Evolution Biologists define evolution as the change in the frequency of alleles (variations of a gene) in a population. Consider the following situation: Two colors of grasshoppers-brown and red-result from the two variations (alleles) of the color gene in this species. These grasshoppers live in two areas: an area with brown soil, and on an adjacent mountain with reddish soil. All the grasshoppers in both areas were accidentally killed by a fire. Ecologists re-introduced 1000 red and 1000 brown grasshoppers into each of the two soil areas. And, grasshoppers are a great food source for any bird that can catch them. 1. What do you think the ecologists discovered when they returned to the experimental sites five years later? 2. What factor controls the actual color of a grasshopper? 3. What determines the color frequency of grasshoppers in the two soil areas? 4. Is there only one direction of change during evolution? Explain your answer.

Evolution Biologists define evolution as the change in the frequency of alleles (variations of a gene) in a population. Consider the following situation: Two colors of grasshoppers-brown and red-result from the two variations (alleles) of the color gene in this species. These grasshoppers live in two areas: an area with brown soil, and on an adjacent mountain with reddish soil. All the grasshoppers in both areas were accidentally killed by a fire. Ecologists re-introduced 1000 red and 1000 brown grasshoppers into each of the two soil areas. And, grasshoppers are a great food source for any bird that can catch them. 1. What do you think the ecologists discovered when they returned to the experimental sites five years later? 2. What factor controls the actual color of a grasshopper? 3. What determines the color frequency of grasshoppers in the two soil areas? 4. Is there only one direction of change during evolution? Explain your answer.

Human Anatomy & Physiology (11th Edition)

11th Edition

ISBN:9780134580999

Author:Elaine N. Marieb, Katja N. Hoehn

Publisher:Elaine N. Marieb, Katja N. Hoehn

Chapter1: The Human Body: An Orientation

Section: Chapter Questions

Problem 1RQ: The correct sequence of levels forming the structural hierarchy is A. (a) organ, organ system,...

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