Convergence, Natural Selection, 'Survival of the Fittest'

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     Convergent evolution is when two species that are unrelated evolve similar traits, structures, or features. However, these are analogous structures. This means that while they are similar in function, the structure is different and independently evolved in each species. This may lead one to believe that these species are closely related and share a common ancestor, but this is not always the case. There is also convergent evolution, which is different from divergent evolution as it is when multiple species with a common ancestor evolve homologous structures.  

    An example of evolution through convergence can be seen in whales. Before whales were recognized as mammals, people assumed they were a type of fish due to the similar structures of fins and flippers. We now know that these structures were due to convergent evolution. These shared structures most likely came about through natural selection and the shared selection pressure of being in an aquatic environment. Whales are more closely related to land mammals than to fish, which can be seen when looking at their bone structures, meaning that these structures similar to that of fish evolved separately to fill their own ecological niches. 



Comments

  1. Desseray CardonaSeptember 15, 2024 at 11:57 PM

    Wow, amazing drawings! Your explanation is clear and easy to understand.

    ReplyDelete
  2. JodieSeptember 20, 2024 at 12:59 PM

    Beautiful illustration of homology!

    ReplyDelete

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