List of practice Questions

A population shows exponential growth of the form \( N_t = N_0 e^{rt} \) where \( N_t \) is the population at time \( t \), \( N_0 \) is the initial population size, and \( r \) is the rate of increase. If \( r = 0.1 \), then the doubling time for this population is \(\underline{\hspace{1cm}}\) (Round off to two decimal places.)
At a locus with two alleles A1 and A2, the genotype A1A1 produces white flowers, A2A2 produces red flowers, and A1A2 produces pink flowers. For a population in Hardy-Weinberg equilibrium, the frequency of red flowers is 0.25. If the white-flowered plants are removed, and all pink and red flowered-plants in this population are randomly crossed amongst each other, the frequency of white flowered plants in the next generation will be \(\underline{\hspace{1cm}}\) (Round off to two decimal places.)
A gene duplication event in an organism results in two copies of a gene. Which one (or more) of the following outcomes is/are possible for the duplicated copy?
The egg-laying mammal, platypus, is known for its ability to inject venom by stabbing with spurs on its hindlimbs. Which one (or more) of the following statements supports the hypothesis that venom in this species is used for intrasexual competition?
Behavioural ecologists exploring a newly discovered island find 20 new species of terrestrial lizards. Males of these species have a dorsal ridge that varies in size from large in some species to entirely lacking in others. The scientists hypothesise that dorsal ridges in males evolved by runaway sexual selection stemming from sensory bias in females. Which one of the following would provide the necessary evidence to support this hypothesis?
Which one of the following represents the correct chronological order of geological periods (from oldest to most recent)?
Consider 1000 terrestrial species that have geographical ranges of different shapes and sizes. If the Earth were entirely covered by land (no oceans), and the ranges of these species were overlaid on the surface of the Earth at random, which one of the following patterns is expected?
A researcher measures the abundance of a tree species in 10 plots in each of two habitats. She tests for differences in abundance between the two habitats using an ANOVA. The results from the ANOVA are as follows: \[\begin{array}{rl} \bullet & \text{Mean abundance in habitat A = 30 trees} \\ \bullet & \text{Mean abundance in habitat B = 50 trees} \\ \bullet & \text{F-statistic (on 1 and 18 degrees of freedom) = 6.04} \\ \bullet & \text{P-value = 0.02} \\ \end{array}\] Here, a P-value of 0.02 means that:
Which one of the following statements is INCORRECT with respect to the tree of life?
A bird species has an annual survival probability of 0.30. While sampling the population of this species, the probability that any individual is captured in a given year is 0.40. A bird is captured, tagged, and released in Year one. The probability that it is re-captured in Year two is \(\underline{\hspace{0cm}}\) (Round off to two decimal places.)
Sex ratio at birth is biased towards females in a mongoose population. If the probability of having a daughter is 0.7 in this population, and if sex determination of each offspring is an independent event, then the probability that a female with a litter of four offspring has at least one son is \(\underline{\hspace{0cm}}\) (Round off to two decimal places.)
Homing pigeons can perceive the pattern of polarized light in the sky (which depends on the position of the sun relative to the earth). This enables homing pigeons to orient and navigate home if released in any location. One can reset their biological clock in captivity by artificially controlling the light conditions. If you acclimatize a pigeon to a new lighting cycle with "sunrise" at 6 PM and "sunset" at 6 AM, instead of 6 AM sunrise and 6 PM sunset that naturally occurs, the bird will be clock-shifted by 12 hours within a few days. Suppose you release two birds, a normal bird (N) and a 12-hr clock-adjusted bird (C), 30 km East of their home at 6 AM. In which direction will each bird fly?
Demographic stochasticity introduces random variation in population growth because
According to the MacArthur – Wilson equilibrium model of island biogeography, which one (or more) of the following factors affect(s) extinction rate on an island?
Rising temperature due to global warming can stimulate decomposition of organic matter and release CO\(_2\) into the atmosphere. This is an example of
Ant-mimic spiders of the genus Myrmarachne are known for which one of the following evolutionary phenomena?
Grazing by large mammalian herbivores can have a strong influence on ecosystem structure, and can cause ecosystems to transition between alternative states over decades. Which one of the following transitions can result from grazing?
The effective population size of a sexually reproducing, diploid, animal species will be highest when the sex ratio (number of reproducing males / number of reproducing females) is
The theory of evolution by natural selection was proposed by which one (or more) of the following?
Which one of the following mammalian DNA regions exhibits the highest level of sequence variation?
Which one of the following makes a species most vulnerable to extinction?
Two sister species of bulbuls have non-overlapping distributions. One is distributed in India and the other in Sri Lanka. Which of the following modes of speciation is the most parsimonious explanation for this pattern?
In an Arctic Ocean food chain, killer whales feed on sea otters, which feed on sea urchins, which in turn feed on kelp (a type of seaweed). An increase in the abundance of killer whales causes sea otter abundance to decline, leading to higher sea urchin densities, which in turn reduces the abundance of kelp. Which of the following terms describes this phenomenon?
Listed below are hypotheses for the evolution of monogamy. Which one of these is NOT based on the concept of individual selection?
Of the following, which one is the most direct measure of Darwinian fitness?