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The peppered moth ('''''Biston betularia''''') is a temperate Species of Night-flying Moth often used by educators as an example of Natural Selection (see Theory Of Evolution , Industrial Melanism ). ECOLOGY AND LIFE CYCLE See Also: peppered moth ecology In Britain, the Peppered Moth is univoltine (i.e. it has one generation per year), whilst in south-eastern North America it is bivoltine (two generations per year). The Lepidoptera n Life Cycle consists of four stages; ova (eggs), several Larva Instar s (caterpillars), Pupae and Imagines (adults). During the day, the moths cryptically rest on trees, where they are predated by birds. GENETICS See Also: peppered moth genetics The are several melanic and non-melanic morphs. In Britain, the typical white speckled morph is known as f. ''typica'', the melanic morph is f. ''carbonaria'' and the intermediate Phenotype is f. ''insularia''. These are controlled genetically. At present the biochemistry of the melanism remains unknown, though it should be possible for it to be elucidated. EVOLUTION DEBATE See Also: peppered moth evolution The first carbonaria morph was recorded by Edleston in Manchester in 1848, and over the subsequent years it increased in frequency. This evolution was attributed to Natural Selection (i.e., too fast to be due to Genetic Drift ), though the increase was not monitored very effectively. Predation experiments (see below) particularly by Bernard Kettlewell established that the agent of selection was birds who predated on the f. ''carbonaria'' morph. The Clean Air Act s reduced levels of pollution, and ''typica'' morph frequency has increased, again generally seen as an example of natural selection. A similar process was reported in North America . PREDATION EXPERIMENTS See Also: peppered moth predation experiments Experiments to show differential Bird Predation in the wild have been conducted, notably by Bernard Kettlewell , who in 1953 and 1955 conducted classic experiments mark-release-recapture experiments. Later experiments have shown that was qualitatively correct. ALTERNATIVE THEORIES See Also: peppered moth alternative theories Alternative theories to explain industrial melanism were proposed during the 1920s and 1930s. Particularly notable was the phenotypic induction hypothesis of J.W. Heslop-Harrison, who proposed that industrial pollutants could induce mutations in the peppered moth. The quality of the original science was poor. Later some scientific dissenters have criticised the acceptance of the peppered moth story. In particular, Sargent ''et al'' (1998) argued for a developmental induction hypothesis, Cook, Grant and Majerus have all argued that Sargent ''et al'' CREATIONISM See Also: creationism and the peppered moth Beginning in 1998, the traditional peppered moth story has been criticised by several people, but most prominently by Creationists . "All the peppered-moth pictures were staged," said biologist Jonathan Wells , a senior fellow at the Discovery Institute . "Scientists have known since the 1980s that the moths do not normally rest on tree trunks." There is no standing scientific evidence to support this position. FURTHER READING
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