Explore BrainMass

Explore BrainMass

    Industrial melanism in peppered moths & selective pressure.

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    In 3-4 paragaphs
    According to the Theory of Evolution, Natural Selection is the mechanism by which evolution occurs.

    The process of Natural selection is based on the following four postulates
    Postulate 1 - Individual members of a population differ from one another in many respects.

    Postulate 2 - At least some of the differences among members of a population are due to characteristics that may be passed from parent to offspring. That is, they are heritable or genetic.

    Postulate 3 - In each generation, some individuals in a population survive and reproduce successfully but others do not.

    Postulate 4 - The fate of individuals is not determined by luck. Instead, an individual's likelihood of survival and reproduction depends on its characteristics. Individuals with advantageous traits survive longest and leave the most offspring, a process known as Natural Selection.

    Choose an animal species. Your goal is to describe the way in which an evolutionary change might occur for a particular characteristic (trait) of that species as a result of natural selection. The characteristic could be something like coloration pattern, length of the limbs, or size of the teeth or beak, or any measurable trait that is inherited.

    The organism you choose should be a real one but the evolutionary change you describe can be real or theoretical.
    Remember: evolution occurs at the level of the population. Individuals do not evolve, populations evolve.

    Explain how the change occurs in terms of the four postulates listed in the book.

    You will describe what the population starts out like at time zero and then what it will look like at a later time, as a result of natural selection. Make sure to explain the process by which the changes occurred.

    What is the selective pressure? Explain why the change might confer more fitness to a particular environment?

    © BrainMass Inc. brainmass.com October 9, 2019, 9:24 pm ad1c9bdddf

    Solution Preview

    The industrial melanism in the peppered moth, Biston betularia, provides the most dramatic evidence of Natural selection. There was a steady rise of industrialization in Europe during the early part of nineteenth century. Thus, the black sooty smoke emitted from industries fell upon the country side and covered the forests and fields with soot. As a result, more than 700 species of larger moths underwent a dramatic change in coloration in regions of heavy industrial activity. Such a change in the coloration is known as Industrial melanism. It can be well studied in peppered moths, Biston betularia.

    During the early part of the nineteenth century only light colored moths were known across England. The body and wing color of the typical peppered moth used to be light with scattered dark markings. In 1948, a local black mutant form of the moth was discovered near Manchester, England. Since that time, the black form of peppered moth, Biston betularia var carbonaria has gradually become more prevalent. As of now, more than 90% of the moths in this region are black. They are more vigorous and viable, and capable of withstanding environmental hardships, and are better adapted to the environment as compared to the wild ...

    Solution Summary

    The solution deals in-depth with an interesting evidence of natural selection namely, industrial melanism among peppered moths, Biston betularia var carbonaria. It also explains the meaning of selective pressure along with the reason as to why the change which occurs as a result of the same confers more fitness to an organism as related to a particular environment.