Question

In the 1850s, before industrialisation, it was observed that there were more white-winged moths on trees than dark-winged moths. But the proportion was reversed (There were more dark-winged moths in the same area) in ____________
A. 1920.
B. 1935.
C. 1928.
D. 1865.

Answer 1

Hint: Moths are a paraphyletic group of insects containing all members of the order Lepidoptera that are not butterflies, with moths that make up most of the order. There are probably about 160,000 species of moth.

Complete step-by-step answer:
Moths are quiet creatures. They never attack or try to harm people and they just keep to themselves. They never sting or bite, unlike spiders, wasps, or ants. They do cause financial damages and are certainly a nuisance at home. The number of light-winged moths was a lot more during a pre-industrialised period than dark-winged moths were as it reversed into the post-industrialised period. In the pre-industrialised period, the tree trunks have been covered with dense white growth of lichens. Therefore, the light-coloured were not spotted by the predator and their number was increased, however, dark-coloured moths were captured, and their number was reduced.
During the post-industrialisation period i.e. in 1920, the tree trunks became dark because of industrial smoke. Hence, the dark-coloured moths were not captured by the predators and their number was increased although the light-coloured moths were captured and their number reduced. In a mixed population those moths that are better adapted camouflaged to the changing environment survive and increase the population size.
Therefore the correct answer is option A.

Note: Moths play a key role in the food webs and are an essential food item for mammals, songbirds, and other insects. Moths also are significant pollinators, especially those that are active after dark, when several other pollinating animals have settled down for the night.