Mutation and the Tree of Life

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    DNA is a molecule containing genetic code and can be found inside the cells of every organism. This code contains pairs of bases and determines how an organism will develop and function. During replication, when the DNA is trying to elongate itself, mutations can occur. In the picture below, you can see an example of a mutation, where a base pair of TA turns into another CG pair. This specific type of mutation is called a transversion, but there are many other ways the genetic sequence can change. 

    Mutations can be large or small, and can even impact the survivability of an organism. To see an example of this we can look at the species Vulpes catticus. This species lives in an environment that frequently gets snow, so when a mutation occurs that results in the organism having white fur, it is beneficial to the organism's survival. As it can better blend in with its surroundings during the snowy months, it is more likely to survive to mating season, passing its genes along to future generations. In the second offspring, we can see that there is a mutation resulting in a second set of horns on its head. This mutation has no effect on the survivability of the organism, so it is neutral. However, looking at the last offspring we can see a mutation resulted in it having bright pink fur. This is an example of a harmful mutation, as this fur color stands out significantly against the snowy environment, meaning both predators and prey are more likely to see it. This mutation harms the organism's survival, so it and any offspring it passes the gene to are less likely to survive. 


Comments

  1. GeminiSeptember 8, 2024 at 8:56 PM

    Hello Rin, I appreciate your illustrations, they fit really will with your explanation on mutations, and what mutations could look like.

    ReplyDelete

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