The peppered moth witnessed a change in its color and the number at the end of the eighteenth century. The reason behind this was the Industrial Revolution that led to an increase in air pollution. With the increase in air pollution, the dark-colored moths increased in the number. Later, when air pollution decreased, the light-colored moths started to predominate. It was in 1895 that the number of dark-colored moths increased to the maximum.
Diploid and polypeptide cells whose chromosomes have the same allele at a given locus are called homologous with respect to that locus, while those that have different alleles at a given locus are called heterogeneous. The ordered list of loci known for a particular genome is called a gene map.
