Study the mechanisms of evolution, including natural selection and genetic variation. Review key concepts and test your understanding with practice questions.
Thomas Malthus's work on population growth and resource limitation influenced Darwin's concept of natural selection.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Lamarck's theory of inheritance of acquired characteristics has been rejected in favor of Darwin's theory of natural selection.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Mutations do not always result in beneficial changes; they can also be harmful or neutral.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Alfred Wallace independently arrived at the theory of natural selection while working in the Malay Archipelago.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Cyanobacteria were the first organisms to release oxygen through photosynthesis, transforming Earth's atmosphere.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Lamarck's theory of use and disuse is not widely accepted; Darwin's theory of natural selection is the accepted mechanism of evolution.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
The Hardy-Weinberg Principle states that allele frequencies remain stable unless affected by evolutionary forces like mutation or selection.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Hugo de Vries suggested that mutations cause large, sudden evolutionary changes, a process he termed 'saltation'.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Lamarck's theory proposed the inheritance of acquired traits, not the survival of the fittest, which is Darwin's concept.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Thick-shelled eggs prevented desiccation, enabling reptiles to dominate terrestrial environments.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
Lobefin fishes are considered direct ancestors of modern-day amphibians due to their limb-like fins.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
The Cretaceous-Paleogene extinction marked the end of large reptiles (dinosaurs) and the rise of mammals.
Ref: NCERT Class 12 Biology Chapter 6: Evolution Darwinism Lamarckism and Modern Synthetic Theory
