Mutation and the Tree of Life

 Mutation and the Tree of Life

What is mutation and how does it affect the tree of life? 

A mutation is a change in the genetic code that can lead to a change in a species. Every creature, big and small, has a genetic code that determines how they will look and survive in their environment. These mutations can also cause sicknesses such as cancer, leukemia, and Alzheimer's disease. A mutation that can affect evolution has to be able to pass from a parent to their child.

Let's meet the Pacific Mouse (Pacificus rodentus)! These mice build homes on the sandy beaches of the island of Puuwai. They forage in the ocean for kelp to eat! 

They have light brown fur on the top halves of their bodies and a light blue belly.  These characteristics allow the mouse to blend into the sand and the ocean.  Let's explore some mutations in Pacificus rodentius!

Looking at the family tree on the right, you will see that the first generation (indicated by "1") are all wild-type mice.  These are the ones that are tan on the top and blue on the belly.

In generation "2" we see our first mutation! One of the mice has a green color instead of a blue color, this is the harmful mutation. Why is this harmful? Maybe the green color makes the mouse stand out from its natural environment making it easy prey, so they are not able to reproduce and pass down their green color.

In generation "3" we do not see the green color, however, we have another mutation! This mutation makes the belly of the mice white instead. If we glance ahead at the rest of the tree we can still see this mutation but it shows up as much as the wild type coloration. This is what is called a neutral mutation, it does not affect the survival of the creature!

In generation "4" we see our last type of mutation, beneficial. This mutation has caused the mice to be a darker blue on the top instead of tan! How is this a beneficial mutation? Well, it could help the mice blend into the water more, allowing them to find more food, thus increasing the survival of their children. Looking forward through generations 5-7 we see that the beneficial mutation has become more successful than the wild-type! 



Comments

  1. Maddie MeinerSeptember 10, 2024 at 4:21 PM

    Hello Brooke! I loved your drawings of the mice it is so helpful in explaining your mutation example. This really shows how quickly a mutation can negatively affect a population!

    ReplyDelete
  2. AsheSeptember 13, 2024 at 7:58 PM

    Your drawings are adorable and look fantastic. I enjoyed reading your perfectly formatted paper and it was easy to follow.

    ReplyDelete
  3. AngeliqueSeptember 19, 2024 at 5:45 PM

    You have done a phenomenal job at illustrating mutations using the Pacific mouse. Your detail of harmful, neutral, and beneficial mutations were clear, concise and easy for us to understand. Excellent job again!

    ReplyDelete

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