Understanding Evolution

Similarities and differences: understanding homology and analogy (High School level) :

How do analogies evolve?

Often, two species face a similar problem or challenge. Evolution may then shape both of them in similar ways — resulting in analogous structures. For example, imagine two flower species that are not closely related, but both happen to be pollinated by the same species of bird. A flower that gets pollinated produces many seeds and has a big advantage over flowers that don't get pollinated.

This bird pollinates all three flowers, but prefers the long red ones.

If the bird prefers long red flowers, the flowers' shapes and colors may evolve in ways that make them more attractive to the bird. The two flowers might end up looking the same, even though they started out looking quite different from one another. Click the button below to see how the two flowers evolve over time.

 

View this article online at:
http://evolution.berkeley.edu/evolibrary/article/similarity_hs_08

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