The Wallace Line, a term recently seen in the news, is defined as:

The correct answer is option 4.

In News

• The Wallace Line was highlighted in recent discussions on biodiversity and species distribution, as researchers continue to explore why certain species are found on one side of the line but not the other.

Key Points

• The Wallace Line is an imaginary boundary running through the Malay Archipelago, first proposed by Alfred Russel Wallace in the 19th century.
• It separates the fauna of Asia and Australia, explaining why species like tigers and orangutans are found in Asia, while kangaroos and cockatoos are found in Australia.
• The distinct biodiversity on either side is due to historical continental drift, ocean currents, and climatic differences, which have shaped species migration patterns.
  • Hence, option 4 is correct.
• Sulawesi is an exception, where species from both sides coexist, adding complexity to the biogeography of the region.
• The Wallace Line is not a fixed boundary but a conceptual tool used in biogeography and evolutionary studies.