Trends in Evolution

 The question that interested me the most from the reading in "The Big Issues" was "are there trends in evolution, and if so, what processes generate them?"

A trend in evolution occurs whenever there is a continuous development, not a random fluctuation, in the genotypic or phenotypic characteristics in a species. There are many different types of trends, such as an increase in the organism's speed or a decrease in body size, that can be seen throughout evolution. However, the processes that generate these trends is not always known. For example, the trends can begin in a species because they cause greater attraction by the opposite sex, increase survival rates, or aid in food consumption, but most of the time the trend can cause multiple benefits to the organism, so the main cause to begin this change is unknown. 

An example of this is seen in the image below. The trend is that researchers discover that this species of bird begins to lose its color over time. The process that generates this trend could be to increase survival rate because it is easier to blend into the environment or because females tend to select lighter colored males, increasing their reproductive chances. 




Comments

  1. JodieAugust 26, 2024 at 12:55 PM

    It's like evolution is complex! ;) - Dr. W

    ReplyDelete
  2. Allie DAugust 28, 2024 at 9:13 AM

    I have also found trends in evolution to be mind stimulating, the shifting of feather color is a great representation of trends! I personally favor amphibians and avions when discussing trends as both have such a great varieties that have been tracked and documented over time. Plus with ecological changes over time these two classes are affected greatly and we can see evolution in progress as these species try to avoid extinction.

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