The Big Issues

 Why are some clades very diverse and some unusually sparse? 

In evolution, many theories can often explain the same phenomenon. For this question, we are wondering why there is a lack of consistency in the level of diversity in modern-day insects. They are a great example since the Phylum Arthropoda has the greatest level of diversity in the Animal Kingdom. One important thing to understand is that evolution lacks any and all motivation and occurs completely at random. The first theory behind this is that the particular species of origin just happened to be in the right place and time for optimal conditions or adaptations to be presented and create a new species. Alternatively, that can occur at a different pace which is seen in mammals with their recent diversification in a short time. With the rapid diversification of species, there comes a lack of need for certain niches to be filled if multiple species are filling the same role. Ultimately, each of these theories explains various aspects of how diversity is inconsistent in today's organisms. 



Phylogenetic tree example

Comments

  1. Gracie FaverAugust 27, 2024 at 10:20 AM

    HI! I find it interesting that there are different theories to explain this phenomenon. I do think it is possible that a species is in the right place at the right time in order to flourish, but I find the second theory much more likely as it is not purely determined by chance or luck.

    ReplyDelete
  2. JodieAugust 27, 2024 at 12:05 PM

    Do you think the niche comes first or the diversification? - Dr. W

    ReplyDelete

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