Prelims: Current events of national and international importance | Environment
Why in News?
Recent genomic studies on Aedes aegypti reveal that human movement, rapid urbanization, and regional transport networks are actively shaping the species' genetic structure and high gene flow across India.
Key Highlights of the Findings
- Aedes aegypti populations across different eco-climatic zones in India exhibit high genetic similarity despite long distances.
- Long-distance mixing is driven primarily by long-distance human transit (railways, highways, and logistics networks) passively transporting mosquitoes and their drought-resistant eggs across state borders.
- Unplanned urban growth, artificial water storage habits, and dense construction sites create abundant, micro-localized breeding grounds.
- This anthropophilic (human-preferring) niche buffers mosquito populations against local climate extremes, facilitating widespread interbreeding between urban and semi-urban lineages.
- Indiscriminate use of chemical vector control (like pyrethroid-based fogging and indoor sprays) has exerted strong selective pressure.
- This human-driven pressure accelerates the spread of specific knockdown resistance genetic mutations across distant populations.
Aedes aegypti
- Origin - Native to West Africa.
- The domestic lineage evolved a specialized preference for human blood and artificial water containers before spreading globally via international maritime and trade routes.
- Bionomics - Daytime biter, highly anthropophilic, and primarily breeds in clean, stagnant water held in artificial in and around domestic dwellings.
- Co-circulating Vectors- Works alongside Aedes albopictus (Asian tiger mosquito), which occupies more suburban/rural vegetation niches, complicating vector management.
Reference
The Hindu | Genetic diversity of dengue mosquitoes
