Previous Year Questions

QUESTION ID:2

The graph shows the rank-abundance relationships for species in three communities, P, Q and R.

Which one of the following statements is true with respect to the evenness of the three communities?

QUESTION ID:3

The graph shows bird species richness in a large contiguous forest patch and a small adjacent forest fragment, before and soon after the large contiguous forest patch was replaced by an oil palm plantation.

Which one of the following options best explains the pattern shown?

QUESTION ID:4

Honey bees are haplodiploid, which means that the relatedness is, on average, expected to be 0.75 between

QUESTION ID:5

Match the mollusc taxa to their respective orders

QUESTION ID:6

A terrestrial species P is found in both India and West Africa and nowhere else, while a marine species Q is found in the Arabian Sea and the Bay of Bengal. The two species have similar generation times. An ecologist builds haplotype networks based on DNA sequences from these species, where each circle represents one haplotype and each dash (−) represents a mutation. Which one of the following inferences is best supported by the haplotype networks shown?

QUESTION ID:7

Grey langurs found in the southern Western Ghats (SWG) and grey langurs in Sri Lanka (SL) look very similar. Nilgiri langurs (found in SWG) and purple faced langurs (found in SL) also look similar. If allopatry played a role in the early diversification of this group (at point x in the tree), which one of the phylogenetic trees is most likely to be correct?

QUESTION ID:8

Two bird species, A and B, are found on a single mountainside. A is a low-elevation species, found between 500 m and 1500 m Above Sea Level (ASL), while B is a high-elevation species, found between 1000 m and 2000 m ASL. At 1250 m ASL, species A and B have very different bill morphologies, but the bill morphology of species A at 500 m is very similar to the bill morphology of species B at 2000 m ASL. Which one or more of the following explain(s) the difference in bill morphology at 1250 m ASL?

QUESTION ID:9

Which one or more of the following is/are greenhouse gas(es)?

QUESTION ID:10

QUESTION ID:11

Female Anopheles mosquitoes bite humans to get blood. Researchers performed an experiment to study whether females use temperature or scent cues, or both, when locating human hosts. They presented female mosquitoes with membranes kept at different temperatures. Some membranes also had human scent applied to them. The response to each treatment was measured as the percentage of females that landed on the membrane (50 females for each treatment). The table shows the treatments and the corresponding responses

Which one or more of the following inferences is/are supported by these results?

QUESTION ID:12

A phylogenetic tree for the evolution of two pigmentation traits in species of fish is shown for clades X, Y and Z. Genes A and/or B, if mutated, can cause dark pigmentation in the body

Which one or more of the following statements is/are correct?

QUESTION ID:13

In conservation biology, which one or more of the following is/are used to calculate the effective population size, Ne ?

QUESTION ID:14

In the foodweb diagrams shown, R represents the primary producer, C1 and C2 represent intermediate consumers, and P represents the top predator. Which one or more of these diagrams show(s) intraguild predation?

QUESTION ID:15

You are a plant ecologist studying a plant in the genus Veronica. You notice that, at open rocky sites, Veronica grows as a creeper spreading low to the ground, whereas in grasslands, the stem stands upright. You collect seeds from multiple populations in each habitat type and grow them under uniform conditions in a greenhouse. You find that all the plants grown in the greenhouse have stems that stand upright. Which one or more of the following explanations best support(s) your observations?

QUESTION ID:16

One hypothesis for why the tropics have far greater species richness than higher latitudes is that the tropics are relatively aseasonal. Low seasonality can encourage high species richness through which one or more of the following mechanisms?

QUESTION ID:17

The figure illustrates the soil zinc tolerance of the grass species Anthoxanthum along a transect from inside a mine to the middle of a pasture outside the mine

Which one or more of the following processes explain(s) the observed pattern of zinc tolerance in this grass species?

QUESTION ID:18

In a forest, there are tigers, hare, and deer. On a given day, the probability of a tiger hunting a hare is 0.35, a deer is 0.25, and either a hare or a deer is 0.55. The probability of a tiger hunting both a hare and a deer on a given day is __________. (Round off to two decimal places).

QUESTION ID:19

Consider a discrete random variable X that takes values from the set S = {0, 1, 2, 3}, being the number of individuals of a species within a habitat. Consider the probability distribution of X with Pr(X = 0) = 0.15, Pr(X = 1) = 0.25 and Pr(X = 3) = 0.5, where Pr denotes probability. The value of Pr(X = 2) is _______. (Round off to two decimal places)

QUESTION ID:20

There are nine species of Impatiens (balsams) found in laterite plateaus of the northern Western Ghats, each with a distinct colour. If a plateau has exactly 6 species, then the number of possible colour combinations in the plateau is __________. (Answer in integer)