Convergence, Natural Selection, 'Survival of the Fittest'

Convergent evolution is the independent evolution of unrelated species forming similar features or phenotypes. This can commonly be mistaken for divergent evolution, the process in which related species evolve different features or phenotypes, forming different species. An example of convergent evolution was discussed in chapter 1 of the book "Improbable Destinies", discussing the similarity in eyeballs between vertebrates and octopuses, an invertebrate. Their last common ancestor was roughly 550 million years ago, but their eyes are nearly identical! This convergent evolution occurred because both vertebrates and octopuses have the same genes to develop eyes from the common ancestor. Over time, after they split into different species, their environments caused an evolution of their phenotypes where individuals with good vision survive more than those with no vision. Because of this, both species developed the same phenotype for eyeballs, which look extremely similar because of the shared genes. 






Comments

  1. Kalissa MoseleySeptember 12, 2024 at 11:05 AM

    Wow! That is a really interesting example of convergent evolution! I didn't know that the genes were actually from a common ancestor causing the organisms to have the opportunity for the same phenotype. I would wonder what environmental pressures influenced the development of such a trait. Great job!

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  2. Keli P.September 13, 2024 at 9:14 AM

    Great job in explaining convergent evolution and how it differs from divergent evolution! I love how you used the phylogeny to show where the similar trait developed for vertebrates and octopi exemplifying that they developed separately.

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  3. AnnahSeptember 15, 2024 at 10:20 AM

    You did a great job of explaining convergent evolution! I also like how you explained how it differs from divergent evolution. The phylogeny tree is a great way to show how the trait was developed separately!

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