Why do exotic species pose a threat to an indigenous ecosystem such as in a Lake or an isolated island in the Andamans? 1. Such species compete with the local or native species for food. 2. They may be predators of local species. 3. Such species may cause diseases in native species. Select the correct answer code:

Why do exotic species pose a threat to an indigenous ecosystem such as in a Lake or an isolated island in the Andamans? 1. Such species compete with the local or native species for food. 2. They may be predators of local species. 3. Such species may cause diseases in native species. Select the correct answer code: Correct Answer 1, 2 and 3

The correct answer is 1, 2 and 3.

Key Points

• Exotic species introduced to new environments often reset the ecological conditions in that new habitat, threatening the species that exist there; this is the reason that they are also termed invasive species.
  • Such species compete with the local or native species for food
  • They may be predators of local species
  • Such species may cause diseases in native species
• Invasive species that are closely related to rare native species have the potential to hybridize with the native species; harmful effects of hybridization have led to a decline and even extinction of native species.
• Invasive species can change the food web in an ecosystem by destroying or replacing native food sources. The invasive species may provide little to no food value for wildlife.
• Lakes and islands are particularly vulnerable to extinction threats from introduced species.