UPSC Prelims
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Prelims Pinpointer
Prelims Pinpointer — September 6, 2026
Today’s high-yield Prelims facts — China’s Yarlung Zangbo mega dam, CBI’s general consent framework in Bihar, striped hyena conservation, a low-cost RNA-virus blood test, and dragonflies as ecological bioindicators
🏞️ Yarlung Zangbo Dam
⚖️ CBI General Consent
🐾 Striped Hyena
🩸 Zika & Hepatitis C Test
🪰 Dragonfly Bioindicators
🏞️
China’s Mega Dam on the Yarlung Zangbo (Brahmaputra)
News Context
- A glacial collapse and flash flood on the Nepal-China border on August 26 raised fresh safety concerns, but China is going ahead with its mega dam on the Yarlung Zangbo (Brahmaputra) in Tibet, close to India’s border — included in China’s 15th Five-Year Plan for renewable energy.
Key Facts for Prelims
- The river is called Yarlung Zangbo in Tibet/China, becomes the Brahmaputra in India (entering via Arunachal Pradesh, called the Siang, then the Dihang).
- Built on the lower reaches near the “Great Bend,” in a seismically active zone — called the “project of the century” / Yarlung Zangbo Lower Reaches Hydropower Project, with five power stations.
- Expected capacity: ~60 GW, 300 billion kWh/year output — over 3x larger than the Three Gorges Dam.
- Described as “run-of-the-river” but will still include a reservoir near Mainling, upstream of Nyingchi; water diverted via a ~40-km tunnel through five 12-GW powerhouses.
- China’s earlier dam at Zangmu (operational 2010) supplies ~26% of Tibet’s electricity demand.
Why This Matters for India
- Downstream impact on water flow into Arunachal Pradesh and Assam; seismic risk in an earthquake-prone zone; irregular hydrological data-sharing under the Expert-Level Mechanism; and a strategic angle since China holds the upper riparian position.
Exam trap: The river is called Dihang in a stretch within Arunachal Pradesh (downstream of Siang) — NOT in Tibet. In Tibet it is always Yarlung Zangbo.
Source: The Hindu
⚖️
CBI’s Powers in Bihar: General Consent Under the DSPE Act, 1946
News Context
- On September 3, the Bihar Home Department issued a notification restructuring CBI’s powers in the state — the CBI can freely investigate Central employees/PSUs/private persons, but needs prior consent for Bihar government employees.
What Is the CBI?
- India’s premier investigating agency — has no separate parliamentary Act of its own; functions under the Delhi Special Police Establishment (DSPE) Act, 1946.
General Consent Under Section 6, DSPE Act — Key Facts
- The notification, issued under Section 6 of the DSPE Act, 1946, supersedes all previous Bihar notifications and creates a two-tier consent system: automatic consent for Central employees/PSUs/private persons, and case-by-case consent for Bihar government employees/state institutions.
- General consent: blanket, standing permission for specified case categories. Specific consent: approval needed separately for each case. Several states (West Bengal, Kerala, Punjab) have withdrawn general consent entirely — Bihar’s move restructures rather than withdraws it.
- Important clarification: consent requirements apply only to CBI’s own executive action — a High Court or Supreme Court can order a CBI probe in any state regardless of consent, since courts derive power directly from the Constitution.
| Provision | Relevance to CBI |
|---|---|
| Entry 2, State List | “Police” is a state subject — root cause of the consent requirement |
| Entry 8, Union List | Basis for CBI’s existence as “Central Bureau of Intelligence and Investigation” |
| Entry 80, Union List | Parliament can extend police powers to another state only with consent |
| Articles 32 & 226 | Allow courts to order CBI probes without needing state consent |
| Article 21 | Right to a fair investigation (basis of Vineet Narain judgment) |
Exam trap: This episode illustrates cooperative/competitive federalism — states can regulate the CBI’s entry and jurisdiction despite it being a Central agency, an important nuance of India’s quasi-federal structure.
Source: The Hindu
🐾
Striped Hyena Conservation in India
News Context
- The Indian striped hyena, despite the highest legal protection under Indian wildlife law, remains under-conserved — cultural superstitions, lack of population data, and no unified national conservation plan put this scavenger at risk.
Key Facts for Prelims
- A scavenger species, feeding on carrion rather than hunting live prey; global population estimated at 5,000–14,000, Indian population at 1,000–3,000 — India may hold one of the largest single-country populations.
- India has no official dedicated census — figures are estimates. Listed under Schedule I of the Wildlife (Protection) Act, 1972 — the highest legal protection.
- No dedicated National Action Plan; conservation is largely state-specific (e.g. West Bengal awareness campaigns, Tamil Nadu’s ₹14 lakh allocation for lesser-known endangered species).
Pre-2022 Schedules
The Wildlife (Protection) Act, 1972 originally had 6 Schedules (I–VI); Schedule I gave the highest protection.
Post-2022 Amendment
Number of schedules reduced from 6 to 4; older books may still show the six-schedule system.
Source: The Hindu
🩸
New Low-Cost Method to Detect Zika and Hepatitis C in Whole Blood
News Context
- Researchers developed a low-cost method to detect Zika virus and Hepatitis C virus directly in whole blood, using a blood-drying protocol plus a heater and low-cost sensor — results in about 2 hours, accuracy comparable to top-tier labs.
Key Facts for Prelims
- Both are RNA viruses — blood naturally contains enzymes that rapidly destroy RNA, making direct whole-blood testing difficult; traditional methods needed expensive RNA-purification equipment.
- The new blood-drying technique protects viral RNA from destruction, needing only a heater and simple sensor — a major cost and speed advantage in resource-limited settings.
Important Concepts
- RNA viruses include Zika, Hepatitis C, Influenza, HIV and coronaviruses (SARS-CoV-2); RNA is less stable than DNA, making detection harder.
- Zika is spread by the Aedes mosquito (same as dengue/chikungunya) and can cause microcephaly in babies of infected mothers.
- Hepatitis C spreads via infected blood and can cause chronic liver disease, cirrhosis and liver cancer — India has committed to WHO’s Hepatitis C elimination target, supported by the National Viral Hepatitis Control Programme.
Source: The Hindu
🪰
Dragonflies as Bioindicators
News Context
- Dragonflies and damselflies (order Odonata) act as bellwethers of ecosystem health, even as surveys report declining populations across India, raising concerns about pesticide overuse and climate-linked habitat change.
Key Facts for Prelims
- India is home to around 600 species of Odonata; new species are frequently discovered in the North-East and the Nilgiri–Western Ghats region. Called “sitara” in Hindi. Ancestors dating back ~300 million years had a wingspan of up to 72 cm.
- Two-world life cycle: aquatic nymph stage, terrestrial/aerial adult stage — this dual dependence makes them reliable bioindicators.
- Natural pest controllers: a growing nymph can consume ~100 mosquito larvae a day; adults hunt leafhoppers, aiding pest management in paddy fields.
- Threats: pesticides like fipronil, and climate change (rainfall/drought shifts), especially for endemic Western Ghats species like the Blue hawklet (Hylaeothemis apicalis).
- Near-360° vision via large compound eyes, with 16+ visual opsin genes (vs 4 in humans) — allows UV-light detection.
Bioindicator concept: an organism whose presence, absence or health reflects environmental quality — dragonflies’ dual aquatic-terrestrial dependence makes them ideal indicators of overall ecosystem health.
Source: The Hindu

