2) Myths and Misconceptions

 "Survival of the fittest"

Survival of the fittest is misconceived to mean that individuals who are stronger, better, and faster are the ones who are going to survive. If this were the case in evolution, we would expect to see more creatures that look muscular, like a lion or tiger.



(Royal Bengal Tiger)                             (Barbary Lion)              

How come we have things like this?


 
(Monarch Butterflies)           (Leaf Sheep Sea Slug)

This was a question that had plagued me until I learned about Evolutionary Fitness. 
Evolutionary fitness is how well an individual is suited to its environment. Fitness is also a measure of a population and how well they are able to survive and reproduce in their home environment. Suddenly the word "fitness" had a new meaning for me. 

There is a phrase that is often credited to Albert Einstein which states "Everyone is a genius. But if you judge a fish by its ability to climb a tree, it will live its whole life believing that it is stupid." This is what I now equate with fitness because it is true. If you take the sea slug and a tiger and swap their environments and diets, neither would survive. The tiger lives in a much drier environment and the sea slug needs to be in water to survive. Not to mention the sea slug is between 5 milimeters and 1 centimeter in length.* The factors that make one creature successful in their environment could be the very thing that kills them in another.




Looking at the illustration above, it is safe to say that color plays a factor in survival. In the Arctic, it snows rather heavily, so the Polar Bear has evolved to have white fur that blends into the snow. The Orangutan, however, is more well suited to the tropical environment as the characteristic orange fur does not blend in with the whites and greys in the Arctic. 

Some other features and characteristics allow both creatures to survive and reproduce in their home environments. The polar bear has thick, dense fur and lots of fat to help insulate against the cold, and its strong legs allow it to carry the bear long distances and swim through treacherous waters. The orangutan has long, powerful arms and hands that help deliver them from branch to branch in the highest trees in the Tropics. Opposable thumbs allow the orangutans to effectively break into fruit and grip tightly to surfaces. Their fur is long and sparse to help regulate their body temperature in warmer climates.

*Costasiella kuroshimae. (2024, August 21). In Wikipedia. https://en.wikipedia.org/wiki/Costasiella_kuroshimae 

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