Microevolution: Changes in Populations

Microevolution

PART 1: EVOLUTION 101

--Go to http://evolution.berkeley.edu/evosite/evo101/IVMicroevolution.shtml and proceed to the definition of microevolution page.

1. How do the authors of this page define microevolution?

They described microevolution as an evolution on a small scale within a single population

2. How do they define a population?

They described population as a group of organisms that interbreed with each other, that is they all share a gene pool.

--Read the section “Mechanisms of Microevolution”

3. Summarize each of the 4 mechanisms of microevolutionary change that are discussed.

Migration-brown beetles could have migrated with population of green beetles making the genes for brown beetles more frequent in green beetle population.
Mutation-could cause parents with genes for bright green coloration to have off spring with a gene for brown coloration, making the genes for brown coloration more frequent in the green population
Genetic Drift-the different chances you have in order to have off springs, and the chances change from generation to generation
Natural Selection- when a selection of beetles (green) are easier to be seen by predators and they are eaten which lead to more brown beetles and the generation next with more brown beetles that before.

--Under “Explore further” at the bottom of the page, click on “examples of microevolution” and read the examples provided.

4.  Summarize the 3 examples of microevolution on this page.

The Size of the Sparrow.
Coping with Global Warming
Building Resistance

--Go to the link “Artificial selection in the lab” and read about experiments with the evolution of guppies.

5. Summarize the results of the two different experiments (with and without predators).

When the guppies were in the present of the predators they would tend to blend in with their surrounding so they wouldn't be eaten. When there were no predators the male guppies would tend to stand out to attract the attention of females.

6. What types of selection were demonstrated in each experiment?  Are these experiments truly cases of artificial selection? Explain your answer.

The guppy selection in their surroundings!!! (questioning this)

PART 2: SEX AND THE SINGLE GUPPY

Go to http://www.pbs.org/wgbh/evolution/sex/guppy/index.html

Use the simulation to test different hypotheses about why some guppies are very brightly colored even though that makes them easy for predators to find.

1. Why do some guppies tend to be drabber than others?

It all depends on their surroundings because they adapt to it.

1. Why do some guppies tend to be more colorful?

The bright colors tend to attract females.

1. What role does color play in guppy survival?

The brighter the guppies are the more they will attract a predator and if they are dab they won't easily find a mate. Although the chances of them getting eaten are less.
4. Explain the push and pull that the environment (including predators) has on the coloration of guppies in Endler’s pools.
Its pretty much the same answer as number three.