Fitness and Selection

How can an individual in a population's absolute fitness be different than their relative fitness? The absolute fitness focuses on the individual's fitness without paying mind to that of the population. This would be the number of offspring that individual produces within it's lifetime. Alternatively, the relative fitness analyzes the individuals fitness relative to that of the population, so this would be the individual compared proportionately to the populations "most fit" individual. In this example, lets compare the colors green and pink. Initially, the mate preference is green in the idividuals seen at the top. However, the preference changes to pink individuals meaning those are more likely to mate. In the next generation, the individuals that are pink are more abundant than that of green. The absolute fitness of green individuals would be 4 each, but the relative would consider the individuals produced from the second generation in pink. Thus the relative fitness would be 4/5=0.8.

Comments

  1. Vanesa MaciasSeptember 28, 2024 at 6:36 PM

    You did a great job describing fitness and natural selection! Even if the green individuals create the same amount of offspring the relative fitness decreases because the next generation would have less offspring.

    ReplyDelete
  2. AngelSeptember 29, 2024 at 11:18 PM

    Your descripition of absolute and relative fitness is very clear. I'm realizing I forgot to mention tha part about relative fitness of comparison to the "most fit" individual in that population. Also, great idea to show examples of the equation.

    ReplyDelete
  3. AsheOctober 6, 2024 at 4:02 PM

    Your drawing was way easier to understand than the one I created. 10/10 on the minimalistic, get-the-point-across images.

    ReplyDelete

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