Select the correct statement from the following given options.
1. Darwinian variations are small and directionless
2. Fitness is the end result of the ability to adapt and gets selected by nature
3. All mammals except whales and camels have seven cervical vertebrae
4. Mutations are random and directional
Jurrassic period of the Mesozoic era is Characterised by
1. radiation of reptiles and origin of mammal-like reptiles
2. dinosaurs become extinct and angiosperms appear
3. flowring plants and first dinosaurs appear
4. gymnosperms are dominant plants and first birds appear
Which one of the following is regarded as the direct ancestor of modern man?
1. Homo erectus
2. Ramapithecus
3. Homo habilis
4. Cro-magnon man
Which one of the following sequences was proposed by Darwin and Wallace for organic evolution?
1. Variations, natural selection, overproduction, constancy of population size
2. Overproduction, variations, constancy of population size, natural selection
3. Variations, constancy of population size, overproduction, natural selection
4. Overproduction, constancy of population size, variations, natural selection
Industrial melanism is an example of
1. defensive adaptation of skin against ultraviolet radiations
2. drug resistance
3. directional selection due to smoke from industries
4. protective resemblance with the surroundings
The homologous organs are those that show similarity in
1. size
2. origin
3. function
4. appearance
The occurrence of endemic species in South America and Australia is due to
1. Extinction of these species from other regions
2. Continental separation
3. No terrestrial route to these places
4. Retrogressive evolution
Genetic drift is change of
1. gene frequency in same generation
2. appearance of recessive genes
3. gene frequency from one generation to next
4. None of the above
Thorn of Bougainvillea and tendril of Cucurbita are examples of
1. analogous organs
2. homologous organs
3. vestigial organs
4. retrogressive evolution
Adaptive radiation refers to
1. adaptations due to geographical isolation
2. evolution of different species from a common ancestor
3. migration of members of a species to different geographical areas
4. power of adaptation in an individual to a variety of environments