PYQ Relevance:
Q) How far are India’s internal security challenges linked with border management particularly in view of the long porous borders with most countries of South Asia and Myanmar? (2013)
Q) If a particular area is brought under the Fifth Schedule of the Constitution of India, which one of the following statements best reflects the consequence of it? (CSP 2022)
(a) This would prevent the transfer of land of tribal people to non-tribal people.
(b) This would create a local self-governing body in that area.
(c) This would convert that area into a Union Territory.
(d) The State having such areas would be declared a Special Category State. |
Mentor’s Comment: UPSC mains have always focused on internal security challenges linked with border management (2013), and Fifth Schedule (2022).
The India-Myanmar borderlands lack reliable data despite ongoing conflicts and crises. In Manipur, restricted access and security issues make it hard to document humanitarian needs. Misinformation worsens the situation. Around 58,000 people live in relief camps, while 12,000 fled to Mizoram and 7,000 to Nagaland, Assam, and Meghalaya. Data collection remains fragmented.
Today’s editorial discusses issues related to Manipur, which are relevant for GS Paper 3 (Mains) under the Security section.
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Let’s learn!
Why in the News?
The Manipur conflict is complex, and security issues make it hard to access certain areas leads to major gaps in tracking humanitarian needs.
How has the complexity of the conflict contributed to significant gaps in documenting humanitarian needs?
- Restricted Access and Security Concerns: The conflict’s complexity leads to restricted access for humanitarian organizations and data collectors due to security risks. Example: Adverse security conditions hinder the ability to thoroughly assess needs in certain areas.
- Breakdown of Information Chains: The physical and social separation of communities (like the Meitei and Kuki-Zomi) disrupts the flow of accurate information. Example: The separation makes it difficult to get a comprehensive understanding of the needs of both communities, as information does not flow freely between them.
- Unaccounted Populations: Official counts often only consider those in registered relief camps, overlooking unregistered individuals living with relatives, in temporary shelters, or displaced across multiple locations. Example: Many individuals displaced outside of registered camps or those who have left the State entirely are not included in official estimates, leading to underreporting.
- Altered Healthcare Access and Documentation: The conflict changes how people seek medical care, especially in conflicted regions, making it difficult to track health-related issues. Example: Residents of Kuki-Zomi-dominated hill districts can no longer easily access major hospitals in Imphal, leading to indirect routes and potentially undocumented health crises.
- Misinformation and Disinformation: The spread of inaccurate information clouds the true picture, making it difficult to form an empirical understanding of the conflict’s impact. Example: The text mentions that misinformation and disinformation cloud an empirical understanding of the conflict.
Why do the India-Myanmar borderlands remain a data-deficient region despite their long history of armed conflict, displacement, and humanitarian crises?
- Challenging Geography: The region’s complex topography, characterized by rugged mountains and dense forests, complicates access for data collection efforts. For example, the difficult terrain has hindered the effective implementation of border initiatives such as fencing, which has faced significant logistical challenges over the years.
- Inadequate Infrastructure: There is a lack of basic infrastructure, including roads and communication networks, which impedes the movement of researchers and humanitarian workers.
- The Moreh Integrated Check Post (ICP) in Manipur, intended to facilitate trade and connectivity, has experienced slow construction and inadequate facilities, reflecting broader infrastructural deficiencies in the region.
- Political Sensitivities: The presence of various insurgent groups and ongoing conflicts creates a volatile environment that discourages data collection. Security concerns often prevent researchers and NGOs from engaging with local communities to gather necessary information on humanitarian needs.
- Shared Ethnic Ties and Cross-Border Dynamics: The interconnectedness of ethnic communities across the border complicates the situation further. Policies such as the cancellation of the Free Regime Movement (FMR) agreement have disrupted traditional social networks, making it difficult to assess the socio-economic conditions on both sides effectively.
- Restricted Access for Humanitarian Organizations: Government-imposed restrictions and logistical challenges prevent humanitarian agencies from collecting and reporting crucial data.
- Example: After Myanmar’s 2021 military coup, aid organizations faced severe restrictions in conflict-hit areas like the Sagaing Region, resulting in major data gaps on displacement and food insecurity.
Why does Manipur need a shift towards ‘greater common good’ politics?
- Ethnic Divisions and Communal Tensions: The conflict between the Meitei and Kuki-Zomi communities has created deep mistrust and segregation, making governance difficult. A politics of “greater common good” would prioritize reconciliation and collective welfare over ethnic identity-based politics.
- Humanitarian Crisis and Governance Failures: Prolonged displacement, lack of adequate relief measures, and deteriorating healthcare require governance focused on inclusive development rather than ethnic-based power struggles.
- Example: Over 58,000 displaced individuals are still in relief camps, struggling with food, water, and medical shortages due to lack of coordinated efforts.
- Economic and Social Stability: Manipur’s economic potential is hindered by violence, blockades, and an unstable law-and-order situation. A governance approach focused on the “greater common good” would foster investment, economic recovery, and social stability.
What are the steps taken by the Indian Government?
- Imposition of President’s Rule: On February 13, 2025, Manipur was placed under President’s Rule following the resignation of Chief Minister. This decision was made due to nearly two years of ethnic violence and political turmoil that had resulted in over 250 deaths and widespread unrest.
- Suspension of the State Assembly: The state assembly has been put under suspended animation, which means it will not function until the situation stabilizes. This is the 11th instance of President’s Rule being imposed in Manipur since its statehood.
- Security Measures: The central government has directed security forces to take all necessary steps to restore order in Manipur. This includes deploying additional military and paramilitary forces to manage the fragile security situation, which has seen recent escalations in violence.
- Appointment of a Security Advisor: Following the invocation of Article 355 of the Indian Constitution, a security advisor was appointed to assist the Chief Minister in managing law and order.
- Investigation into Violence: The Ministry of Home Affairs has handed over important cases related to the violence to the National Investigation Agency (NIA) for effective investigation, indicating a commitment to addressing the root causes of the unrest.
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Way forward:
- Inclusive Dialogue and Reconciliation: Establish a truth and reconciliation commission involving all ethnic communities to foster trust, address grievances, and create a roadmap for long-term peace and stability.
- Sustainable Development and Governance Reforms: Focus on infrastructure development, livelihood generation, and transparent governance to ensure equitable growth, reduce ethnic tensions, and rebuild public confidence in state institutions.
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Note4Students
From UPSC perspective, the following things are important :
Mains level: Telecom sector;
Why in the News?
The Coalition for Disaster Resilient Infrastructure (CDRI), a global organization launched by Prime Minister Narendra Modi in 2019, recently released a report assessing how well Indian telecom networks can handle disasters.
What does the Coalition for Disaster Resilient Infrastructure report state?
- Multi-Hazard Risk Assessment: The report conducted a comprehensive risk assessment across 0.77 million telecom towers, evaluating vulnerabilities to various disasters such as floods, cyclones, and earthquakes, which informs infrastructure planning and resilience strategies.
- Disaster Risk and Resilience Index: A new index was developed to assess the vulnerability of telecom infrastructure based on factors like disaster intensity and frequency, enabling targeted risk management efforts.
- Technical and Governance Enhancements: Recommendations include improving technical planning and design of telecom infrastructure to withstand disasters, as well as integrating disaster resilience into sectoral policies through risk-informed governance.
- Financial Instruments and Collaboration: The report advocates for establishing risk-sharing mechanisms to protect telecom operators financially, alongside promoting cross-sectoral collaboration for coordinated disaster response efforts.
- Last-Mile Connectivity and Digital Solutions: Emphasizing the importance of inclusive emergency responses, the report calls for enhancing last-mile connectivity and leveraging digital solutions to ensure rapid service restoration during crises.
Why do telecom networks face elevated risks in coastal regions in times of disaster and calamity?
- High Exposure to Cyclones & Storm Surges: Coastal areas frequently experience high-speed winds and storm surges, which can damage telecom towers and disrupt communication. Example: During Cyclone Amphan (2020), telecom networks in West Bengal and Odisha were severely impacted due to tower collapses and flooding.
- Vulnerability of Undersea Cable Landing Stations: Undersea cables connect India to global internet infrastructure, and their landing stations are located in coastal regions. Damage to these stations can cause widespread internet outages. Example: In 2023, a disruption in undersea cables near the Red Sea affected internet speeds in South Asia, including India.
- Power Failures Due to Flooding & Infrastructure Damage: Coastal disasters often lead to massive power outages, affecting telecom towers and network operating centres that rely on continuous electricity. Example: During Cyclone Tauktae (2021), heavy rainfall and flooding in Mumbai led to prolonged telecom disruptions due to power cuts and submerged backup generators.
Why are undersea cables better than overland cables?
- Higher Capacity: Undersea cables can carry vast amounts of data, with total capacities reaching terabits per second, significantly surpassing the capabilities of satellite communications, which typically offer much lower bandwidth (around 1 gigabit per second).
- Lower Latency: The signal transmission time is considerably shorter with undersea cables than with satellite links. For example, latency over a fibre submarine cable is around 120 milliseconds, while satellite communications can introduce delays of approximately 650 milliseconds due to the long distances signals must travel to and from space.
- Cost-Effectiveness: Laying undersea cables is generally more economical than deploying satellite systems for large-scale data transmission. The initial investment in submarine cables, while significant, is offset by their capacity and reliability, making them a more sustainable option for long-term infrastructure.
- Reliability and Stability: Undersea cables are less susceptible to environmental factors that can disrupt overland cables, such as weather conditions or physical damage from construction activities. Their placement on the seabed provides a level of protection against many potential hazards.
- Global Connectivity: Submarine cables are essential for connecting continents and regions that are separated by water. They facilitate international data traffic and play a critical role in global communications, making them indispensable for the functioning of the Internet and other communication networks.
Does power failure create major problems?
- Disrupts Communication During Emergencies: Telecom towers and network operating centres require continuous power to function. When electricity is cut off, mobile networks and internet services fail, hindering disaster response.
- Example: During Cyclone Fani (2019), Odisha experienced massive power outages, causing mobile networks to shut down, and delaying rescue operations.
- Limits Functionality of Backup Systems: Most telecom towers rely on battery or diesel generators, but these backups last only a few hours. If the fuel supply is disrupted, networks remain down for extended periods.
- Example: In the Assam floods (2022), fuel shortages prevented telecom towers from running generators, prolonging communication blackouts.
- Affects Undersea & Land-based Network Infrastructure: Power failures at undersea cable landing stations and data centres can cause large-scale internet outages, affecting national and global connectivity.
- Example: A power failure at a Chennai cable landing station in 2021 disrupted international internet traffic.
Way forward:
- Strengthening Resilient Power Solutions: Deploy renewable energy sources like solar-powered telecom towers and battery storage systems to ensure uninterrupted network operations during disasters.
- Enhancing Risk-Informed Governance: Integrate disaster resilience planning into telecom policies, mandate robust backup power solutions, and establish coordinated emergency response frameworks for rapid service restoration.
Mains PYQ:
Q Critically examine the Supreme Court’s judgement on ‘National Judicial Appointments Commission Act, 2014’ with reference to the appointment of judges of higher judiciary in India.(UPSC IAS/2017)
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Note4Students
From UPSC perspective, the following things are important :
Mains level: Impact of climate change;
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.
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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)
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Note4Students
From UPSC perspective, the following things are important :
Prelims level: Periodic Labour Force Survey (PLFS)
Why in the News?
The latest edition of PLFS report (October-December 2024) has highlighted key labour market indicators.
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:
- Labour Force Participation Rate (LFPR): Percentage of people working or seeking jobs.
- Worker Population Ratio (WPR): Percentage of people employed.
- Unemployment Rate (UR): Percentage of job seekers unable to find employment.
- 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 |
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Note4Students
From UPSC perspective, the following things are important :
Prelims level: 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).
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:
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- Confirmed liquid oceans on Enceladus.
- Found methane lakes on Titan.
- Observed Saturn’s rings losing material into the planet’s atmosphere.
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PYQ:
[2009] Which one of the following planets has largest number of natural satellites or moons?
(a) Jupiter
(b) Mars
(c) Saturn
(d) Venus |
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Note4Students
From UPSC perspective, the following things are important :
Prelims level: Iron Age; Important Sites
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:
- 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).
- 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).
- 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?
- 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.
- Rigvedic Aryans knew gold, silver and copper whereas Indus Valley people knew only copper and iron.
- 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 |
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Note4Students
From UPSC perspective, the following things are important :
Prelims level: 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.
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.
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