Ecosystems and Biodiversity Questions and Answers

Answer: A

The region is the Western Ghats.

The Western Ghats, along with Sri Lanka, form one of the world's biodiversity hotspots and are a UNESCO World Heritage Site. Their wet evergreen forests hold a very high proportion of endemic species, especially of amphibians, reptiles, fishes and flowering plants, which is why they are cited as the Indian region richest in endemic biodiversity.

The Andaman and Nicobar Islands also have notable endemism but on a much smaller species pool, and the Deccan Plateau and Gangetic Plains are far poorer in endemics.

Answer: C

The Man and the Biosphere Programme was initiated by UNESCO.

UNESCO launched the Man and the Biosphere (MAB) Programme in 1971 to improve relations between people and their environment. Under it, biosphere reserves are designated, with a core zone, buffer zone and transition area.

UNEP is the UN Environment Programme, set up in 1972; ICSU is the International Council for Science; and IUCN is the conservation union. None of them launched MAB.

Answer: B

Ex-situ conservation can be done by botanical gardens.

Ex-situ means off-site: species are conserved outside their natural habitat, in botanical gardens, zoos, seed banks, gene banks and tissue culture collections.

National parks, protected areas and biosphere reserves conserve species in their natural habitats, which is in-situ conservation.

Answer: C

The interaction is commensalism.

In commensalism one species benefits and the other is neither helped nor harmed: for example, an orchid growing on a tree gains a place in the light without harming the tree, and cattle egrets feed on insects disturbed by grazing cattle.

In parasitism one benefits at the other's expense, and in competition both are harmed. Camouflage is an adaptation for concealment, not an interaction between two species.

Answer: C

The State Bird of Madhya Pradesh is the Paradise flycatcher.

The Asian (Indian) paradise flycatcher, known locally as Dudhraj, was adopted as the state bird in 1985. The adult male is striking, with a black crested head and very long white or rufous tail streamers, and the bird is found in the forests of the state.

The peacock is the national bird of India, not the state bird. The moorhen and the parrot are common birds but have not been adopted as Madhya Pradesh's state bird. For reference, the state animal is the barasingha (hard-ground swamp deer) and the state tree is the banyan.

Answer: A

The pyramid of energy is always upright.

The pyramid of energy shows the flow of energy through successive trophic levels. At each transfer most of the energy is lost as heat in respiration, and only about 10 percent passes to the next level (Lindeman's ten percent law). Energy at each level is therefore always less than at the level below, so the pyramid can never be inverted.

Pyramids of number and biomass can be inverted, for example a single tree supporting many insects, or phytoplankton in the sea, which is the trap in the other options.

Answer: B

The one that is not a biodiversity hotspot of India is Naro Hills.

Conservation International's list of 36 global hotspots includes four regions that cover parts of India: the Himalaya, Indo-Burma (the north-east), the Western Ghats and Sri Lanka, and Sundaland, which includes the Nicobar Islands.

So Himalayas, Sundaland and Western Ghats are all accepted hotspots touching India. 'Naro Hills' is not on the list, which makes it the odd one out.

Answer: C

The key gives the Marine ecosystem as the most stable.

The oceans are the largest ecosystem on Earth. Their enormous volume of water changes temperature slowly, salinity and chemistry stay nearly constant, and food webs are vast and interconnected. These features buffer marine communities against short-term disturbance, which is why textbooks commonly name the ocean as the most stable ecosystem.

Deserts and grasslands face extremes of temperature and rainfall and are easily disturbed by drought, grazing and fire. Forests are rich and fairly stable, but they are still exposed to fire, clearing and climatic swings on land, so they are not ranked above the ocean in this comparison.

Answer: B

The decline of energy along a food chain is explained by the Second law of thermodynamics.

The second law states that in every energy transformation some energy is degraded into heat that can no longer do useful work. At each trophic level, organisms spend most of the energy they take in on respiration and lose it as heat, so only about 10 percent passes to the next level (Lindeman's ten percent law). That is why energy flow narrows from producers to top carnivores.

The first law says energy is neither created nor destroyed; it explains why the total is conserved, not why usable energy declines. Newton's second and third laws deal with force and motion, not energy flow in ecosystems.

Answer: B

The figure is 100 km².

Under IUCN Red List criterion B1, a species qualifies as Critically Endangered when its extent of occurrence is estimated to be less than 100 km², together with other conditions such as severe fragmentation or continuing decline. The thresholds rise with the lower categories: less than 5,000 km² for Endangered and less than 20,000 km² for Vulnerable.

50, 150 and 200 km² are not thresholds used in the criteria. (The separate area of occupancy criterion, B2, uses 10 km² for Critically Endangered.)