Biogeography & Ecosystems

Statement 1 is Incorrect: Mangroves do not store freshwater, nor are they naturally suited for paddy cultivation. In fact, the clearing of mangrove forests to create agricultural land (like paddy fields) has historically been a primary driver of their destruction, rather than a reason for their protection. Statement 2 is Incorrect: Mangroves are halophytes, meaning they are highly salt-tolerant, not salt-sensitive. While their specialized root systems have ultrafiltration mechanisms to exclude salt, they do not convert coastal lands into freshwater zones. Furthermore, clearing mangroves for shrimp and aquaculture farms is a major threat to these ecosystems, not a conservation rationale. Statement 3 is Correct: In the context of climate resilience, mangroves act as natural bio-shields. Their dense root networks (such as stilt roots and pneumatophores) stabilize coastal soils and dissipate tidal energy, protecting coasts from storm surges and cyclones. Additionally, they are highly productive ecosystems that provide sustainable biomass resources (like timber, honey, and fish breeding grounds), forming a crucial livelihood base for rural coastal communities. Therefore, option D is the correct answer.

Statement 1 is Correct: The National Institute for Research and Application of Natural Resources to Transform, Adapt and Build Resilience (NIRANTAR) is a collaborative platform under the Ministry of Environment, Forest and Climate Change (MoEFCC). Ecosystem Survey & Analysis is one of its four thematic verticals, and its lead institute is the Botanical Survey of India (BSI), Kolkata. Statement 2 is Incorrect: The Research and Management of Ecosystem Service vertical is led by the Indian Council of Forestry Research and Education (ICFRE), Dehradun, not the Central Zoo Authority (CZA). The CZA is merely a participating institute under this vertical. Statement 3 is Correct: The Capacity Development Support vertical focuses on research, education, and capacity building. The lead institute for this vertical is the Indian Institute of Forest Management (IIFM), Bhopal. Therefore, option B is the correct answer.

Statement 1 is Correct: *Rhynchostylis retusa* (commonly known as the Foxtail orchid) is an epiphytic orchid. It grows on the trunks and branches of trees in open forests, using the host tree for physical support and absorbing moisture from the air, rather than acting as a parasite. Statement 2 is Incorrect: The species is not endemic to North-east India. It has a vast native range across Tropical Asia, including China, Nepal, Sri Lanka, Bhutan, Myanmar, Thailand, Malaysia, Indonesia, and the Philippines. Within India, while it is highly prominent in the North-east, it is also naturally distributed in Odisha, Andhra Pradesh, the Andaman and Nicobar Islands, and several other states. Statement 3 is Correct: It is officially recognized as the State flower of both Assam and Arunachal Pradesh. In Assam, it is culturally significant, known locally as *Kopou Phool*, and is an essential part of traditional Bihu dance attire and local wedding ceremonies. Therefore, option B is the correct answer.

Statement 1 is Incorrect: The Nadi-Sukta of the Rigveda (Rigveda 10.75) lists rivers like the Ganga, Yamuna, Sarasvati, and Sutlej from east to west. It reflects Holocene (historical/human) geography, not Pleistocene geological shifts, which occurred long before the Vedic period. Statement 2 is Incorrect: Robert Bruce Foote is known as the "Father of Indian Prehistory" for discovering India's first Paleolithic handaxe at Pallavaram (Tamil Nadu) in 1863. His explorations focused on stone-age archaeology in South India and Gujarat, not the geological mapping of the Sutlej and Yamuna river shifts. Statement 3 is Correct: The presence of closely related blind river dolphins (*Platanista gangetica minor* in the Indus and *Platanista gangetica gangetica* in the Ganga) in two completely separated basins is a primary biological basis for asserting that these river systems were once physically connected. Geologists propose that during the Pleistocene epoch, a single massive river (the Indo-Brahma or Shiwalik river) connected the modern Indus and Ganga basins. Tectonic uplift (such as the Delhi Ridge) later separated them into distinct drainage systems, causing river avulsion (shifting) where the Yamuna shifted east to join the Ganga and the Sutlej shifted west to join the Indus. Therefore, the correct option is D.

Statement 1 is Incorrect: The Deep Ocean Mission (DOM) is a flagship initiative launched and implemented by the Ministry of Earth Sciences (MoES), Government of India, not the Ministry of Ports, Shipping and Waterways. Statement 2 is Correct: Matsya-6000 is an indigenous manned submersible vehicle developed by the National Institute of Ocean Technology (NIOT). It is specifically designed to carry 3 people (aquanauts) in a titanium alloy sphere to a depth of 6,000 meters for deep-sea exploration, including the study of marine biodiversity and the mining of rare minerals like polymetallic nodules. Statement 3 is Correct: Samudrayaan is India's first manned deep-sea ocean mission and is a primary sub-project under the broader Deep Ocean Mission. Therefore, option B is the correct answer.

Oxygen on Earth mainly comes from photosynthesis, especially by phytoplankton (marine organisms), and oxygen levels differ between air and water. ❌ Statement I is incorrect:
* Oceans (phytoplankton) produce more oxygen than rainforests. ✅ Statement II is correct:
* Marine phytoplankton and photosynthetic bacteria produce about 50% of the world’s oxygen. ❌ Statement III is incorrect:
* Atmospheric air has much more oxygen than surface water; water does not contain several folds higher oxygen than air. So, the correct answer is: B

1. Carabid beetles: Many carabid beetles are predatory, and some species are known to be parasitoids, particularly of other insects.  2. Centipedes: Centipedes are predatory arthropods and not parasitoids. They hunt and kill their prey. 3. Flies: The order Diptera (flies) includes a large number of parasitoid species. For example, Tachinid flies are parasitoids of various insects. 4. Termites: Termites are not parasitoids. They are social insects that primarily feed on wood and other plant matter. 5. Wasps: The order Hymenoptera (wasps, bees, ants) has numerous parasitoid species. Many wasp species are parasitoids, laying their eggs on or in other insects. _Therefore, parasitoid species are found in Carabid beetles, Flies, and Wasps._

Fig-Wasp Mutualism: Figs and fig wasps share an obligate mutualistic relationship, meaning they are entirely dependent on each other for survival and reproduction. Fig wasps are the only insects that can pollinate fig trees, and fig trees are the sole source of food and shelter for developing fig wasps. Highly Specialized Pollination: The fig fruit (technically a syconium) has its flowers enclosed within. Female fig wasps enter the syconium through a tiny opening called the ostiole. They lay eggs inside and pollinate the flowers in the process. Coevolution: This intricate relationship is a classic example of coevolution, where two species have evolved together over millions of years, with each species' adaptations influencing the other's. _The other options are incorrect:_ * Mahua (B): It is pollinated by various insects and even bats. Mahua (Madhuca indica) is found in the dry deciduous type of forests like the Forests of Chhattisgarh and Jharkhand. * Sandalwood (C): It is primarily pollinated by bees and flies. Sandalwood is a dry deciduous forest species native to China, India, Indonesia, Australia, and the Philippines. Sandalwood is listed as Vulnerable in the IUCN Red list. Sandalwood grows as a partial or hemiparasite, relying on the presence of four or five other trees nearby. Beneath the ground, its roots develop a haustorium, an octopus-like structure that attaches to the host tree's roots, drawing water and nutrients from them.  * Silk cotton (D): It is pollinated by bats and birds. The Silk Cotton Tree is a tropical deciduous tree native to the Indian subcontinent and other parts of Southeast Asia. It produces a capsule that, when ripe, contains white fibres like cotton.

Congo Basin Peatlands: The Congo Basin in Central Africa is home to the world's largest tropical peatland complex. This vast peatland stores an immense amount of carbon, estimated to be equivalent to about three years of global fossil fuel emissions.  Importance of Peatlands: Peatlands are a critical carbon sink. They store more carbon than all the world's forests combined. When peatlands are drained or degraded, this stored carbon is released into the atmosphere, contributing to climate change. The Republic of Congo, the Democratic Republic of Cong and Indonesia are parties to the Brazzaville Declaration, aimed at protecting the Cuvette Centrale region in the Congo Basin, the world’s largest tropical peatlands, from unregulated land use and preventing its drainage and degradation.  _Other Options:_  * Amazon Basin: While the Amazon is known for its vast rainforests, it is not the primary location of the world's largest tropical peatland. * Kikori Basin: The Kikori Basin is located in Papua New Guinea and contains significant peatlands, but not the largest tropical peatland complex. * Rio de la Plata Basin: This basin in South America is primarily known for its grasslands and is not associated with major peatland areas.

1. Brazil - Indri: Indris are _lemurs_ found only in Madagascar, not Brazil. So, this pair is incorrect. 2. Indonesia - Elk: Elks are found in North America, Europe, and Asia, but not in Indonesia. This pair is incorrect. 3. Madagascar - Bonobo: Bonobos are found in the Democratic Republic of Congo, not Madagascar. This pair is also incorrect. Therefore, none of the pairs are correctly matched.