UPSC Essentials brings to you its initiative of subject-wise quizzes. These quizzes are designed to help you revise some of the most important topics from the static part of the syllabus. Attempt today’s subject quiz on Environment and Geography to check your progress. Click Here to read the UPSC Essentials magazine for August 2026. Share your views and suggestions in the comment box or at manas.srivastava@indianexpress.com2. All three species of orangutans are classified as Vulnerable on the IUCN Red List.3. They are native to South America.How many of the statements given above are correct?(a) Only one(b) Only two(c) All three(d) NoneRelevance: The question tests knowledge of orangutan species, their conservation status and ecological characteristics, linking biodiversity with species-level conservation.Explanation— Local residents roaming about a forest area near a village in Odisha’s Balasore district had an unusual sighting on Tuesday — five tiny orangutans. Residents near Badapai village in Balasore’s Bhograi area spotted five juvenile orangutans. Officials suspect the apes were brought into the state as part of an international wildlife-smuggling operation.— Orangutans are Asia’s only great apes and hold the title of the largest tree-dwelling (arboreal) mammals on earth. Native only to the rainforests of Borneo and Sumatra, these highly intelligent primates are currently facing a severe survival crisis, with all three species classified as Critically Endangered on the IUCN Red List. Hence, statement 1 is correct and statements 2 and 3 are not correct.Therefore, option (a) is the correct answer.Story continues below this adQUESTION 2With reference to the bats, which of the following statements are correct?1. They carry two distinct copies of the genes involved in producing antibodies.2. They are completely immune to viruses.3. They help in plant pollination and in the control of the insect population.Select the correct answer using the codes given below:(a) 1 and 2 only(b) 2 and 3 only(c) 1 and 3 only(d) 1, 2 and 3Relevance: The question tests understanding of the ecological roles of bats, including pollination, seed dispersal and natural insect control. The topic connects species-specific biological adaptations with ecosystem services, biodiversity conservation and the ecological importance of lesser-known wildlife.ExplanationStory continues below this ad— The scientific world has long been intrigued by how bats can carry viruses that can cause severe disease while rarely becoming seriously ill themselves. As per a report published by Science Daily, researchers at Tulane University, working with collaborators at Stanford University and the Centers for Disease Control and Prevention, may now have identified part of the answer.— A study published in Science Advances found that the world’s largest family of bats carries two distinct copies of the genes involved in producing antibodies, which help the immune system identify and fight infections. On the other hand, every other known mammal has only one such set of genes. Hence, statement 1 is correct.— Bats are not completely immune to viruses. Instead, many species have evolved a remarkable ability to tolerate certain viral infections without developing severe disease. Their immune system can detect and control viruses effectively while keeping inflammation in check. This is important because, in humans, an overactive immune response can cause significant tissue and organ damage during some infections. Hence, statement 2 is not correct. (Image Source: Unsplash)— Bats appear to have adaptations linked to the high metabolic demands of flight, which may help them manage cellular stress and inflammation more efficiently. Their long evolutionary coexistence with certain viruses may have further shaped this relationship, allowing the host and virus to coexist with limited illness.Story continues below this ad— Bats can carry several viruses without getting seriously ill. These viruses can be different in humans and other animals. When a virus spills over from bats to a new species the new host might not have the same biological protections that help bats control infection.— Bats are important for plant pollination and for the control of the insect population. By studying how their immune systems keep viruses in check, this will help find better ways to prevent and treat disease. Hence, statement 3 is correct.Therefore, option (c) is the correct answer.QUESTION 3With reference to the different flood situations, consider the following pairs:1. Normal Flood – If the water level of the river crosses its Warning level.Story continues below this ad2. Severe Flood – If the water level of the river crosses the Highest Flood Level recorded.3. Above Normal Flood – If the water level of the river is between Danger Level and the Highest Flood Level.How many of the pairs given above are correctly matched?(a) Only one(b) Only two(c) All three(d) NoneRelevance: The question tests understanding of flood classification, river-water levels and flood-warning thresholds, which are important components of physical geography and disaster management. It also connects river hydrology with flood-risk assessment, early-warning systems and disaster resilience, making it relevant for UPSC Prelims 2027.ExplanationStory continues below this ad— The Central Water Commission has categorised various flood situations, for monitoring the floods in the country though its flood forecasting network, into four different categories namely Normal, Above Normal, Severe and Extreme depending upon the river water level with reference to warning level, danger level, and highest flood level.— The river is said to be in “NORMAL FLOOD” situation at any flood forecasting sites when the water level of the river is below the warning level. Hence, pair 1 is not correct.— If the water level of the river at flood forecasting site touches or crosses its Warning level, but remains below the Danger Level of the site then the flood situation is called the “ABOVE NORMAL” situation. Hence, pair 3 is not correct.— If the water level of the river at the forecasting site touches or crosses Danger Level but below the Highest Flood Level of the forecasting then the flood situation is called “SEVERE FLOOD” situation. Hence, pair 2 is not correct.Story continues below this ad— The flood situation is said to be “EXTREME” when the water level of the river touches or crosses the “HIGHEST FLOOD LEVEL” recorded at any forecasting site so far.Therefore, option (d) is the correct answer.(Source: http://www.cwc.gov.in)QUESTION 4With reference to the conservation of critically endangered birds in India, which one of the following species has recorded the country’s first birth through the “jumpstart” method?(a) Great Indian Bustard(b) Bengal Florican(c) Lesser Florican(d) Great HornbillRelevance: The question tests knowledge for conservation efforts of a critically endangered bird and an important species in India’s biodiversity conservation framework. It links a recent conservation breakthrough with species recovery, captive breeding, habitat conservation and human-assisted reproduction, making it relevant for UPSC Prelims 2027.Explanation— For the first time in a decade, Gujarat saw the birth of a Great Indian Bustard (GIB) chick on March 26 — after a “trans-state conservation effort” that involved an “arduous 770-km road journey” across a “halt-free corridor” to transport a 15-day old fertile egg from Sam in Rajasthan’s Jaisalmer district to Naliya in Gujarat’s Kutch district.Story continues below this ad— This is the country’s first birth of the critically endangered bird under the “jumpstart” method, where a female GIB in Kutch, which had laid an infertile egg, incubated a fertile egg chosen from a captive breeding centre in Jaisalmer.— This is a significant development for the GIB conservation programme. Gujarat has only three surviving GIBs in the wild, and all are female. Hence, their eggs are all infertile.— There are only an estimated 150 GIBs in the wild in the country, mostly in Rajasthan. The large bird, a key indicator species of the grassland habitat, has faced population decline over the years due to hunting, habitat loss, and, in recent years, collisions with energy transmission lines that criss-cross their habitat in Rajasthan and Gujarat.Therefore, option (a) is the correct answer.QUESTION 5With reference to El Niño, consider the following statements:1. It is warming in the sea surface temperatures recorded along the equatorial Pacific Ocean.2. In India, it is linked with high temperatures and subdued rainfall.3. It can also lead to a decline in marine productivity across the equatorial Pacific Ocean.How many of the statements given above are correct?(a) Only one(b) Only two(c) All three(d) NoneRelevance: The question tests understanding of the El Niño–Southern Oscillation (ENSO) and its ocean–atmosphere interactions in the tropical Pacific. It is relevant for analysing the relationship between Pacific Ocean warming, monsoon variability, rainfall deficiency and temperature anomalies in India.Explanation— Even before the ongoing El Niño becomes a full-blown event, Isro’s Oceansat-3 observations have captured a decline in marine productivity across the equatorial Pacific Ocean in recent months and linked it to the warming oceans. Hence, statement 3 is correct.— El Niño is the abnormal warming in the sea surface temperatures recorded along the equatorial Pacific Ocean. This surplus warming alters the atmospheric wind and ocean wave flow patterns and carries the potential to alter global weather. El Niño is linked with extreme weather, heatwaves, high temperatures, and subdued rainfall. Hence, statements 1 and 2 are correct.— Launched in 2022, Isro’s Oceansat-3 (also known as Earth Observation System EOS-06) is designed for global monitoring of the atmosphere along with observing the biological and physical parameters of the ocean. It has multi-sensor data gathering ability coming from the Ocean Colour Monitor-3 (OCM-3) and Scatterometer sensors.Therefore, option (c) is the correct answer.Previous Daily Subject-Wise-QuizDaily Subject-wise quiz — History, Culture, and Social Issues (Week 163)Daily subject-wise quiz — Polity and Governance (Week 179)Daily subject-wise quiz — Science and Technology (Week 179)Daily subject-wise quiz — Economy (Week 179)Daily subject-wise quiz — Environment and Geography (Week 178)Daily subject-wise quiz – International Relations (Week 178)Subscribe to our UPSC newsletter and stay updated with the news cues from the past week.Stay updated with the latest UPSC articles by joining our Telegram channel – IndianExpress UPSC Hub, and follow us on Instagram and X