A biologist once collected sparrows that had been killed in a severe ice storm. His analysis...

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A biologist once collected sparrows that had been killed in a severe ice storm. His analysis revealed that the dead birds were more likely to have either longer or shorter wings than average. In essence, the birds with average-sized wings were doing better, just like they had before the ice storm for many generations. (a) In one sentence state whether wing size is staying the same each generation or whether it is changing. (b) What kind of selection is this? Hints: "Natural selection" and "adaptation" are not correct answers. The correct answer for can be found in the "Details of Natural Selection" section of the lecture, especially the part on the direction of selection.You should focus on the fact that average wing size is found one generation after another.(c) What could account for this type of selection? Explain why the birds with average wings do better. Hints: Provide specific reasonswhy birds with long and short wings do worse. For example, if I was analyzing the size of finch beaks, I might say that birds with smaller beaks would not be unable to crack open seeds during a drought.

Charles Darwin waited a long time to publish his theory of natural selection after he developed the idea. Why was such an idea so controversial? What factors were present in society during his lifetime that made the introduction of evolution theory so difficult? Hints:Make sure you reviewthe Historical Backgroundonline lectures and read the textbook on the background as well, especially the part about the barriers to the introduction to evolutionary theory. You should identify and describe the three factors outlined in the class materials and explain why Darwin's theory conflicted with them.

Part (1): The study guide for this module has an example of how one would describe the evolution of a particular trait in the Adaptation Exercise on page 5. What kind of animal is described in this example? Part (2):South African bullfrogs are quite large, weighing up to four and a half pounds. When disturbed, they can inflate their bodies. (a) Provide a reason for WHY the inflation trait evolved. What was the evolutionary purpose of the trait? (b) Using the same type of evolutionary logic in the "answer" to in the Adaptation Exercises, explain HOW the inflation trait may have evolved.Hints: Do not rely on outside information since it will not be particularly helpful. The goal is for you to apply evolutionary logic (which you develop based upon what you have learned so far) to the question. (Attached is the study guide to reference and textbook chapter)

anthropology-u2hzidit.pdf selection-vbdsv00t.pdf study-guide-module-1-1-2c4zlbmj.pdf

Perla · Accepted Answer

Discussion: Biology
1) A) The immediate observation is that the dead sparrows either do have larger or smaller wings than average. Average sized wings sparrows are doing better than those with shorter or longer wings in general.  This indicates that the wing size is a particular characteristic that is detrimining the life of the sparrows, both the long wings and shorter wings are creating problems of survival for the sparrows, only those that are right fit of average size are surviving. Hence the question is that the average wing size sparrows are surviving and the rest are getting extinguished from time to time. So the change is wing size is constrained.
B) Average wing size is found from one generation to the other and hence it is a case of “stabilizing selection”, all the variants of this feature allele got reduced in the course of time due to the pressures from the environment.
C) Environmental pressures are the main causes of extinction of the other variants (allele is eliminated the fitter is prevailed) . The key reason for this tendency can be that the larger wings are making it vulnerable to the storm impacts etc;

A biologist once collected sparrows that had been killed in a severe ice storm. His analysis revealed that the dead birds were more likely to have either longer or shorter wings than average. In...

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