Chapter 1, Problem 6SA

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.

What is Microevolution? A) The change of a population over several generations B) The history of a species from its origin C) The history of all populations and their descendants

Evolution determines the change in inherited traits over time to ensure survival. There are three variants identified as Variant 1 with high reproductive rate, eats fruits and seeds; Variant 2, thick fur, produces toxins; and Variant 3 with thick fur, fast and resistant to disease. These variants are found in a cool, wet, and soil environment. In time 0 years with cool and wet environment, the population is 50,000 with 10,000 Variant 1, 15,000 Variant 2, and 25,000 of Variant 3. Two thousand years past, the environment remained the same with constant average temperature and rainfall. Variant 1 with a population of 26,000, Variant 2, 35,000, and Variant 3, 62,000. A disease spread throughout the population. However the population increased to 72,000. Determine the percentage increase in the population of the variants.