Class 12th Biology 2017 Set2 Delhi Board Paper Solution
How do the observations made during moth collection in pre and post-industrialised era in England support evolution by natural selection?
Natural selection is the key concept of Darwin’s theory of evolution explained by Charles Robert Darwin.The organisms which adapt well in the environment will be selected by nature and will survive more in nature. This is called natural selection.
An interesting observation supporting evolution by natural selection comes from England.
Pre-industrialisation: In 1850, in a collection of moths it was observed that, there were more white winges moths on trees than dark winged or melanised moths.Due to less pollution, light trunk of trees were there due to lechen. On light background white-winged moths were not visible.
Post-industrialisation: In the collection carried out from the same area but after industrialisation in 1920 there were more dark-winged moths, the proportion was reversed. This was all due to air pollution.
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