Free Evolution MCQs with Answers

51. Homologous structures indicate

• A. Convergent evolution
• B. Divergent evolution
• C. No evolutionary relationship
• D. Analogous functions

Explanation: Homologous structures (same origin, different function) indicate divergent evolution from a common ancestor.

52. The bottleneck effect is a type of

• A. Natural selection
• B. Genetic drift
• C. Gene flow
• D. Mutation

Explanation: The bottleneck effect is genetic drift caused by a drastic reduction in population size, reducing genetic diversity.

53. Allopatric speciation requires

• A. Same habitat
• B. Geographic isolation
• C. Polyploidy
• D. Sympatric conditions

Explanation: Allopatric speciation occurs when populations are separated by a geographic barrier, leading to reproductive isolation.

54. Analogous structures result from

• A. Common ancestry
• B. Convergent evolution
• C. Divergent evolution
• D. Vestigial development

Explanation: Analogous structures (different origin, same function) result from convergent evolution, e.g., wings of bats and insects.

55. The modern synthesis combines

• A. Darwin and Mendel
• B. Lamarck and Darwin
• C. Mendel and Morgan
• D. Watson and Crick

Explanation: The modern evolutionary synthesis combines Darwin's natural selection with Mendelian genetics and population genetics.

56. Vestigial organs are

• A. Essential for survival
• B. Reduced non-functional remnants
• C. Newly evolved structures
• D. Only found in embryos

Explanation: Vestigial organs (appendix, coccyx) are reduced remnants of structures functional in ancestors.

57. Gene flow between populations

• A. Increases genetic differences
• B. Decreases genetic differences
• C. Has no effect
• D. Causes speciation

Explanation: Gene flow (migration) decreases genetic differences between populations by exchanging alleles.

58. Punctuated equilibrium proposes

• A. Constant slow change
• B. Rapid change followed by stability
• C. No change over time
• D. Only gradual change

Explanation: Eldredge and Gould's punctuated equilibrium proposes long periods of stability interrupted by rapid speciation events.

59. The main idea in Darwin's Theory of "Origin of species by natural selection" is:

• A. Inheritance of acquired traits
• B. Use and disuse of organs
• C. Species never change
• D. Evolution occurs through gradual accumulation of adaptation through successive generations

Explanation: Darwin argued that individuals vary, that more are born than can survive, and that those better suited leave more offspring, so favourable adaptations accumulate slowly across generations. Inheritance of acquired characters and use and disuse are Lamarck's proposals, offered here as the standard distractors. Fixity of species is the view Darwin overturned.

60. Which of the following best describes "acquired characteristics" according to Lamarckism?

• A. Traits caused by mutation
• B. Traits inherited from parents
• C. Traits developed by use or disuse
• D. Traits selected by nature

Explanation: Lamarck held that an organ strengthens with use and withers with disuse during an individual's own lifetime, and that this change is then passed on. Weismann's germ plasm work disproved the inheritance step, since changes to body cells never reach the gametes. Mutation and natural selection belong to the modern account that replaced it.