Earth’s history when there were no unusual geological or climatic events occurring.Question 18Select one:a.5-10b.50-100c.500-1000d.5000-10,000

Which choices are included in the definition of "mass extinction"? A. The event must be global B. All ecologies must be involved C. The duration of the event must be short D. The number of species extinction must exceed 30% existing at the time

The rate of species extinction on Earth is currently very high—perhaps as high as it has been since the time of the dinosaur extinction. Which of the following disruptions is not a major cause of this high extinction rate? Acid rain Climate change Earthquakes Habitat Destruction

_____________ occurs when a large number of species goes extinct over a relatively short period of time.a.Extinctionb.Extirpationc.Mass Effectd.Mass Extinction