Fitness and Survival

 Fitness and Survival

An individual can have an absolute fitness higher than their relative fitness. This is because relative fitness compares the individual to the population's average and absolute fitness compares the individual to a perfect member. An individual who is different from the population could have a better chance of surviving and reproducing than an average member. 


The first generation of individuals below have just moved to a new location. Where they are from they have tan, sandy beaches with clear water and plenty of places to hide. The new location is a bit less sunny, the beaches are less pristine, and have stones and debris with darker murkier water. Both individuals are successful and can reproduce with the lighter coat continuing with more success. 


Over the next few generations, the darker offspring can go out during the not-so-sunny day allowing them to gather more resources to give them an edge. The darker water complements their darker coloration and they are thus not preyed upon as much as their lighter counterparts subsequently allowing them to produce more offspring. The darker coat is a trait that allows the darker mouse to survive furthering its genetic fitness, this is positive selection. Positive selection is defined as the tendency of beneficial mutations to increase as the population continues to reproduce. This also allows for adaptive evolution to occur and for the continuation of a species after environmental changes. 








Comments

  1. Abby DeckerOctober 2, 2024 at 10:59 AM

    I love your example it helps the reader understand the topic so well! Your drawing is really cute too. Good job keep up the good work!

    ReplyDelete
  2. Vanesa MaciasOctober 6, 2024 at 11:47 PM

    I love your explanations about fitness and survival. The example you gave about the different environments (beaches) allows for better visualization of adaptions needed for survival.

    ReplyDelete
  3. JodieOctober 8, 2024 at 1:34 PM

    Nice illustration! How does absolute and relative fitness link back with your concluding explanations of positive selection and adaptation? - Dr. W

    ReplyDelete

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