University:
University of Cincinnati
Course:
BIOL 2084C | Evolution and Ecology
Academic year:

2023
Views:

297

Pages:

2
Author:

Walker Whitney

Engagement Rock Pocket Mouse Key Performance Expectations (Standards): Use mathematical representations (data tables/graphs) to support explanations of how natural selection may lead to increases and decreases of specific traits in populations over time. Construct an explanation based on evidence that describes how genetic variations of traits in a population increase some individuals’ probability of surviving and reproducing in a specific environment. Essential Question: How do traits in a population change over time? Engagement KEY 1. Population: All of the individuals of the same species that live in a particular area. 2. Natural selection: The process in nature by which organisms with traits that help them survive, reproduce more and pass on those traits to their offspring. 3. Mutation: A gene mutation is a permanent change in the DNA sequence that makes up a gene. A mutation could change the traits in the organism. 4. Variation: Members of the same species population with different traits. 5. Evolution: Gradual changes in traits in a species population from one generation to the next and the evolution of different species from a common ancestor over many generations. 6. Trait: a genetically determined characteristic passed on from parents to offspring (hair color, eye color, skin color) 7. Adaptation: a trait or behavior in a species population that makes it better suited to its environment. Organisms are BORN WITH them. (Adaptations provide advantages) 8. Speciation: The evolution of a new species from an existing species. 9. Why do the pocket mice in the dark lava environment have dark fur on top and white underbellies? The darker fur on the top of their bodies provides camouflage so predators won’t see them. The mice’s underbellies are white because there’s no selective pressure for it to be dark; the predators come from above so it doesn’t matter what color the bellies are. 10. What causes the overall differences in mouse fur color (big picture)? The differences in mouse fur color are caused by natural selection. The environment “selects” those individuals with the most favorable traits to survive and reproduce. 11. How does a dark mouse appear in a population of light mice? Gene mutations cause the darker mice. 12. Are mutations good or bad? Explain. Mutations are favored, rejected, or neutral depending upon an organism’s environment. (Darker fur is favorable in the dark environment and harmful in the light.) 13. How do you get a population of dark colored mice? In dark environments, the dark colored mice have an advantage; they survive better and have more offspring. A small advantage can lead to big changes in the population very quickly. Mutations that increase the chance of survival of an organism can become much more common in a population. 14. Did the mice on each of the dark lava flows have the same mutation? No. Different mutations can cause the same phenotype (trait). Evolution repeats itself in different environments. 15. Is evolution a random process? Evolution is not a random process. Mutations are random, but natural selection is not random. The survival and reproductive success of an individual is directly related to how their traits help them to function and survive in their environment.