- A Lamarck's proposal of inheritance of acquired characteristics was later found by most twentieth-century geneticists to be largely incorrect, despite some renewed interest in related epigenetic mechanisms according to most researchers
- B Lamarck proposed inheritance of acquired characteristics (use and disuse); giraffes stretched necks, offspring born with longer necks; incorrect because acquired physical changes are not encoded in DNA and not inherited
- C Lamarck actually proposed the mechanism of natural selection acting on heritable variation, a concept that Darwin later popularized and published in detail in the majority of cases studied as widely reported in standard practice
- D Lamarck argued throughout his writings that evolutionary change and species transformation rarely occurs within the natural living world, a view later revised significantly under most conditions encountered as frequently observed in practice
Correct answer: B. Lamarck proposed inheritance of acquired characteristics (use and disuse); giraffes stretched necks, offspring born with longer necks; incorrect because acquired physical changes are not encoded in DNA and not inherited
Explanation: Lamarck (1809): organisms change through use/disuse, and these changes are inherited (soft inheritance). Example: giraffe stretches neck → neck gets longer → offspring inherit longer neck. Incorrect because: somatic (body) cell changes are not transmitted to germline (Weismann barrier). Mendel and later molecular genetics confirmed only DNA changes in reproductive cells are inherited.
Concept context
Origin of life, Darwin's theory, natural selection, speciation, and evidence for evolution.