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Evolution by Natural Selection Example

SCI206-0802B-24 Biology
Assignment Name: Unit 4 Discussion Board
Deliverable Length: 3-4 paragraphs
Details: 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 (listed in your textbook on page 288):
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?

Solution Preview

This question is quite timely given the present atmosphere of climate change. Changes to the climate will have huge effects on all of the World's species which will spur evolution in numerous populations, particularly in areas at the ends of a species range. Below I've briefly outlined one example for you. To complete this assignment you will need to expand on this answer in the places I've noted or chose another species and follow the outline I provide below.

The theoretical Selective Pressure: Global warming has shifted populations of trees in the North East United States such that tree species that used to be at the Northern border of their ...

Solution Summary

In this solution I theorize the adaptations that could be made by a butterfly species as a result of a warming environment. I examine the postulates below to address the question thoroughly.
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.

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