Current Affairs – June 15-16, 2025

{GS1 – A&C – Sites} Belum Caves

• Context (TOI): Belum Caves in Nandyal district, Andhra Pradesh, have been declared a Geo-Heritage Site by the Geological Survey of India (GSI).

About Belum Caves

• First discovered in 1884 by Robert Bruce Foote, later mapped in detail by H.D. Gebauer (1982–84).
• Formed in black limestone due to long-term underground water activity.
• Contain prominent stalactites and stalagmites, forming natural pillars and columns.

Robert Bruce Foote discovered India’s first Palaeolithic tool at Pallavaram and is known as the Father of Indian Prehistory.

Credit: Wikipedia

• Once inhabited by Buddhist and Jain monks; contains a Shiva Lingam and Patalaganga spring.
• Maintains a constant internal temperature of 33°C throughout the year.
• Underground water is believed to be connected to a village well and influenced by the Penna River.
• Excavations revealed 4,500-year-old artifacts, indicating pre-Buddhist habitation.
• Unique Structures: Includes named sections like Meditation Hall, Thousand Hoods, Airavatham, and Mayamandiram.

• Belum is the second-longest natural underground cave system in India.

Mammoth Cave (USA) is the world’s longest natural underground cave system. Krem Liat Prah (Meghalaya) is India’s longest natural underground cave. Stalactites hang from cave ceilings, created by mineral-rich water dripping over long periods. Resemble tapered icicles, forming complex roof structures in limestone caves.  Stalagmites Rise from the floor below stalactites, created by drip water mineral deposits. Can join with stalactites to form pillars or columns, altering the cave’s internal structure.

About Geo-Heritage Sites

• Sites with rare and scientifically important geological, geomorphological, or paleontological features.
• Components: Include caves, rock sculptures, fossils, minerals, meteorites, and stratified sediments.
• Nodal Agency: Declared and maintained by the Geological Survey of India (GSI).
• Purpose: Aimed at conservation, research, education, and geotourism promotion.
• Other Examples: Includes Lonar Crater (Maharashtra), St. Mary’s Island (Karnataka), and Erra Matti Dibbalu (Andhra Pradesh).

About Geological Survey of India (GSI)

• Set up in 1851 with the appointment of Thomas Oldham; earlier initiated by John McClelland in 1846 under the East India Company.
• One of the oldest scientific bodies in India; second only to the Survey of India (1767).
• Nodal Ministry: Functions as an attached office of Ministry of Mines.
• Headquarters: Kolkata, with six regional offices and state-level units.
• Mandate: Responsible for geoscientific surveys, mineral exploration, natural hazard studies, and geo-heritage declarations.

{GS2 – IR – Issues} Regulatory Framework of Global Shipping

• Context (TH): Recent incidents like MV Wan Hai 503 catching fire and MSC ELSA 3 sinking off Kerala raised concerns over maritime safety and environmental risks.

Global Shipping Governance Framework

• IMO Oversight: IMO sets global norms for safety, security, and pollution control in maritime transport.
• Flag State Responsibility: The country whose flag the ship flies ensures compliance with IMO rules through certification and inspections.
• Flags of Convenience (FOC): It refers to the practice of registering ships in foreign countries to benefit from lax regulations, e.g. Liberia, Marshall Islands, which raises concerns about oversight.
  • Over 30% of merchant vessels are registered under FOC regimes.
• Port State Enforcement: Countries inspect foreign ships entering their ports to enforce IMO standards under regional frameworks.

China and Greece together own around 25% of the global merchant fleet. India operates around 1,500 merchant vessels and handled 1.4 billion tonnes of cargo in 2023–24.

In India

• The Directorate General of Shipping is India’s maritime authority under the Ministry of Ports, Shipping and Waterways. It is responsible for implementing IMO conventions in India.

Liability for Cargo Loss and Environmental Damage

• Cargo Loss Claims: Ship owners compensate Bill of Lading holders for lost cargo.
• Unlimited Environmental Liability: Ship owners are fully liable without any cap for pollution damage under international conventions.
• Insurance Support: Protection and Indemnity (P&I) Clubs cover liabilities like oil spills, cargo loss, and third-party injury.

Bill of Lading It is a contract between the shipper and ship owner specifying cargo details and delivery terms. Acts as a title document, passing ownership to the consignee after payment. The bill holder has legal rights to claim for cargo loss or damage. Protection and Indemnity (P&I) Clubs P&I Clubs are associations that insure ship owners against third-party liabilities. Members pool resources to cover high-cost claims like oil spill cleanup or legal penalties. They help reduce the financial burden on ship owners in major maritime accidents.

Salvage Responsibilities Under the Nairobi Convention

• Owner Obligation: The ship owner must remove wrecks located within 200 nautical miles of coastline.
• Cost Burden: All salvage and environmental restoration costs fall on the ship owner.
• Government Action: If the owner fails, coastal states can act and later recover costs from the owner.
• Application in India: India enforces this under DG Shipping rules, as seen in the MSC ELSA 3 case.

Nautical Mile: A nautical mile equals 1,852 metres and corresponds to one minute of latitude on Earth’s surface. Nairobi International Convention on the Removal of Wrecks, 2007 The convention aims to ensure the prompt and effective removal of shipwrecks that threaten navigation or the marine environment. Jurisdictional Scope: It applies to wrecks beyond territorial seas, with an option for states to extend it within territorial waters. Administration: The convention is administered by the IMO and provides a uniform legal framework for wreck removal. Territorial Sea: A coastal state’s maritime zone extending up to 12 nautical miles from its baseline with full sovereignty.

IMO Conventions and India’s Status

Name	Purpose	India Signed?	Note
SOLAS (1974)	Sets safety standards for ships	Yes	Introduced post-Titanic, mandates lifeboat capacity
MARPOL (1973)	Prevents pollution via 6 annexes	Yes	India enforces 0.5% sulfur limit under Annex VI
Bunkers Convention (2001)	Covers oil pollution from fuel	Yes	Strengthens liability for bunker-related spills
Nairobi Wreck Convention (2007)	Mandates for wreck removal	Yes	Applies up to 200 nautical miles from the coast
Ballast Water Convention (2004)	Prevents invasive species via ballast	No	High retrofitting costs delay India’s adoption
HNS Convention (2010)	Covers Hazardous and Noxious Substances (HNS) cargo liability	No	Complex legal changes delay ratification

International Maritime Organisation (IMO)

• UN specialised agency established in 1948 regulating international shipping for safety, security, & environmental protection.
• Headquarters: London.
• Members: 176 members. India joined the IMO in 1959 and is regularly elected to its Council, shaping global maritime norms.
• It frames binding rules on ship design, operation, crew standards, and pollution control.
• Institutional Structure: It functions through the Assembly, Council, and key committees like the Maritime Safety Committee (MSC) and Marine Environment Protection Committee (MEPC).

{GS3 – Envi – CC} Temperature Standardization for Air Conditioners (ACs)

• Context (TH I HT I IE): The guidelines proposed to limit the operational temperature range of air conditioners across the country.
• The new proposed guidelines requires new air-conditioners hardwired to operate in a fixed temperature range of 20 to 28 degrees Celsius.
• It is based on guidelines issued by Bureau of Energy Efficiency (BEE) in 2018 for major commercial establishments to conserve energy through optimum temperature settings for air conditioners.
• In 2020, the government mandated that all air conditioners have a default setting of 24˚C. However, this still allowed individuals to control the temperature settings to their choice.

Need of Temperature Standardization for ACs

• Reduce Electricity Consumption: India’s cooling demand amounted to around 50 GW, or roughly 1/5^th of India’s peak power demand. By increasing the temperature by 1˚C, India can save 6% of electricity.
  • BEE estimates that the total connected load in India due to AC will be about 200 gigawatt (GW) by 2030 and could further increase as only about 6% of households use one or more ACs currently.
• Power Efficiency: Having a fixed range would likely increase power-consumption efficiency in closed public places, such as conference rooms and auditoriums.
• Save Money: Tighter energy rules for ACs could save up to 60 gigawatts of peak demand by 2035, which would prevent the need to spend RS 7.5 trillion on building new power plants and grid systems.
• Ease Pressure on the Grid: In summer, many homes and buildings set their ACs as low as 16°C, straining the power grid and causing frequent outages.
• Global Practices: Countries, like Japan, already have regulations in place for the functioning of air conditioners. It encourages a default setting for ACs at 28 degrees Celsius in public buildings.

Concerns

• Limited Impact: The change may directly affect only a small subset of users who prefer to keep their living spaces below 20°C. Thus, its total impact on energy use and emissions will likely be limited.
• Limitation of Choice: Individuals may feel their freedom to choose preferred indoor temperatures is being restricted, especially in private spaces or homes.
• State Overreach Perception: Mandating temperature settings can be seen as government overreach into personal or business decisions.
• Comfort vs Regulation: Thermal comfort varies from person to person. Standardization may lead to discomfort for some, impacting productivity and well-being.

Alternative Measures

• Better Building Design: It can significantly reduce or even eliminate the need for air-conditioning. While energy-efficient building codes already exist, their implementation has been limited and inconsistent.
• Improve Efficiency of ACs: The BEE mandates a star-rating system, with 1-star models being the least efficient and 5-star models the most efficient. However, only about 20% of ACs purchased in the market today are 5-star variants.
• Other: Greater public awareness, mandatory public procurement of 5-star ACs, lower GST rates for high-efficiency models, and exchange programmes for older ACs etc.

{GS3 – Envi – CC} Why are Global oceans darkening?

• Context (IE): A study shows 21% of global oceans have darkened in 20 years.

What is Ocean Darkening?

• Ocean darkening refers to the shrinking of the photic zone.
• 21% of global oceans have darkened between 2003–2022. Most prominent darkening was observed in open oceans, particularly in climate-sensitive zones like the Arctic, Antarctic and the Gulf Stream region.

Photic zone is the sunlit upper layer of the ocean, extending up to 200 meters, to support photosynthesis. It acts as the base for nearly 90% of the world’s marine life.

Credit: News18

Causes

• Agricultural Runoff: Excess fertilisers, sewage & organic waste enter oceans via rivers, triggering algal blooms blocking sunlight from penetrating the water.
• Increased Sedimentation: Driven by soil erosion, deforestation, land-use changes & intensifying monsoons, increases the flow of sediments into the ocean.
• Plankton Dynamics: Climate change alters phytoplankton composition, impacting how sunlight is absorbed or reflected.
• Rising Sea Surface Temperature: Warmer waters change biological productivity and circulation patterns disrupting light penetration.
• Ocean Currents: Altered ocean currents redistribute nutrients & sediments unevenly.

Impacts

• Marine Behaviours: Affects species feeding, migration and reproduction cycles, disturbing the balance of marine ecosystems.
• Loss of Species: Disruption of light-sensitive organisms like Calanus copepods signals broader threats to marine food chains.
• Carbon Sequestration: Ocean darkening reduces phytoplankton productivity, limiting CO₂ absorption & weakening the ocean’s climate-buffering role.
• Livelihoods at Risk: Shrinking fish stocks and species migration threaten coastal economies, food security and public health.

{GS3 – S&T – BioTech} Deoxyribonucleic Acid (DNA) Analysis

• Context (IE): After the Air India Boeing 787 Dreamliner crash in Ahmedabad, authorities are using DNA analysis to identify the remains of those killed in the accident.

What is DNA Analysis?

• Also known as DNA profiling, it is a process used to identify and analyze genetic material from biological samples, like blood, saliva, or tissue.
• Process: It involves extracting, amplifying, and comparing DNA sequences to create unique individual profiles.
• Reference Samples: Collected from biological relatives to identify to whom the collected DNA belongs. Parents and children of the victim are ideal candidates for providing these samples, as they share 50% of each other’s DNA.
  • Except identical twins, every person has a unique DNA that is present in nearly every cell of their body.
• Identification of Individuals: DNA identification is the gold standard for identifying human remains, especially after mass fatality events in which bodies might not be easy to identify otherwise.
• Other Applications: This technique has various applications, including forensic investigations, paternity testing, and medical research.

Methods of DNA Analysis

Short Tandem Repeat (STR) Analysis

• STR analysis is a DNA profiling method that examines specific regions in the DNA where short sequences of bases (2–6 base pairs) are repeated in tandem.
• After analysing 15 or more of these hyper-variable regions of DNA, the resulting profile can be used to ascertain family relationships.
• Can be performed on very small/degraded DNA samples, making it suitable for forensic investigations.
• The number of repeats at STR regions varies significantly between individuals, making it ideal for personal identification.

Mitochondrial DNA (mtDNA) Analysis

• mtDNA analysis is used when nuclear DNA is degraded or unavailable, especially in old or poorly preserved human remains.
• Unlike nuclear DNA, mtDNA is found in the mitochondria and exists in multiple copies per cell.
• Since mtDNA is inherited maternally and remains largely unchanged, it can be used to identify individuals by matching samples with maternal relatives.

Y Chromosome Analysis

• In this method, a panel of STR on Y chromosomes is examined to match the remains of the victim with their male relatives.
• This can be useful when close relatives are not available for comparison: any member of the paternal line may be used for matching.

Humans have two types of sex chromosomes, X and Y: biological males typically have one X and one Y chromosome, and biological females typically have two X chromosomes.

Single Nucleotide Polymorphisms (SNPs) Analysis

• A SNP is a variation in the DNA sequence where a single base – A, C, G, or T, at a specific location differs among people.
• Each SNP represents a difference in a single DNA building block, called a nucleotide. SNPs occur normally throughout a person’s DNA. They occur almost once in every 1,000 nucleotides on average, which means there are roughly 4 to 5 million SNPs in a person’s genome.
• Since SNPs are unique to individuals, they can be used for identification by comparing DNA from personal items like a toothbrush or hairbrush with reference samples.
• The method is typically used when the DNA to be analysed is highly degraded. However it is not as effective as STR analysis.

{Prelims – PIN World – Middle East} Suez Canal

• Context (IE): A recent conflict between Iran and Israel has reignited fears of surging oil prices and more trade disruptions. One of the major concerns is the potential impact on the Suez Canal.

About Suez Canal

• The Suez Canal is a 193-km-long artificial waterway connecting the Red Sea to the Mediterranean Sea through the Isthmus of Suez. It was constructed over a decade and opened on November 17, 1869.
• The canal is one of the world’s busiest and most strategic maritime routes, linking the Mediterranean Sea to the Indian Ocean. The other important shipping route is the Panama Canal.

Importance of Suez Canal

• Strategic Trade Route: Connects the Mediterranean Sea to the Red Sea, serving as a vital link between Europe and Asia.
• Saves Time and Cost: Reduces travel distance between Europe and Asia by up to 7,000 km. Before its construction, ships had to navigate around the Cape of Good Hope in South Africa.
• Handles Major Global Trade: The Suez Canal accounts for nearly 12-15% of global trade, according to IMF data. It is also a key passage for 8-9% of global energy flows.
• For India: Like many countries, India relies heavily on the Red Sea route, with nearly 80% of its exports to Europe passing through the Suez Canal.

Issues related to the Suez Canal

• Congestion: The 205 m-wide, 24 m-deep Suez Canal is the world’s largest shipping chokepoint. Despite expansions, it remains congested with frequent delays. E.g. In March 2021, cargo ship ‘Ever Given’ blocked the canal for over a week, disrupting global trade.
• Geopolitical Conflicts: The Suez Canal was also the focal point of both the 1967 and 1973 Arab-Israeli wars and was shut from 1967 to 1975.
• Increased Trade Cost: Rerouting of trade around Africa due to Red Sea crisis increases freight costs.
• Security Threats: Rising piracy, drone attacks, & regional conflicts increase risks for commercial shipping.

Strait of Hormuz

• Located at the mouth of the Persian Gulf. It lies between Oman and Iran. It links the Gulf north of it with the Gulf of Oman to the south and the Arabian Sea beyond.
• It is 21 miles (33 km) wide at its narrowest point, with the shipping lane just two miles (three km) wide in either direction.
• Importance: About a fifth of all oil traded at sea passes through it. It is also the route used for nearly all the Liquefied Natural Gas (LNG) produced by the world’s biggest LNG exporter, Qatar.

Panama Canal

• Completed in 1914, the Panama Canal connects the Atlantic and Pacific Oceans through the narrow Isthmus of Panama.
• For ships traveling between the east and west coasts of the United States, the canal reduces the journey by 8,000 nautical miles, avoiding the dangerous passage around Cape Horn.

{Prelims – Sci – Bio} Muscle Stem Cell Rejuvenation

• Context (TH): Prostaglandin E2 (PGE2) can restore the muscle repair ability of aged stem cells in mice.

• Prostaglandin E2 (PGE2) is a compound involved in inflammation and used clinically to induce labour. It is naturally produced in the body, particularly after injury.

Key Findings

• Daily injections of PGE2 helped aged mice regain muscle strength and mass.
• Older mice regained the ability to regenerate damaged muscle.
• Muscle fibres grew larger, muscle mass increased, and strength improved by about 20%.

Muscle Stem Cells (MuSCs)

• These are adult stem cells residing in skeletal muscle.
• MuSCs repair muscles by dividing and rebuilding tissue after damage. In young muscles, MuSCs work fast, but in older muscles, they stay inactive.

Stem cells: The cells which can make more cells like themselves and self renew.

How does it work?

• PGE2 is normally produced by the body after injury and tells MuSCs to activate. This signal fades with age, but injections restored it.
• PGE2 reopened parts of the genome that had “shut down” with age.
• It also reduced AP-1, an aging-related stress signal in the cells, which becomes overactive in aging MuSCs.
• Effect: Stem cells acted like young cells—dividing, repairing, and responding to damage.

Rationale and Significance

• Faster Recovery: PGE2 could help older adults heal quicker from injuries or surgeries.
• Targeted Approach: Acts directly on MuSCs, offering precise treatment.
• Sarcopenia Treatment: Could help millions suffering from muscle loss, frailty, and slow recovery.

Sarcopenia is a type of muscle loss that occurs with ageing and/or immobility.

{Species – Reptiles – LC} Indian Rat Snake (Ptyas mucosa)

• Context (TH): Kerala is considering a proposal for notifying Indian Rat Snake, regionally known as Chera as the official reptile.

Credit: TH I IUCN

• Also known as the Oriental rat snake, it is a non-venomous snake.
• Distribution: Afghanistan; Bangladesh; Cambodia; China; India; Indonesia; Pakistan; Vietnam etc.
• Habitat: The snake is found in diverse habitats, including forests, forest clearings and edges, open tropical dry forests, savannas, scrublands, plantations etc.
• Physical description: Typically grows to be 1.5-2 m long. Color ranges from pale browns to nearly black.
• Diet: Carnivorous. It feeds on rodents, but also eats birds, lizards, frogs and other snakes.
• Conservation Status: IUCN: Least Concern (LC) I WPA: Schedule I
• Threats: Over-exploitation for food, skins, and medicinal purposes, as it is heavily traded.
• Significance: Plays a major role in controlling the rodent population, thus known as friends of farmers.