IAS Gyan

Daily News Analysis

Lesser Sunda Islands

5th July, 2024 Geography

Lesser Sunda Islands


Disclaimer: Copyright infringement not intended.

Context:  New Species of Bird Discovered on Lesser Sunda Islands


The discovery

  • A team of scientists from the Swedish Museum of Natural History and elsewhere has described a new species of nightjar living in the tropical forests of Timor and Wetar, Lesser Sunda Islands.


  • Nightjars are medium-sized nocturnal instectivorous birds in the family Caprimulgidae and the order Caprimulgiformes.

  • These birds are found all around the world, with the exception of Antarctica, and certain island groups such as the Seychelles.


  • Characterized by long wings, short legs, and very short bills, nightjars take flying insects on the wing, usually at night.
  • During the day, they sleep on the ground or perched, usually lengthwise, on a branch.

Lesser Sunda Islans

  • The Lesser Sunda Islands, also now known as Nusa Tenggara Islands, are an archipelago in Maritime Southeast Asia.
  • It is located to the east of Java and to the north of Western Australia.
  • The main Lesser Sunda Islands are, from west to east: Bali, Lombok, Sumbawa, Flores, Sumba, Savu, Rote, Timor, Atauro, Alor archipelago, Barat Daya Islands, and Tanimbar Islands.
  • Together with the Greater Sunda Islands to the west, they make up the Sunda Islands.
  • The islands are part of a volcanic arc, the Sunda Arc, formed by subduction along the Sunda Trench in the Java Sea.


  • The northern archipelago began to be formed during the Pliocene, about 15 million years ago, as a result of the collision between the Australian and the Asian plates.
  • The Lesser Sunda Islands consist of two geologically distinct archipelagos.
  • The northern archipelago, which includes Bali, Lombok, Sumbawa, Flores and Wetar, is volcanic in origin. Mount Rinjani on Lombok, are still active while others, such as Ilikedeka on Flores, are extinct.
  • The islands of the southern archipelago, including Sumba, Timor and Babar, are non-volcanic and appear to belong to the Australian plate.


Six ecoregions:

  • The Eastern Java-Bali rain forests and Eastern Java-Bali montane rain forests cover Bali.
  • The Lesser Sundas deciduous forests include the northern chain of islands, from Lombok and Sumbawa east to Flores and Alor.
  • The Sumba deciduous forests ecoregion includes Sumba.
  • The Timor and Wetar deciduous forests ecoregion includes Timor, Wetar, Rote, and Savu.
  • Banda Sea Islands moist deciduous forests ecoregion includes the Barat Daya Islands (except for Wetar), the Tanimbar Islands, and the Kai Islands.


Wikipedia, ScienceNews.


Q. Lesser Sunda Archipelago are formed due to the collision of which of the following plates?

A. Indian and Eurasian plate

B. Eurasian Plate and Australian plate

C. Pacific and Eurasian Plate

D. African and Eurasian Plate

Answer B