The concept of Natural Selection is actually much simpler
than it may initially appear. Thomas Huxley, Darwin's friend and "Bulldog" is said to have angrily proclaimed that he felt... . "extremely stupid not to have thought of that!" It's basic principles are all truly common sense:
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Evolutionary Pressure Selecting for Long Trunks in ElephantsAs always, the University of Berkeley's Understanding Evolution website does a great job explaining, as well as correcting common misconceptions about Natural Selection, such as organisms "wanting" to evolve, or evolving to get what they "need." |
Here is another simplified example illustrating the possible evolution of elephants with long-trunks from an ancestoral population of elephants with shorter trunks. Notice how the 4 Principles listed above apply to each of the 4 Steps seen here.
Step 1 - There is diversity/variation between elephants trunks Step 2 - Elephants with shorter trunks are not able to "compete" as well as elephants with longer trunks Step 3 - Longer trunk elephants are more evolutionarily "fit," meaning they are better adapted to their environment and better equipped to survive Step 4 - Long-trunk elephants have more kids who, in turn, also have long trunks |
ADDITIONAL RESOURCES
Glencoe McGraw-Hill "Visualizing Natural Selection" Video
Buggin' Out Camouflage Adaptation Game
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Darwin, Natural Selection, & "Who Wants to Live a Million Years?" Game