How does evolution produce new and complex features?

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    When it comes to evolution, scientists still have many questions they are trying to find explanations for. Out of the 4 big questions, the one regarding how evolution produces new and complex features sounded the most interesting to me. 

    We can see examples of both complex and simple adaptions when we look closely at the biology of different creatures. For example, the eyespot of a Planaria is a simple organ in comparison to that of the multi-part human eye. The eyespots on Planaria are used to sense light and dark while human eyes provide complete true vision. 

    There are several ways that scientists theorize these complex adaptations evolve, and the two discussed in this article are advantageous intermediates and co-opting. The theory of advantageous intermediates states that there were intermediate stages that were subtly advantageous for an organism before leading to the fully-fledged complex adaption. Going back to the example of the eye, the light-sensitive eyespots of planaria were advantageous for its survival despite being 'half an eye'. 

    The second theory of co-opting states that these intermediate stages had a different purpose than that of the fully-fledged adaptation. While 'half a wing' is no good for flying, the feathers could have been used for insulation or for displaying to mates. "Natural selection is an excellent thief, taking features evolved in one context and using them for new functions" (evolution.berkeley.edu). 

Comments

  1. JodieAugust 27, 2024 at 11:52 AM

    Natural selection is, indeed, an excellent thief! - Dr. W

    ReplyDelete

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