What is a key stone species ?

• A rare species that has minimal impact on biomass and on other species in community

• A dominant species that constitutes a large proportion of biomass, which affects many other species

• A common species that has plenty of biomass, yet has a fairly low impact on the community's organization

• A species which makes up only a small proportion of the total biomass of a community, yet has a huge impact on the community's organization and survival

In which of the following population, genetic drift operates?

• Island

• Smaller

• Larger

• Continental

Allopatric speciation is due to :

• geographical separation of population

• hybridization between closely related species

• migration of the members of a species from one to other population

• both (b) and (c)

Lichens are important in the studies on atmospheric pollution because they

• can grow in polluted atmosphere

• can readily multiply in polluted atmosphere

• efficiently purify the atmosphere

• are very sensitive to pollutants like sulphur dioxide

The scientific name of Java man is

• Homo habilis

• Homo sapiens neandarthalensis

• Homo erectus erects

• Australopithecus bisei

Evolutionary convergence is characterized by:

• development of characteristics by random mating

• replacement of common characteristic in different related groups

• development of dissimilar characteristics in closely related groups

• development of a common set of characteristics in groups of different ancestry

Which is not applicable to the biological species concept

• Hybridization

• Natural population

• Reproductive isolation

• Gene pool

What are poikilothermic animals?

Which is the closest pet of human being ?

• Cat

• Cow

• Dog

• Buffalo

Darwin finches are related to which of the following evidences ?

• Fossils

• Embryology

• Anatomy

• Geographical distribution