Explain the phenomenon of evolution by natural selection as supported by the variations observed in white winged and dark winged moth populations in England between 1850 – 1920.
Answers
Natural selection acted through the agency of the birds and light coloured moth easily became the prey. So, the dark variety of moth survived better , and left more offsprings and almost nearly replaced the light form . This phenomenon has been called industrial melanism..
Answer:
During the time before industrialisation had occured the no. of white winged moths was more as compared to that of the dark winged moth.
This was because the white winged moths could easily camouflage themselves between the white coloured lichens growing on barks of the trees while the dark winged moths couldn't and hence became an easy prey.
But things changed after industrialisation. Due to increased level of pollutants lichens did not grow anymore or were very few and hence the dark tree barks could be seen more clearly than ever. This changed the things for the moths. Now the dark moths could camouflage while the white winged became the prey.
This was known as industrial melanism.
Though a species might be less in number but none of them were extinct. The balance always exists (#Thanos)..
Hope it helps..
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