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Distribution: yearly

  • Assam to recognize Bathou Faith

    Why in the News?

    The Bodoland Territorial Region (BTR) government in Assam has officially included ‘Bathouism’ as an option in the religion column of key application forms, including admission forms, birth and death certificates.

    What is Bathouism?

    • Bathouism is the traditional faith of the Bodo people, primarily practiced in Assam and the foothills of Bhutan.
    • It is a nature-centric religion that worships Bathoubwrai, the supreme deity believed to govern the universe.
    • The central symbol of Bathouism is the Sijou plant (Euphorbia antiquorum), representing Bathoubwrai and planted in sacred enclosures (Bathou Thansali).
    • Bathou Puja is performed to seek divine blessings for prosperity, health, and well-being.
    • The Assam government has recently recognized Bathouism as a distinct faith, allowing its inclusion in official documents.

    Philosophy of Bathouism

    • Bathouism is based on five fundamental elements, known as Ba (five) Thou (deep thought), representing natural forces:
    1. Bar (Air) – Symbolizes breath, movement, and life force.
    2. San (Sun) – Represents light, energy, and warmth.
    3. Ha (Earth) – Stands for stability, fertility, and sustenance.
    4. Or (Fire) – Denotes transformation and purification.
    5. Okhrang (Sky) – Represents infinite wisdom and cosmic balance.
    • Bathoubwrai (Sibwrai) is considered almighty, omniscient, and eternal, beyond time and space. He is indestructible—fire cannot burn him, water cannot moisten him, air cannot dry him, and weapons cannot pierce him.
    • Bathouism promotes:
    1. Truthfulness, honesty, and righteousness.
    2. Respect for elders, ancestors, and nature.
    3. Peaceful coexistence and non-violence.
    4. Gratitude through rituals and pujas.
    • Bathou rituals involve five bamboo sticks symbolizing the five elements, with offerings of rice beer, milk, flowers, and incense.
    • Ancestral veneration and community harmony are integral aspects of the faith.

    PYQ:

    [2014] Which one of the following pairs does not form part of the six systems of Indian Philosophy?

    (a) Mimamsa and Vedanta

    (b) Nyaya and Vaisheshika

    (c) Lokayata and Kapalika

    (d) Sankhya and Yoga

     

  • SC stays Lokpal order on power over judges

    Why in the News?

    The Supreme Court recently halted a Lokpal order that sought to include High Court judges under its jurisdiction, calling the anti-corruption body’s interpretation “very disturbing.”

    Why did the Supreme Court stay the Lokpal order?

    • Violation of Judicial Independence (Article 50 & Article 121): The Supreme Court held that bringing High Court judges under Lokpal’s jurisdiction undermines judicial independence, which is a part of the Basic Structure Doctrine.
      • Article 50 mandates the separation of the judiciary from the executive, preventing interference in judicial functioning.
      • Article 121 prohibits Parliament from discussing the conduct of judges except in matters of impeachment, reinforcing judicial autonomy.
    • Judges Are Appointed Under the Constitution (Article 124 & Article 217): The Supreme Court rejected Lokpal’s argument that High Courts were created by British laws, emphasizing that all judges are appointed under the Constitution.
      • Article 124 establishes the Supreme Court, while Article 217 governs the appointment of High Court judges, ensuring their independence from executive control.
    • Judicial Oversight Is an Internal Process (Article 124(4) & Article 217(1)(b)): The Supreme Court reaffirmed that judicial misconduct should be handled internally, either through the in-house procedure or the impeachment process.
      • Article 124(4) (for Supreme Court judges) and Article 217(1)(b) (for High Court judges) provide for removal only through Parliamentary impeachment, making external investigations by the Lokpal unconstitutional.

    What is suo motu case? 

    Suo motu (Latin: on its own motion) refers to the Supreme Court or High Courts taking up a case on their own initiative, without a formal petition being filed.

    In which circumstances do courts in India exercise suo motu powers?

    • Constitutional Concerns (Separation of Powers, Judicial Independence): Courts intervene suo motu when an issue threatens constitutional principles like the separation of powers or judicial independence.
      • Example: In re: Article 370 of the Constitution (2023) – The Supreme Court took up the matter of abrogation of Article 370 to examine whether the Union government’s decision upheld constitutional principles.
    • Fundamental Rights Violations: Courts act suo motu when fundamental rights under Articles 14 (equality), 19 (freedom), and 21 (right to life) are violated.
      • Example: Suo Motu Writ Petition (Criminal) No.1 of 2020 – The Supreme Court intervened during COVID-19 migrant crisis, directing the government to provide food, shelter, and transport to stranded workers.
    • Public Interest or Institutional Integrity: Courts take suo motu cognizance to protect public interest and prevent harm to democratic institutions.
      • Example: Suo Motu Cognizance of Lakhimpur Kheri Violence (2021) – The Supreme Court intervened to monitor the UP government’s investigation into the killing of protesting farmers, ensuring transparency and accountability.

    Why did the Lokpal order bring High Court judges under its jurisdiction?

    • Interpretation of ‘Public Servants’ Under Lokpal Act: The Lokpal classified High Court judges as public servants under the Lokpal and Lokayuktas Act, 2013, making them subject to its jurisdiction.
    • Reliance on Section 14(1)(f) of the Lokpal Act: This section grants Lokpal jurisdiction over any body or authority established by an Act of Parliament.
      • The Lokpal argued that High Courts were established by British Parliamentary Acts (Indian High Courts Act, 1861 & Government of India Act, 1935), making them fall within this clause.
    • Distinction Between High Courts and Supreme Court: The Lokpal reasoned that Article 124 of the Constitution explicitly established the Supreme Court, but Article 214 only recognized High Courts, implying that High Courts were not directly created by the Constitution.
      • Based on this, the Lokpal ruled that Supreme Court judges were outside its jurisdiction, but High Court judges were not.
    • Lack of Explicit Exemption for Judges: The 2013 Lokpal Act does not explicitly exclude High Court judges from its jurisdiction, which the Lokpal interpreted as allowing it to investigate them.
    • Case-Specific Justification: The complaint involved a High Court judge allegedly influencing judicial decisions for personal benefit. The Lokpal argued that since the judge was serving in a High Court of a State reorganized by an Act of Parliament, it had jurisdiction over the matter.

    Way forward: 

    • Judicial Accountability Within Constitutional Framework: Strengthen in-house mechanisms for judicial oversight while ensuring compliance with constitutional provisions like Articles 124(4) and 217(1)(b), which mandate impeachment as the sole removal process for judges.
    • Clarify Lokpal’s Jurisdiction Through Legislative Review: Amend the Lokpal and Lokayuktas Act, 2013, to explicitly define its jurisdiction, ensuring it does not encroach upon judicial independence while maintaining transparency in the judiciary.

    Mains PYQ:

    Q Judicial Legislation is antithetical to the doctrine of separation of powers as envisaged in the Indian Constitution. In this context justify the filing of large number of public interest petitions praying for issuing guidelines to executive authorities. (UPSC IAS/2020)

  • What is Article 101(4)? 

    Why in the News?

    Amritpal Singh’s detention has raised concerns over his parliamentary position, as Article 101(4) states that an MP’s seat can be vacated after 60 consecutive absences without permission. He has missed 46 sittings so far.

    About Article 101(4) and its Feature

    • Article 101(4) states that if a Member of Parliament (MP) is absent from all meetings of the House for a period of 60 days, their seat may be declared vacant.
    • The 60-day period is counted continuously (excluding adjournments but including recess).
    • If the MP remains absent without prior permission from the House, the seat can be vacated under Article 101(4).
      • No MP has ever lost a seat under Article 101(4) in practice.
    • The House may grant condonation (excuse the absence) if a valid reason is provided.
    • This provision ensures active participation of MPs and prevents prolonged absenteeism.
    • If an MP does not attend any session of Lok Sabha or Rajya Sabha for 60 days without permission, the House can initiate proceedings to declare the seat vacant.

    Legal Options

    • Like past MPs, Amritpal can formally request permission to remain absent due to his incarceration.
    • Former MP from Uttar Pradesh Atul Rai received similar permission in 2023 while in jail.
    • The Lok Sabha must formally vote to declare his seat vacant, making disqualification unlikely unless actively pursued.

    PYQ:

    [2012] Regarding the office of the Lok Sabha speaker, consider the following statements:

    1. He/She holds the office during the pleasure of the President.
    2. He/She need not be a member of the House at the time of his/her election but has to become a member of the House within six months from the date of his/her election.
    3. If he/she intends to resign, the letter of his/her resignation has to be addressed to the Deputy Speaker.

    Which of the statements given above is/are correct?

    (a) 1 and 2 only
    (b) 3 only
    (c) 1, 2 and 3
    (d) None

     

  • Microsoft unveils ‘Majorana 1’ Chip for Quantum Computing

    Why in the News?

    Microsoft has unveiled Majorana 1, a groundbreaking quantum chip that introduces a more stable and scalable approach to quantum computing.

    What is Microsoft’s Majorana 1 Chip?

    • Majorana 1 is Microsoft’s latest quantum processor that introduces a new type of stable and scalable qubit based on Majorana fermions.
    • Microsoft believes that this breakthrough could enable practical quantum computing by 2027-29.
    • Majorana Fermions:
      • First theorized by Ettore Majorana in 1937.
      • Exotic particles that act as their own antiparticles.
      • Microsoft engineered them using topological conductors, making qubits more stable and resistant to errors.

    Features of Majorana 1 Chip:

    • Uses topological qubits, which require less error correction compared to traditional superconducting qubits.
    • More scalable, allowing the quantum chip to reach up to 1 million qubits in the future.
    • Built from indium arsenide-aluminum topo-conductors, unlike conventional silicon-based quantum chips.
    • Operates at near absolute zero temperature, tuned with magnetic fields to create a stable quantum environment.
    • Currently an 8-qubit chip, but designed with an architecture that supports significant expansion.

    What is Quantum Computing?

    • Quantum computing is a new approach to computation based on the principles of quantum mechanics that allows computers to process information exponentially faster than classical computers.
    • Unlike classical computers that use binary bits (0 or 1), quantum computers use qubits, which can exist in both 0 and 1 simultaneously (superposition).
    • Key Principles of Quantum Computing:
      • Superposition:  Qubits exist in multiple states at once.
      • Entanglement: –Qubits can be linked, meaning a change in one affects the other instantly.
      • Quantum Tunneling: Qubits can pass through energy barriers.
      • Quantum Interference:  Enhances correct probabilities while canceling out incorrect ones.
    • Quantum computers solve complex problems that are impossible for classical computers, such as simulating molecules, optimizing logistics, and advancing AI.

     

    PYQ:

    [2022] Which one of the following is the context in which the term “qubit” is mentioned?

    (a) Cloud Services
    (b) Quantum Computing
    (c) Visible Light Communication Technologies
    (d) Wireless Communication Technologies

     

  • NGT Report on Ganga Water Quality

    Why in the News?

    The National Green Tribunal (NGT) has raised concerns over the water quality of the Ganga at Triveni Sangam in Prayagraj, Uttar Pradesh. The river is failing to meet bathing standards due to high Biological Oxygen Demand (BOD) and faecal coliform contamination.

    Key Findings of the Ganga Water Quality Assessment at Triveni Sangam:

    • Water is unsafe for bathing as per Central Pollution Control Board (CPCB) standards.
    • BOD levels exceeded the permissible limit of 3 mg/L on multiple days in January 2025.
    • Government releasing 10,000-11,000 cusecs of fresh water to improve quality.
    • Faecal coliform levels (E. coli) far exceed safe limits due to sewage contamination.
    • Safe limit: 2,500 MPN/100 ml; Detected levels: 49,000 MPN/100 ml (Ganga) and 33,000 MPN/100 ml (Yamuna).

    What is Biological Oxygen Demand (BOD)?

    • BOD measures the amount of oxygen required by bacteria to break down organic matter in water.
    • Higher BOD levels indicate higher organic pollution, which can lead to oxygen depletion and aquatic life destruction.
    • Safe limit for bathing water is below 3 mg/L.
    • Excessive BOD levels suggest sewage, industrial waste, or decomposing organic matter contamination.
    • BOD levels above safe limits can cause waterborne diseases and disrupt aquatic ecosystems.

    PYQ:

    [2017] Biological Oxygen Demand (BOD) is a standard criterion for:

    (a) Measuring oxygen levels in blood

    (b) Computing oxygen levels in forest ecosystems

    (c) Pollution assay in aquatic ecosystems

    (d) Assessing oxygen levels in high-altitude regions

     

  • Why global sea ice cover has dipped to record low — what this means

    Why in the News?

    Between February 8 and 13, the total area of sea ice in the Arctic and Antarctic shrank to 15.76 million sq km, breaking the previous record low of 15.93 million sq km from early 2023, according to a BBC analysis of data from the US National Snow and Ice Data Center (NSIDC).

    What are the reasons for the record low?

    • Warm Air and Ocean Temperatures: Elevated air and sea temperatures have significantly contributed to the melting of both Arctic and Antarctic sea ice. Warmer conditions, particularly towards the end of summer, have led to increased melting rates, especially in the Antarctic region.
    • Wind Patterns: Changes in atmospheric dynamics, including stronger westerly winds associated with the Southern Annular Mode (SAM), have disrupted sea ice formation and stability. In the Antarctic, these winds can break apart ice more easily due to its thinner and more mobile nature compared to the thicker Arctic ice.
    • Delayed Freezing: In the Arctic, a delayed freezing process around regions like Hudson Bay has occurred due to unusually warm ocean temperatures, preventing the formation of new ice during winter.
    • Increased Freshwater Input: The melting of glaciers and ice shelves adds freshwater to the oceans, which can alter ocean stratification and impact sea ice formation. While freshwater can initially encourage sea ice growth in some contexts, it also leads to changes that may ultimately reduce overall sea ice extent.
    • Feedback Mechanisms: The loss of sea ice creates feedback loops that further exacerbate warming. As less ice remains to reflect sunlight, more solar radiation is absorbed by the ocean, leading to increased temperatures and further melting of ice.

    What does “dip” mean?

    • In the context of the recent report on sea ice, the term “dip” refers to a significant decrease or reduction in the extent of sea ice coverage. Specifically, it denotes the record low measurement of combined Arctic and Antarctic sea ice, which fell to 15.76 million square kilometres, marking a decline from previous levels.
    • This “dip” highlights the alarming trend of diminishing sea ice, which is crucial for regulating global temperatures and maintaining ecological balance in polar regions.

    What could be its impact?

    • Accelerated Global Warming: Less sea ice means more ocean water is exposed to sunlight, absorbing heat instead of reflecting it. Example: The Arctic is warming nearly four times faster than the global average, leading to extreme weather patterns worldwide.
    • Disruptions in Ocean Currents: Melting sea ice releases freshwater into the ocean, reducing salinity and slowing down deep-water circulation. Example: The Atlantic Meridional Overturning Circulation (AMOC), which influences global climate patterns, is weakening due to increased freshwater from melting Arctic ice.
    • Threat to Marine Ecosystems: Sea ice loss affects marine species dependent on stable ice conditions for survival. Example: Polar bears rely on sea ice for hunting seals. As ice declines, they face starvation and habitat loss. Similarly, krill populations in Antarctica, a key food source for whales and penguins, are declining due to changing ice conditions.
    • More Extreme Weather Events: Changes in polar ice influence atmospheric circulation, leading to unpredictable weather. Example: The weakening of the polar vortex due to Arctic warming has been linked to severe cold waves in North America and Europe, such as the Texas winter storm in 2021.
    • Coastal and Infrastructure Damage: Rising temperatures due to ice melt contribute to permafrost thawing, which destabilizes infrastructure in polar regions. Example: In Siberia, Russia, thawing permafrost has caused buildings and roads to collapse, posing a major economic and environmental challenge.

    What measures have been taken at the international level?

    • International Year of Glaciers’ Preservation (2025): The World Meteorological Organization (WMO) and UNESCO have declared 2025 as the International Year of Glaciers’ Preservation. This initiative aims to raise awareness about the importance of glaciers and ice sheets, which store a significant portion of the world’s freshwater, and to promote actions to mitigate their melting.
    • Global Cryosphere Watch: The WMO’s Global Cryosphere Watch network, which includes scientists from the Intergovernmental Panel on Climate Change (IPCC), has been actively monitoring and reporting on cryosphere changes. Their findings highlight alarming trends in ice loss and emphasize the need for immediate action to address these issues.
    • Collaborative Research Initiatives: Various international scientific collaborations are underway to study and model the impacts of climate change on sea ice. These efforts involve researchers from multiple countries working together to gather data, analyze trends, and develop strategies for adaptation and mitigation.
    • Climate Action Frameworks: Global climate agreements, such as the Paris Agreement, encourage countries to commit to reducing greenhouse gas emissions, which are a primary driver of climate change affecting sea ice.
    • Public Awareness Campaigns: International organizations are engaging in campaigns to educate the public about the significance of sea ice and glaciers in regulating global climate systems.

    Way forward: 

    • Strengthening Climate Mitigation Efforts: Nations must enhance commitments under the Paris Agreement by accelerating renewable energy adoption, reducing greenhouse gas emissions, and implementing carbon pricing mechanisms to curb global warming.
    • Enhancing Polar and Oceanic Monitoring: Strengthen international collaboration for real-time satellite monitoring, expand scientific research on polar ice dynamics, and develop adaptive strategies to protect vulnerable ecosystems and coastal communities.

    Mains PYQ:

    Q How do the melting of the Arctic ice and glaciers of the Antarctic differently affect the weather patterns and human activities on the Earth? Explain. (UPSC IAS/2021)

  • [pib] Periodic Labour Force Survey (PLFS) Quarterly Bulletin

    Why in the News?

    The latest edition of PLFS report (October-December 2024) has highlighted key labour market indicators.

    plfs

    About Periodic Labour Force Survey (PLFS)

    • The PLFS is conducted by the National Statistical Office (NSO), Ministry of Statistics and Programme Implementation (MoSPI) to assess employment and unemployment trends in India.
    • Launched in April 2017, PLFS provides quarterly estimates for urban areas and annual estimates for both rural and urban areas.
    • Key Indicators:
    1. Labour Force Participation Rate (LFPR): Percentage of people working or seeking jobs.
    2. Worker Population Ratio (WPR): Percentage of people employed.
    3. Unemployment Rate (UR): Percentage of job seekers unable to find employment.
    4. Current Weekly Status (CWS): Employment status based on work done in the last 7 days.
    • Survey Methodology:
      • Urban Areas: Rotational Panel Sampling (each household surveyed four times).
      • Data Collected (Oct-Dec 2024): 5,742 urban units surveyed, covering 1,70,487 individuals across 45,074 households.
      • Publication: Quarterly Bulletins for urban areas, Annual Reports for rural and urban regions.

    Key Highlights of PLFS (Oct-Dec 2024)

    • Labour Force Participation Rate (LFPR): 50.4% (↑ from 49.9% in 2023).
      • Male LFPR: 75.4% (↑ from 74.1% in 2023).
      • Female LFPR: 25.2% (↑ from 25.0% in 2023).
    • Worker Population Ratio (WPR): 47.2% (↑ from 46.6% in 2023).
      • Male WPR: 70.9% (↑ from 69.8% in 2023).
      • Female WPR: 23.2% (↑ from 22.9% in 2023).
    • Unemployment Rate (UR): 6.4% (↓ from 6.5% in 2023).
      • Male UR: 5.8% (unchanged).
      • Female UR: 8.1% (↓ from 8.6% in 2023).

    PYQ:

    [2023] Most of the unemployment in India is structural in nature. Examine the methodology adopted to compute unemployment in the country and suggest improvements.

    [2013] Disguised unemployment generally means:

    (a) large number of people remain unemployed

    (b) alternative employment is not available

    (c) marginal productivity of labour is zero

    (d) productivity of workers is low

     

  • New study challenges the age of Saturn’s Rings

    Why in the News?

    A new study has challenged previous assumptions, suggesting that Saturn’s rings could be as old as the Solar System (~4.5 billion years old).

    New study challenges the age of Saturn’s Rings

    About Saturn and Its Rings

    • Saturn, the sixth planet from the Sun, is famous for its iconic ring system, made up of billions of ice and rock particles ranging in size from tiny grains to massive chunks.
    • It is primarily composed of water ice (95%), with some dust and rocky debris.
    • The rings are divided into seven main sections (A to G), with gaps like the Cassini Division.
    • Scientists have debated whether the rings formed with Saturn (~4.5 billion years ago) or if they are only 100-400 million years old.
    • Over time, tiny space rocks should darken the rings, yet they remain surprisingly bright.

    Key Findings of the Study:

    • Earlier estimates, based on Cassini data, suggested the rings were 100-400 million years old because they looked clean and bright.
    • The new study suggests that micrometeoroid collisions remove dust efficiently, preventing the rings from darkening over time.
    • High-speed micrometeoroid impacts (~108,000 km/h) cause dust to vaporize, rather than accumulate.
    • The vaporized dust either escapes Saturn’s gravity, falls into the planet’s atmosphere, or gets ejected into space, keeping the rings pristine.
    • 100 million years ago, the Solar System was stable, making ring formation unlikely.
    • 4 billion years ago, the Solar System was chaotic, increasing the chances of violent planetary collisions that could have formed Saturn’s rings.

    Various Missions to Saturn

    Saturn has been explored by multiple spacecraft, each providing valuable insights into its rings, atmosphere, and moons.

    1. Pioneer 11 (1979)

    • First spacecraft to fly past Saturn, capturing basic images.

    2. Voyager 1 & Voyager 2 (1980-1981)

    • Discovered new moons and ring structures.
    • Provided detailed images of Saturn’s rings.

    3. Cassini-Huygens (1997-2017)

    • A NASA-ESA-ASI mission that orbited Saturn for 13 years.
    • Key discoveries:
      • Confirmed liquid oceans on Enceladus.
      • Found methane lakes on Titan.
      • Observed Saturn’s rings losing material into the planet’s atmosphere.

     

    PYQ:

    [2009] Which one of the following planets has largest number of natural satellites or moons?

    (a) Jupiter
    (b) Mars
    (c) Saturn
    (d) Venus

     

  • Iron Age in India

    Why in the News?

    Tamil Nadu CM recently proclaimed that the Iron Age began on Tamil soil over 5,300 years ago (4th millennium BCE), based on findings from Mayiladumparai, Sivagalai, Adichanallur, and Kilnamandi.

    Iron Age in India

    • The Iron Age in India was initially thought to have begun around 700-600 BCE.
    • Radiocarbon dating pushed the timeline back to 1800 BCE, with evidence of iron smelting found in Central Ganga Plain and Eastern Vindhyas.
    • Recent discoveries in Tamil Nadu suggest that iron metallurgy was established in South India as early as 3300 BCE.

    Notable Iron Age Sites in India:

    1. Central and Northern India
    • Raja Nala-ka-tila (UP): Iron tools and slag found in pre-NBP (Northern Black Polished) deposits (1400–800 BCE).
    • Malhar (Chandauli, UP): Furnaces and iron slag indicate a major iron metallurgy center (1200 BCE).
    • Dadupur (UP): Large-scale iron smelting evidence dating back to 1000 BCE.
    • Hastinapur (UP): Iron tools associated with the Painted Grey Ware (PGW) culture (1000 BCE).
    • Takshashila (Punjab, Pakistan): Iron tools found in Gandhara settlements (800 BCE).
    1. Western and Central India
    • Ahar (Rajasthan): Chalcolithic culture (2500–1700 BCE) showed early evidence of iron artifacts.
    • Naikund (Vidarbha, Maharashtra): Discovery of an iron smelting furnace (1000 BCE).
    • Mahurjhari (Nagpur, Maharashtra): Horse ornaments made of copper with iron knobs (800 BCE).
    1. South India
    • Paiyampalli (Tamil Nadu): Large-scale iron smelting and slag deposits (1200 BCE).
    • Adichanallur (Tamil Nadu): Iron tools and burial urns linked to Megalithic culture (1000 BCE).
    • Mayiladumparai (Tamil Nadu): Recent findings date iron usage to 3300 BCE, making it one of the oldest sites of iron metallurgy in India.
    • Sivagalai (Tamil Nadu): Iron artifacts and slag deposits, indicating early smelting practices (1100 BCE).

    Iron Age in Tamil Nadu: New Discoveries

    • Earlier studies in Mayiladumparai Excavation (2022) suggested that the Iron Age began 4,200 years ago (3rd millennium BCE).
    • This timeline coincides with the Copper/Bronze Age in North India, indicating a technological divergence between the regions.
    • The latest State Archaeology Department’s report, “Antiquity of Iron: Recent Radiometric Dates from Tamil Nadu”, confirms that Iron smelting began as early as 3,345 BCE – 2,953 BCE.
    • Limited availability of copper ores in South India might have led to the early adoption of iron technology.
    • Excavations in Sivagalai, Adichanallur, Kilnamandi, and Mayiladumparai indicate that the Iron Age in Tamil Nadu predates much of North India.

    PYQ:

    [2017] With reference to the difference between the culture of Rigvedic Aryans and Indus Valley people, which of the following statements is/are correct?

    1. Rigvedic Aryans used the coat of mail and helmet in warfare whereas the people of Indus Valley Civilization did not leave any evidence of using them.
    2. Rigvedic Aryans knew gold, silver and copper whereas Indus Valley people knew only copper and iron.
    3. Rigvedic Aryans had domesticated the horse whereas there is no evidence of Indus Valley people having been aware of this animal.

    Select the correct answer using the code given below:

    (a) 1 only

    (b) 2 and 3 only

    (c) 1 and 3 only

    (d) 1, 2 and 3

     

  • Nocturnal Bull Ants Navigate Using Polarized Moonlight

    Why in the News?

    Scientists at Macquarie University, Sydney, have discovered that two species of nocturnal bull ants (Myrmecia pyriformis and Myrmecia midas) rely on polarised moonlight for navigation.

    Nocturnal Bull Ants Navigate Using Polarized Moonlight

    What is Polarised Moonlight?  

    • Polarised moonlight refers to moonlight that has undergone scattering in Earth’s atmosphere, causing its waves to oscillate in a specific direction.
    • Unlike direct moonlight, which is unpolarised, the light that scatters in the sky becomes linearly polarised, meaning its electric field aligns in a fixed plane.
    • The moon emits unpolarised light, but when it interacts with air molecules and dust particles in the atmosphere, it scatters and becomes polarised.
    • The intensity of polarised moonlight is much lower than polarised sunlight, making it harder for most animals to detect.
    • The pattern of polarisation in moonlight remains stable, allowing nocturnal animals to use it as a reliable navigation tool.
    • Why is it Important for Navigation?
      • Many nocturnal animals, including bull ants (Myrmecia pyriformis and Myrmecia midas), rely on celestial cues to orient themselves.
      • Unlike the moon’s direct position, which changes with phases and cloud cover, the polarisation pattern remains detectable throughout the night.
      • This enables ants to navigate effectively even under crescent or waning moons, where light intensity is significantly lower.

    E-Vector Pattern and Ant Navigation

    • Polarised moonlight forms a distinct pattern in the sky, known as the E-vector pattern.
    • This pattern shifts based on the moon’s position, but its orientation remains stable, allowing insects like ants to use it as a natural compass.
    • The E-vector pattern aligns at 90° to the moon’s direct light, creating a predictable navigation reference.
    • How do Bull Ants use it?
      • Ants detect the E-vector pattern in the night sky using their specialised compound eyes, which are sensitive to polarised light.
      • Even in dim conditions, they adjust their movements according to the orientation of polarised moonlight.
      • Researchers found that when the E-vector was artificially rotated, the ants changed their paths accordingly, confirming that they rely on this pattern.
      • When the moonlight disappeared (during a new moon phase), the ants struggled to navigate, further proving their dependence on polarised lunar light.