PATTERNS OF EVOLUTION STATIONS

Transcription

1 PATTERNS OF EVOLUTION STATIONS

2 STATION 1 Vocabulary Review: GIVE AN EXAMPLE OF EACH: 1. Stabilizing selection 2. Directional selection 3. Disruptive selection

3 STATION 2 SKETCH AND LABEL EACH GRAPH

4 STATION 3 ANSWER BOTH QUESTIONS IN COMPLETE SENTENCES: 1. What types of individuals in a population are represented by the two ends of a bell curve? 2. If a cow develops a preference for eating white four o clock flowers and ignoring pink and red four o clock flowers, what type of selection is being demonstrated?

5 STATION 4 A population of birds, with various size beaks, eats seeds. Small seeds can be eaten by birds with small beaks. Larger, thicker seeds can only be eaten by birds with larger, thicker beaks. Suppose there is a shortage of small seeds but there are still many large seeds. 1. Draw a curve to show how the distribution of beak sizes might change as a result of selection in this new environment.

6 STATION 5 A population of birds, with various size beaks, eats seeds. Small seeds can be eaten by birds with small beaks. Larger, thicker seeds can only be eaten by birds with larger, thicker beaks. Suppose there is a shortage of small seeds but there are still many large seeds. 1. Which birds in this population have the highest fitness? 2. Explain how natural selection could lead to the change you predicted.

7 STATION 6 Suppose there is a population of rabbits. The color of the rabbits is governed by two incompletely dominant traits: black fur represented by B and white fur represented by b. A rabbit with the genotype of BB would have a phenotype of black fur, a genotype of Bb would have gray fur (a display of both black and white) and a genotype of bb would have a phenotype of white fur. 1. What type of selection would occur if this population migrated to an area that had very dark rocks as well as white colored stone?

8 STATION 7 Suppose there is a population of rabbits. The color of the rabbits is governed by two incompletely dominant traits: black fur represented by B and white fur represented by b. A rabbit with the genotype of BB would have a phenotype of black fur, a genotype of Bb would have gray fur (a display of both black and white) and a genotype of bb would have a phenotype of white fur. 1. Draw a curve to show how the distribution would change if a population migrated to an area that had very dark rocks AND white colored rocks.

9 STATION 8 In humans, birth weight can be represented by a typical bell curve. Babies of low weight lose heat more quickly (surface to volume ratio) and get ill from infectious disease more easily, whereas babies of large body weight are more difficult to deliver through the pelvis. 1. Which type of selection would most likely occur?

10 STATION 9 In humans, birth weight can be represented by a typical bell curve. Babies of low weight lose heat more quickly (surface to volume ratio) and get ill from infectious disease more easily, whereas babies of large body weight are more difficult to deliver through the pelvis. 1. Draw a curve that represents the distribution in birth weight size, based on likelihood of survival.

11 STATION 10 The evolution of the peppered moth over the last two hundred years has been studied in detail. Originally, the vast majority of peppered moths had light coloration, which effectively camouflaged them against the light-colored trees and lichens upon which they rested. However, due to widespread pollution during the Industrial Revolution in England, many of the lichens died out, and the trees which peppered moths rested on became blackened by soot, causing most of the light-colored moths to die off due to predation. At the same time, the darkcolored moths flourished because of their ability to hide on the darkened trees. Since then, with improved environmental standards, light-colored peppered moths have again become common. 1. Which type of selection is illustrated by the peppered moth s during the Industrial Revolution?

12 STATION 11 The evolution of the peppered moth over the last two hundred years has been studied in detail. Originally, the vast majority of peppered moths had light coloration, which effectively camouflaged them against the light-colored trees and lichens upon which they rested. However, due to widespread pollution during the Industrial Revolution in England, many of the lichens died out, and the trees which peppered moths rested on became blackened by soot, causing most of the light-colored moths to die off due to predation. At the same time, the dark-colored moths flourished because of their ability to hide on the darkened trees. Since then, with improved environmental standards, light-colored peppered moths have again become common. 1. Draw a curve that represents the current distribution of moths.

13 Station What is the definition of fitness? (as it relates to natural selection) 2. Give an example of 3 different organisms and what makes them fit?

14 STATION Write an example situation that shows natural selection taking place. Should be at least 2 sentences. Be sure to include what trait is favored. This picture is a joke, do not use this as your example