UPSC Prelims Current Affairs for 4 February 2026

Pakhal Wildlife Sanctuary

February 4, 2026

Pakhal Wildlife Sanctuary Latest News

Recently, scientists from the Botanical Survey of India (BSI) have identified a new species of flowering plant in Pakhal Wildlife Sanctuary and named it as Dicliptera pakhalica.

About Pakhal Wildlife Sanctuary

Location: It is located in the Warangal district of Telangana.
Vegetation: It has mixed deciduous forests.
The Pakhal Wildlife Sanctuary houses the Pakhal Lake which was excavated on the orders of King Ganapati Deva of the Kakatiya empire in 1213 AD.
Flora: It consists of bamboo, teak, and diverse flora, including Terminalia, Pterocarpus, and Mohua.
It also consists of various kinds of herbs, shrubs and climbers.
Fauna: Leopard, wild boar, panthers, hyenas, sloth bear, chital, mountain gazelle, blackbuck etc.

Key Facts about Dicliptera pakhalica

It is a flowering plant species belongs to the Acanthaceae family
Habitat: The plant was found growing along stream banks and rocky areas.
It flowers between November and January, with fruiting extending from December to March.
The species occurs in association with other native plants such as Tarenna asiatica, Eranthemum purpurascens, Ruellia prostrata and Mallotus philippensis, among others.

Source: New India Express

Pakhal Wildlife Sanctuary FAQs

Q1: Where is Pakhal Wildlife Sanctuary located?

Ans: Telangana

Q2: What is Pakhal Wildlife Sanctuary known for?

Ans: Pakhal Lake and diverse flora/fauna

Myoglobin

February 4, 2026

Myoglobin Latest News

Researchers have developed a flexible, low-cost biosensor capable of detecting myoglobin which is associated with the early stages of a heart attack.

About Myoglobin

It is a small protein that accounts for about 2% of total muscle protein.
It is found predominantly in striated muscle tissue, namely skeletal muscle and cardiac muscle.
- Specifically, it is in the cytoplasm of cardiac myocytes and the sarcoplasm of oxidative skeletal muscle fibers.
It encodes a single polypeptide chain with one oxygen binding site.
It is one of the members of the globin superfamily, which also includes hemoglobin. It often gets compared structurally and functionally to hemoglobin.
- Hemoglobin has four polypeptide chains and four oxygen binding sites.
Composition: It’s made of amino acids, iron and other molecules that work together to hold onto oxygen.

Functions of Myoglobin

Transports Oxygen: It transports oxygen from the bloodstream to your muscles when they need it to convert stored energy into movements.
It serves as a sensitive indicator of cellular damage when detected in urine or plasma.
It serves as a buffer of intracellular oxygen concentrations and as an oxygen reservoir in muscle.
Enzymatic functions: It is necessary for the decomposition of bioactive nitric oxide to nitrate. The removal of nitric oxide enhances mitochondrial respiration.
Remove reactive oxygen species: It can do this by interacting with fatty acids.

Source: TH

Myoglobin FAQs

Q1: What is Myoglobin?

Ans: A protein that stores oxygen in muscles

Q2: Where is Myoglobin primarily found?

Ans: Skeletal muscle and cardiac muscle

Tender Years Doctrine

February 4, 2026

Tender Years Doctrine Latest News

The Delhi High Court recently held that the welfare and best interests of minor children must prevail over the application of the Tender Years Doctrine.

About Tender Years Doctrine

It is a prominent common law principle in family law and custody jurisprudence.
It presumes that children of "tender age" (generally under 5 years) should remain with their mother unless she is proven unfit.
The doctrine rests on several presumptions:
- Biological Bond: Infants have a natural attachment to mothers.
- Nurturing Instinct: Mothers are presumed better caregivers for young children.
- Developmental Needs: Early childhood requires maternal involvement.
- Emotional Security: Mother's presence provides psychological stability.
It has been in existence since the latter part of the 19th century.
The tender years doctrine is often raised in divorce proceedings.
However, its relevance has declined due to evolving views on gender equality and parenting roles.
Recent Delhi High Court Ruling:
- It held that the best interests and welfare of minor children are paramount and must override the application of the Tender Years Doctrine.
- The court also held that custody disputes must be resolved based on a comprehensive evaluation of the child’s overall well-being rather than stereotypical assumptions regarding parental roles.

Source: VERD

Tender Years Doctrine FAQs

Q1: What is the Tender Years Doctrine?

Ans: The Tender Years Doctrine is a common law principle in family law and child custody jurisprudence.

Q2: What does the Tender Years Doctrine presume?

Ans: It presumes that children of tender age, generally below five years, should remain in the custody of their mother unless she is proven unfit.

Q3: Since when has the Tender Years Doctrine been in existence?

Ans: It has been in existence since the latter part of the 19th century.

Q4: What did the recent Delhi High Court ruling state regarding the Tender Years Doctrine?

Ans: The Delhi High Court held that the best interests and welfare of the minor child must override the application of the Tender Years Doctrine.

Dholpur–Karauli Tiger Reserve

February 4, 2026

Dholpur–Karauli Tiger Reserve Latest News

The Rajasthan Forest and environment minister recently said in the Assembly that residents of villages in Dholpur–Karauli Tiger Reserve (DTR) will not be displaced without their consent.

About Dholpur–Karauli Tiger Reserve

It is located in the eastern part of Rajasthan, spanning across the Dholpur and Karauli districts.
It shares ecological continuity with the Ranthambhore Tiger Reserve to the west and lies close to the Chambal River on the east, which serves as a natural boundary and water source for the region.
It was officially declared in 2023, becoming Rajasthan’s fifth tiger reserve and India’s 54th tiger reserve.
It covers an approximate area of 1,111 sq.km.
The terrain is characterised by undulating plateaus, rugged hills, ravines, and dry deciduous forests, typical of the Aravalli and Vindhyan ranges.
Vegetation: The vegetation primarily consists of dry deciduous forests, interspersed with grassy patches, thorny shrubs, and riverine belts.
Flora: Some of the common tree species found here include:
- Dhok (Anogeissus pendula) – the dominant tree species across much of the reserve.
- Khair (Acacia catechu)
- Tendu (Diospyros melanoxylon)
- Babool (Acacia nilotica)
Fauna:
- The reserve hosts tiger, leopard, sloth bear, Indian wolf, striped hyena, herbivores such as spotted deer, sambar, nilgai, chinkara, and wild boar, and small mammals including Indian hare, porcupine and jungle cat.
- More than 250 species of birds have been documented here.

Source: TOI

Dholpur–Karauli Tiger Reserve FAQs

Q1: Where is the Dholpur–Karauli Tiger Reserve located?

Ans: It is located in the eastern part of Rajasthan.

Q2: Which river lies close to the eastern boundary of the Dholpur–Karauli Tiger Reserve?

Ans: The Chambal River lies close to its eastern boundary.

Q3: What is the dominant vegetation type found in the Dholpur–Karauli Tiger Reserve?

Ans: The dominant vegetation is dry deciduous forest, along with grassy patches, thorny shrubs, and riverine belts.

Solid Fuel Ducted Ramjet (SFDR) Technology

February 4, 2026

Solid Fuel Ducted Ramjet (SFDR) Technology Latest News

Recently, the Defence Research & Development Organisation (DRDO) has carried out a successful demonstration of Solid Fuel Ducted Ramjet (SFDR) technology from the Integrated Test Range (ITR), Chandipur off the coast of Odisha.

About Solid Fuel Ducted Ramjet (SFDR) Technology

It is an advanced air-breathing propulsion system using a solid fuel gas generator.
It has been developed by Defence Research and Development Laboratory (DRDL), Hyderabad in collaboration with other DRDO laboratories.
Working:
- It uses solid fuel instead of liquid fuel to make the system simpler, safer, and easier to store and transport.
- Unlike conventional rockets, SFDR does not carry an oxidiser, making it lighter and more efficient.
- SFDR provides sustained thrust over a longer duration and allows thrust modulation during flight.
- The SFDR system allows missiles to fly faster, farther and remain manoeuvrable throughout their flight, unlike conventional rocket-powered missiles.

Significance of Solid Fuel Ducted Ramjet (SFDR) Technology

SFDR technology significantly enhances long-range air-to-air missiles by providing sustained propulsion throughout much of the missile’s flight.
It places India into an elite league of nations possessing this technology that enables developing long-range air-to-air missiles to give tactical edge over the adversaries.

What is Ramjet?

It is a propulsion system that relies on the missile’s high forward speed to compress incoming air, eliminating the need for a compressor and enabling efficient high-speed flight.

Source: PIB

Solid Fuel Ducted Ramjet (SFDR) Technology FAQs

Q1: What type of missiles can SFDR Technology be used for?

Ans: Air-to-air missiles

Q2: What is SFDR Technology?

Ans: A solid fuel-based air-breathing propulsion system

Punatsangchhu-II Hydroelectric Project

February 4, 2026

Punatsangchhu-II Hydroelectric Project Latest News

India and Bhutan recently deliberated on the commercial optimization of power output from the Punatsangchhu-II Hydroelectric Project (1020 MW) and the early commissioning of the Punatsangchhu-I Hydroelectric Project (1200 MW).

About Punatsangchhu-II Hydroelectric Project

It is a 1020 MW run-of-the-river hydroelectric power project.
Location: It is located in the Wangdue Phodrang district of Bhutan on the right bank of the Punatsangchhu River.
The project is being developed by the Punatsangchhu II Hydroelectric Project Authority, under an Inter-Government Agreement (IGA) between the Royal Government of Bhutan and the Government of India.
It is funded by the Government of India (GoI): 30% grant and 70% loan at 10% annual interest, repayable in 30 equated semi-annual installments commencing one year after the mean date of operation.
With the completion of the Punatsangchhu-II project, Bhutan’s installed power generation capacity has increased by about 40 percent to over 3500 MW.
The project involves the construction of a 91 m-high and 223.8 m-long concrete gravity dam, along with a diversion tunnel with a discharge capacity of 1118 cubic metres per second.
The project also involves a 168.75 m-long and 22 m-high upper cofferdam and a 102.02 m-long and 13.5 m-tall downstream cofferdam.
It will comprise an underground powerhouse equipped with six Francis turbines of 170 MW capacity each.

Key Facts about Punatsangchhu-I Hydroelectric Project

It is a 1.2GW run-of-the-river hydroelectric power project.
Location: It is located in Wangdue Phodrang district of Bhutan on the left bank of Punatsangchhu River.
The project is being developed by Punatsangchhu I Hydroelectric Project Authority, an entity formed under a bilateral agreement signed by the Bhutanese government and the Government of India (GoI) in July 2007.
It is funded by the Government of India (GoI): 40% Grant and 60% Loan at 10% annual interest, repayable in 30 equated semi-annual installments commencing one year after the mean date of operation.
It is the largest hydro power project to be undertaken in Bhutan in partnership with the Government of India.
The project comprises a 130m-high and 239m-long concrete gravity dam.
It involves the construction of two diversion tunnels.
The facility includes an underground powerhouse that will generate power via six 200 MW turbines.

Source: TH

Punatsangchhu-II Hydroelectric Project FAQ's

Q1: Where is the Punatsangchhu-II Hydroelectric Project located?

Ans: It is located in the Wangdue Phodrang district of Bhutan on the right bank of the Punatsangchhu River.

Q2: What is the installed capacity of the Punatsangchhu-II Hydroelectric Project?

Ans: It has an installed capacity of 1020 MW.

Q3: What type of hydroelectric project is Punatsangchhu-II?

Ans: It is a run-of-the-river hydroelectric project.

Q4: How is the Punatsangchhu-II Hydroelectric Project funded?

Ans: It is funded by the Government of India with 30% as grant and 70% as loan.

Key Facts about Armenia

February 4, 2026

Armenia Latest News

The Chief of Defence Staff (CDS) is leading a high-level defence delegation on a four-day official visit to Armenia to strengthen bilateral defence engagement.

About Armenia

Location: It is a landlocked country, located in the south of Caucasus mountain range.
Bordering Countries: It is bounded by Georgia in the north, Azerbaijan in the east, Iran in the southeast and Turkey in the west.
Capital: Yerevan.

Geographical Features of Armenia

Terrain: The Lesser (or Little) Caucasus Mountains dominate much of Armenia’s landscape.
Much of Armenia’s soil—formed partly by residues of volcanic lava—is rich in nitrogen, potash, and phosphates.
Highest Peak: Mount Aragats (4,090 m) which is an extinct volcanic peak.
Climate: Highland continental, hot summers, cold winter climate.
Rivers: Aras, Hrazdan, Arpa, and Vorotan, rivers which provide hydropower and irrigation facilities to the country.
Lakes: Lake Sevan is the largest lake of Armenia.
Natural resources: Small deposits of gold, copper, molybdenum, zinc, bauxite

Source: New India Express

Armenia FAQs

Q1: What is the capital of Armenia?

Ans: Yerevan

Q2: Which mountain range runs along Armenia's northern border?

Ans: Caucasus

Exercise Khanjar-XIII

February 4, 2026

Exercise Khanjar-XIII Latest News

The 13th edition of the joint military Exercise KHANJAR between India and Kyrgyzstan begins recently at Misamari in Sonitpur district of Assam.

About Exercise Khanjar-XIII

It is the 13th edition of the annual India-Kyrgyzstan Joint Special Forces Exercise.
- Exercise Khanjar was first initiated in December 2011, in Nahan, India.
- Since then, the exercise has been held alternatively in India and the Kyrgyz Republic every year.
Khanjar-XIII Location: Misamari in the Sonitpur district of Assam.
The 14-day-long military exercise aims to enhance interoperability between the Special Forces of both nations.
The 2026 exercise will focus on joint operations in urban warfare and counter-terrorism scenarios under the United Nations mandate.
The training modules will include close-quarter battle techniques, room intervention procedures, hostage-rescue simulations, counter-terrorism operations, and joint tactical manoeuvres.

Source: NOA

Exercise Khanjar-XIII FAQs

Q1: What is Exercise Khanjar?

Ans: Exercise Khanjar-XIII is an annual joint special forces exercise between India and Kyrgyzstan.

Q2: When was Exercise Khanjar first initiated?

Ans: Exercise Khanjar was first initiated in December 2011.

Q3: Where was the first edition of Exercise Khanjar held?

Ans: The first edition was held in Nahan, India.

Q4: Where is Khanjar-XIII being conducted?

Ans: Khanjar-XIII is being conducted at Misamari in the Sonitpur district of Assam.