Tracking Animals through e-DNA

• 08 Jan 2022

Why in News

According to some studies, DNA floating in the air (i.e. e-DNA) can boost biodiversity conservation efforts across the world.

Key Points

• About:
  
  • Researchers from two teams have independently shown that environmental DNA (e-DNA) can potentially identify and monitor terrestrial animals.
    
    • Animals shed DNA through their breath, saliva, fur or faeces into the environment and these samples are called e-DNA.
  • Airborne e-DNA sampling is a biomonitoring method that is rising in popularity among biologists and conservationists as it provides abundant information.
• Significance:
  
  • It can help understand the composition of animal communities and detect the spread of non-native species.
  • This method will work with the current techniques to monitor endangered species after some fine-tuning.
    
    • Typically, biologists observe animals in person or by picking up DNA from animals’ footprints or faeces, which demand extensive fieldwork.
    • Spotting animals can be challenging, especially if they inhabit inaccessible habitats.
  • It can aid in tracking long-distance migratory birds and other birds’ flying patterns. It can also capture DNA from smaller animals including insects.
    
    • Last year (2021), a proof-of-concept study used airborne e-DNA to monitor terrestrial insects.
  • As wildlife ecosystems become rapidly and extremely chaotic owing to the alarming effects of climate change, terrestrial biomonitoring techniques are expected to adapt and progress rapidly for accurate and timely monitoring.
• Related Initiatives:
  
  • Global EDNA Project: UNESCO launched the project to study the vulnerability of species to climate change at Marine World Heritage Sites in October 2021.

DNA

• DNA, short for deoxyribonucleic acid, is the hereditary material in organisms that contains the biological instructions for building and maintaining them.
• The chemical structure of DNA is the same for all organisms, but differences exist in the order of the DNA building blocks, known as base pairs.
• Unique sequences of base pairs, particularly repeating patterns, provide a means to identify species, populations, and even individuals.

e-DNA

• Environmental DNA (e-DNA) is nuclear or mitochondrial DNA that is released from an organism into the environment.
• Sources of eDNA include secreted feces, mucous, and gametes; shed skin and hair; and carcasses. eDNA can be detected in cellular or extracellular (dissolved DNA) form.
• In aquatic environments, eDNA is diluted and distributed by currents and other hydrological processes, but it only lasts about 7–21 days, depending on environmental conditions.
• Exposure to UVB radiation, acidity, heat, and endo- and exonucleases can degrade e-DNA.

Source: DTE