Causes of Biodiversity Loss — Prelims Strategy

Prelims Strategy

To excel in NEET questions on 'Causes of Biodiversity Loss', a multi-pronged strategy is essential. Firstly, thoroughly understand and memorize the 'Evil Quartet' (Habitat loss and fragmentation, Over-exploitation, Alien species invasions, Co-extinctions) as these are the core concepts.

For each cause, commit to memory the specific examples provided in the NCERT textbook, such as the Nile Perch in Lake Victoria, Parthenium, Lantana, Water Hyacinth, African Catfish for alien species, and the Steller's sea cow and Passenger Pigeon for over-exploitation.

Secondly, focus on the 'why' and 'how' – understand the mechanisms behind each cause. For instance, for habitat fragmentation, grasp the concepts of reduced population size, increased edge effect, and barriers to gene flow.

Thirdly, pay attention to the relative importance of each cause; NCERT explicitly states that habitat loss and fragmentation is the most important. Finally, practice identifying trap options in MCQs, which often involve misattributing an example to the wrong cause or presenting a consequence as a cause.

Regular revision of these examples and mechanisms will solidify your understanding and recall.