The Palghat Gap is a rift in the Western Ghats

The Palghat (Palakkad) Gap, a key corridor in India’s Western Ghats, is discussed in this article. It tells us about the geological genesis of the gap.

What exactly is the Palghat Gap?

  • The Palghat Gap is a 40-kilometer-long corridor in the Western Ghats famed for its steep hills that serves as a doorway to Kerala.
  • It is a vital link for roads and trains between Coimbatore and Palakkad.
  • The Palghat Gap is crossed by the Bharathappuzha River.
  • The vegetation in the gap is described as dry evergreen forest, as opposed to the Western Ghats’ tropical rainforests.
  • The Palghat Gap marks a unique split in the region’s flora and fauna.

Geological origin of the Palghat Gap

  • The Palghat Gap is a geological shear zone running from east to west.
  • Shear zones are weak areas in the Earth’s crust that cause tremors in the Coimbatore area on occasion.
  • The Palghat Gap formed when the continental shelf changed following the separation of Australia and Africa from the Gondwana landmass.
  • India and Madagascar were once connected until volcanic activity caused their separation, with a similar gap in Madagascar known as the Ranotsara Gap.

Ancient history and biogeographic differences

  • The biogeographic differences in species found north and south of the Palghat Gap could be linked to an old river or a sea intrusion in the distant past.
  • Elephant populations on the Nilgiris side of the gap have mitochondrial DNA that differs from elephant populations in the Anamalai and Periyar sanctuaries.
  • DNA research of the White-bellied Shortwing, an endemic bird species, reveals population divergence in the Nilgiris and Anamalai regions.

South of the Palghat Gap, biodiversity

  • The southern Western Ghats region, south of the Palghat Gap, has a high species richness and phylogenetic diversity.
  • A recent study found over 450 tree species, including 130 million-year-old species like Magnolia champaca.
  • The southern Western Ghats’ warm temperature and moist air support a varied spectrum of species, making it an island haven throughout ice ages and droughts.
  • In comparison to the northern part, the southern Western Ghats receive more equally distributed rainfall throughout the year.
And get notified everytime we publish a new blog post.