Question 10 from UPSC CSE 2014 - Geography

Question

Which of the following phenomena might have influenced the evolution of organisms?
1. Continental drift
2. Glacial cycles
Select the correct answer using the code given below.

IASCODEX · Accepted Answer

Correct Option: C. Both 1 and 2

Strategy: Identify large-scale natural processes that influence evolution. Continental drift isolates populations, leading to speciation. Glacial cycles alter climates and habitats, causing migrations and extinctions. Both processes are significant evolutionary drivers, confirming the validity of both statements.

Key Info: **Continental Drift**
- Refers to the movement of Earth's continents over geological time due to plate tectonics.
- This process leads to the physical separation of landmasses, which isolates species populations and drives allopatric speciation.
- An example is the breakup of Pangaea, which resulted in the independent evolution of fauna in Africa, South America, and Australia.

**Glacial Cycles**
- Part of Quaternary climate fluctuations (Ice Ages), involving repeated advances and retreats of ice sheets.
- These dramatic environmental changes cause shifts in habitat, species dispersal, population bottlenecks, and extinctions.
- Many modern species, such as the woolly mammoth, have evolutionary histories shaped by these cycles, which also influence the current distribution of flora and fauna in Europe and North America.

Both continental drift and glacial cycles are major abiotic factors in macroevolutionary patterns, influencing biodiversity and the adaptation of organisms.

IASCODEX · Answer

Option A: 1 only

IASCODEX · Answer

Option B: 2 only

IASCODEX · Answer

Option D: Neither 1 nor 2

Which of the following phenomena might have influenced the evolution of organisms? Continental drift Glacial cycles Select the correct answer using the code given below.

Which of the following phenomena might have influenced the evolution of organisms?

Continental drift

Glacial cycles
Select the correct answer using the code given below.