Q. 'Aerial metagenomics' best refers to which one of the following situations? (UPSC Prelims 2023)
Answer:
Collecting DNA samples from air in a habitat at one go
Notes: The correct answer is
[A] Collecting DNA samples from air in a habitat at one go. Aerial metagenomics is an emerging scientific field that focuses on studying the genetic material present in the atmosphere.
- Definition: Metagenomics is the study of genetic material recovered directly from environmental samples. When applied to the air, it involves capturing environmental DNA (eDNA)—microscopic fragments of DNA shed by organisms (bacteria, fungi, insects, plants, and even mammals) into the surrounding air.
- Mechanism: Scientists use high-efficiency air filters or specialized vacuum-like devices to suck in large volumes of air. The biological particles trapped on these filters are then sequenced using Next-Generation Sequencing (NGS) to identify the entire range of biodiversity in that specific habitat without having to physically capture or see the animals.
- Applications: This method is revolutionary for biodiversity monitoring, especially in dense forests or inaccessible terrains. It allows researchers to track endangered species, detect invasive pathogens, and monitor the health of an ecosystem by simply "sampling the breeze."
- Distinction: Unlike traditional wildlife surveys that rely on sightings or camera traps, aerial metagenomics provides a "genetic snapshot" of the entire community—from microscopic microbes to large vertebrates—at a single point in time.