×

UPSC Courses

DNA banner

DAILY NEWS ANALYSIS

  • 11 December, 2023

  • 2 Min Read

Otolith Rings 

A new study published in ‘Nature’, tried to predict the effects of climate change on the physiological performance and distribution of organisms by studying the Otoliths.

Otolith – They are small, white bio-mineralized ear stones in the head.Small calcium carbonate crystals are accumulated every day as very thin layers over a tiny core, and this forms an otolith.

  • They are found in all fishes other than sharks, rays and lampreys but their shape and morphology is unique to each fish species.
  • It contributes to both hearing and vestibular function in fish.

Significance – When the fish dies the otoliths are preserved, separated from the decomposed fish body, and buried in the sediments of the sea floor unaffected for thousands of years.It records the age and growth of a fish from the date of hatch to the time of death and also reveals about fish’s health.

    • Oxygen isotopes – It indicate the temperature the fish experienced when it was alive.
    • Carbon isotopes – It reveal how quickly food was converted into energy.

Otoliths relevance in climate change - Animals’ energy needs shift with temperature and studying the otoliths can help us predict which animals are most at risk from rising temperatures.

Atlantic bluefin tuna in warmer waters had lower metabolic rates, showing that their bodies were unable to keep up with the energy costs of living in temperatures over 28°C.

Source:


India–Azerbaijan

A year after tensions arising from Operation Sindoor, India and Azerbaijan have taken steps to restore and normalise bilateral relations. The 6th round of Foreign Office Consultations, held in Baku, marked the first such engagement since 2022, signaling renewed diplomatic momentum. Recent Diplomatic Engagement During the consultations, bo

India–Australia Economic Cooperation and Trade Agreem

The India–Australia Economic Cooperation and Trade Agreement has completed four years since its signing. Both countries now aim to build on this progress through strengthened collaboration and ambitious targets, including reaching AUD 100 billion in bilateral trade by 2030. What is the India–Australia Economic Cooperation and Tra

ADR Report on Political Funding

A recent report by the Association for Democratic Reforms (ADR) analyses donations of ?20,000 or more declared to the Election Commission of India (ECI) by national political parties for FY 2024–25, highlighting transparency and accountability in political financing. Key Findings Massive Funding Surge Total donations to nationa

Maritime Chokepoints

Maritime chokepoints are narrow channels along global shipping routes where maritime traffic is concentrated. These points are geopolitically and economically critical, as they handle a large proportion of global trade, especially energy shipments. Current Relevance Over two-thirds of seaborne energy trade passes through a handful o

US-Israel-Iran War

Following the launch of Operation Epic Fury (U.S.) and Operation Roaring Lion (Israel), the geopolitical landscape has shifted fundamentally with the confirmed death of Iran’s Supreme Leader, Ayatollah Ali Khamenei.Iran retaliated through Operation True Promise 4, launching missile attacks against Israel and nearby Gulf states. The escala

DNA

05 Apr,2026

Toppers

Search By Date

Newsletter Subscription
SMS Alerts

Important Links

UPSC GS Mains Crash Course - RAW