No variant os completely wiped out. Explain
in case of the industrial melanism,
before industrialisation begin in England, there were more no. of white winged moths then dark winged or melanised moth because the tree trunks were covered with lichen that were almost white in colour, as a result the predators could predict only the melanised moths.
but after industrialisation begin, there were more no. of melanised moths then white winged moths because the tree trunks were no longer covered with lichens and the predators could easily predict the white winged moths.
but in those areas where industrialisation had not began(in rural areas) there were more counts of white winged moths than melanised moths, but in urban areas where industrialisation had began, there were more count of melanised moths then white winged moths.
these explains the fact that no variant is completely wiped out.
before industrialisation begin in England, there were more no. of white winged moths then dark winged or melanised moth because the tree trunks were covered with lichen that were almost white in colour, as a result the predators could predict only the melanised moths.
but after industrialisation begin, there were more no. of melanised moths then white winged moths because the tree trunks were no longer covered with lichens and the predators could easily predict the white winged moths.
but in those areas where industrialisation had not began(in rural areas) there were more counts of white winged moths than melanised moths, but in urban areas where industrialisation had began, there were more count of melanised moths then white winged moths.
these explains the fact that no variant is completely wiped out.