Evolution - BIOL 4133

Absolute Fitness vs. Relative Fitness Absolute Fitness  refers to how many offspring an organism has over it's lifetime.  Relative Fitness is the comparison of how many offspring and organism has over it's lifetime compared the most successful organism in the population regarding reproduction. Population Through Positive Selection: Two Evi's have different color patterns, the blue Evi blends into their environment better due to a recent change in sunlight, it is dark 90% of the time now. Due to the the blue camouflaging better Evi's have a better chance of survival, leaving them to reproduce the most off spring, this leaves the most beneficial alleles to be passed down (in this case the coding for a blue color). This process is called positive selection.

 Survival of the "Good Enough" vs Survival of the Fittest         Natural selection is depicted as survival of the fittest, however, this implies that only the fastest, strongest, and most superior reproductive systems will carry on their genes/survive. For example in this boxing match Mr. "Fittest" would always win, this is not the case in natural selection. The term "fittest" can be misleading and depict bad odds for the "good enough" organisms.      The "good enough" organism just has to be better than the organisms around them and survive long enough to reproduce. For example if a tiger were to chase after these organisms the good enough organisms just has to out run another organism or hide better than another organism. See picture below. Mr. "Good Enough" survived and survived many for occasion identical to this one and was able to reproduce and pass on his "good enough" genes.    

  Convergent Evolution:  This is when two or more types of species that are not of any close linage adapt similar phenotypes, genotypes, or even behaviors due to their environment.   Now let's dive into a specific example of convergent evolution from the book "Improbable Destinies." *Note: Explanation of convergent features are in the shapes.* How did this species adapt so similarly?  Both of the species have similar environmental pressures. Small creatures usually find a way to hid from big predators and due to their size in their environments, this could be why they both nest underground. Also due to their size working alone would not be feasible to they have both developed colonies of worker to survive.   

What is a mutation?   A mutation is a change in DNA (our genetic foundation) that can change how an organism looks or functions.  How could influence the evolutionary trajectory of this population of Evi's? Neutral Mutations: Color Change: This mutation does not significantly impact the Evi's fitness or survival. The change in DNA does not affect it's health or ability to reproduce. Over time the population could completely change color, which will have little to no affect or survival because they can blend in with their environment still.   Beneficial Mutations: Green Sickness Resistance : This mutation provided an advantage to the organism, improving its chances of survival because it is not facing death from this sickness and will continue to provide resistance for the population as it evolves.  Harmful Mutations: No Barrier : This mutation has a harmful impact on the Evi, reducing its ability to survive and reproduce due to the lack of protection. Over...