6.3.1: Theory of evolution (biology only)
Not started yet — this one needs some love.
Charles Darwin proposed the theory of evolution by natural selection after observations, experimentation, discussion, and developing knowledge of geology and fossils.
Individual organisms within a particular species show a wide range of variation for a characteristic.
Individuals with characteristics most suited to the environment are more likely to survive to breed successfully.
The characteristics that have enabled these individuals to survive are then passed on to the next generation.
Darwin published his ideas in On the Origin of Species in 1859.
Darwin’s theory was controversial because it challenged the idea that God made all the animals and plants that live on Earth.
Darwin’s theory was only gradually accepted because evidence was limited and the mechanism of inheritance and variation was not known until 50 years after publication.
Lamarck’s theory was mainly based on the idea that changes during an organism’s lifetime can be inherited, but in the vast majority of cases this cannot occur.
Common exam mistakes
Darwin’s theory is natural selection, not Lamarck’s idea that acquired changes are usually inherited.
Do not write that individual organisms choose to evolve; natural selection acts on existing variation.
Darwin’s theory was only gradually accepted because evidence was limited and the mechanism of inheritance was not known.
Evolution needs species or populations changing over generations, not one organism changing during its lifetime.