Natural Selection (Taylor Bub)

Title: Natural Selection Activity

Principle(s) Investigated:

Natural Selection

Standards:

Materials:

- forks - tweezers - beans - cups -handout

- plates - timer -chopsticks - spoons

Procedure: Give a detailed explanation of the procedure and include diagrams if possible.

Demonstration 1 QUICKWRITE

1. Teacher will number students off to break them into groups of 4 or 5 students. Each student within their perspective groups will receive one tool. The beans are placed in the center of the group on a plate. As a group, Students will make predictions as to which tool they think will work best and worst and why. These predictions will be recorded in the quick-write (Link above ^^^).

2. The teacher then sets the timer for 30 seconds, and tells students "go!". The students then try to pick up as many beans as they can into their cups using only the tool that they received. At the end of the time, students will count the beans to see which tool worked best and worst and will record their information on the handout provided. The student with the least amount of beans in their cup at the end of 30 seconds then "dies off".

3. The beans are all replaced on the plate in the center. Students will then play another round with only those forks that survived. Students will record data from each round until there is only one "species" left. This species has survived!! :)

4. Students will then analyze and discuss their data and record their hypothesis in the quick write.

Student prior knowledge: Students should

- have a general understanding of evolution, in that, species will change and evolve over time

- understand that individuals in a population will have variations,

Explanation: Give a thorough explanation of the experiment or demonstration. Your explanation should be written to give your fellow teachers a solid understanding and include greater detail than what you might provide for your secondary students. Make certain to include equations whenever pertinent.

After students are introduced to the concept of natural selection they might participate in this experiment. During the experiment, the students different tools will represent birds with different beak shapes, similar to Charles Darwin's finches in the Galapagos Islands. Some forks will be much better suited, while others will be difficult to manage. The more successful tools are representative of the birds that would have a greater advantage in their environment. The students will then understand better how some tools could be better suited for other purposes.

Questions & Answers: Give three thought-provoking questions and provide detailed answers.

1. How would you describe the principles of natural selection?

- Traits must vary within the population

- These same traits must be inheritable

- Not all organisms that are born will survive

- Survival must be caused by differences in specific traits (i.e. organisms with a specific trait will survive while those without it will not)

2. Is natural selection the same this as survival of the fittest?

- No, Natural selection is the actual change in populations of organisms over time, whereas survival of the fittest is the mechanism in which natural selection happens. For example, Survival of the fittest might refer to an individual organism surviving in its environment and being successful in reproducing. Natural selection would show how that organisms species evolved over time, maybe becoming more colorful (peacock's plumes) or developing longer necks (giraffes).

3. Could natural selection work against the survival of an organism?

- Yes. Sometimes, traits that are more appealing for an organism to find a mate can cause an organism to be more susceptible to predators. For example, a male peacock with bright plumage might be able to attract many female peacocks, but that same bright plumage would also make him more easily seen by predators and therefore more likely to be eaten.

Applications to Everyday Life: Explain (don't just list) three instances where this principle can be used to explain other phenomenon.

1 - Antibiotics - We use antibiotics to fight bacterial infections in our bodies. However, some bacteria have developed mutations that make them resistant to antibiotics. So, when we contract a bacterial infection, and begin to take antibiotics to fight the bacteria, those with the resistance to it will survive and continue to reproduce, whereas the bacteria that do not have the mutation will die.

2 - Big Horn Sheep - In the wild, big horn sheep will fight over mating rights. They charge at one another at full speed and crash their horns into one another until one sheep either dies or submits to the other. The sheep that wins has earned mating rights with the female sheep. This has lead to big horned sheep having bigger and stronger horns over many generations.

3 - Pesticides - Many farmers use pesticides to kill off insects that might attack their crops. Some insects carry genes that make them resistant to these pesticides. Over time, the insects that are resistant to pesticides will survive and reproduce, while those insects that are not resistant to the pesticides will die off. Eventually, all the insects in these populations will be resistant to the pesticides and farmers will have to find a new variety to kill off the newer generation of pesticide resistant insects.

Photographs: Include photos and diagrams that illustrate the how the investigation is performed.

IMPORTANT NOTE:

DO NOT upload the photos to this site!!! If you do, they will be removed.

DO upload photos into the album linked in the left sidebar. Once you have uploaded a photo, click on the same album link, find your photo, right click on it, and "copy image address" (copy image URL) and then use this link when inserting the photo. The photo must be visible when viewing your page. A link to the photo does not suffice.

Videos: Include a video of your investigation

IMPORTANT NOTE: Embed a Youtube Video that illustrates the procedure and results. This video should reside in your YouTube account and should be viewable by all. You may use a video in another persons YouTube channel if the video is better quality than what you can make.

Video