Evolutionary Biology — DU B.Sc. (Hons.) Zoology Previous Year Question Papers

5. (a) Describe the various pre-zygotic and post-zygotic isolating mechanisms using suitable examples. 12 (b) Mass extinction events can facilitate species diversity, Yes or No? Justify your answer. 3 6. Write short notes on any three of the following : (a) Neo-Darwinism (b) Endosymbiotic theory (c) Geological time scale (d) Kin selection Biology NEP-UGCF (b) Attempt four questions in all. (a) Define the following : 4 (ii) Inbreeding depression (iii) Genetic load (b) Differentiate between the following : 6 (i) Back ground extinction and Mass extinction (ii) Microevolution and Macroevolution (iii) Lamarckism and Darwinism (c) Write one contribution of the following scientists : 2 (i) Raymond Dart (d) Fill in the blanks : 3 (i) Australopithecus showed evidence of (ii) A ......... species consists of a series of neighboring populations that can interbreed with adjacent populations but not with those at the ends. (iii) ......... refers to the reduction in the average fitness of a population due to the presence of deleterious alleles. 2. (a) Explain the process of evolution through natural selection. Discuss the different types of natural selection with suitable examples. 3+9=12 (b) Discuss the role of adaptive resemblance as a driver of frequency dependent selection. 3 3. (a) Explain the biochemical theory of origin of life. Describe in detail the experimental evidence provided by Stanley Miller and Harold Urey in support of this theory. (b) Describe the trends leading to the evolution of modern horse with reference to important fossil records. 9 4. (a) Explain the different ways in which heritable variations contribute to evolution.