Question

Since the origin and diversification of life on Earth, there have been five episodes of mass extinction of species. How is the sixth extinction, which is in progress, different from the previous episodes ?

• A. Lower extinction rate
• B. 10× faster
• C. Zero rate
• D. 100–1000× faster

Hint:

The Sixth Extinction is "Man-made" and moving at a "Super-speed" compared to the past natural extinctions.

Answer 1

The Correct Option is D

Step 1: Understanding the Question
The question addresses the current biological crisis known as the "Holocene Extinction" or the sixth mass extinction. It asks how the current rate of species loss compares to the five major natural mass extinction events that occurred in the geological past. Step 2: Key Formula or Approach
This is an environmental science and ecology question. It requires knowledge of the "Sixth Extinction" concept. The previous five extinctions were caused by natural disasters (volcanoes, asteroids, etc.). The current one is driven by human activity (anthropogenic causes). The primary difference is the rate of change. Step 3: Detailed Explanation
Historical Context: Throughout Earth's 4.5-billion-year history, mass extinctions have happened due to catastrophic natural events. The "Big Five" wiped out huge percentages of life, including the dinosaurs.
Current Scenario: We are currently losing species due to habitat destruction, pollution, climate change, and overexploitation.
Comparison of Rates: Research indicates that species are disappearing at a rate that is drastically higher than the natural background extinction rate. While previous mass extinctions happened over long geological periods, the current one is happening in a few centuries.
Magnitude: Ecologists estimate that the current species extinction rates are 100 to 1000 times faster than the rates that occurred in pre-human times (before human influence became dominant).
Step 4: Final Answer
The sixth mass extinction is characterized by a rate that is 100 to 1000 times higher than the natural background rate seen in previous episodes. Thus, option (C) is correct.