The Big Issues - Why are some clades very diverse and some unusually sparse?

 The Big Issues - Why are some clades very diverse and some unusually sparse?

Clade is a term used to describe a group of organisms that evolved from a shared ancestor, such as the human and gorilla species.

Clades are potentially created by a myriad of factors, most notably of which being the following:

1.  Opportunity knockouts which could be due to limited reproduction due to limited wildlife mobility, environmentally-favored specialization adaptation, and/or niche population expansion due to lack of environmental species competition


2. Adaptive radiation: the ability of a single species to quickly diversify into many new forms. Note that human evolution is not considered to be an adaptive radiation process, because our evolution was not a quick process but rather a slowed, timely process. A good example of this ability are the Hawaiian honeycreepers who colonized the Hawaiian Islands and evolved into approximately 50 subspecies due to a lack of environmental species competition (an opportunity knockout). 



3. Changes in diversity throughout history: a couple pertinent examples of events that prompted species diversification are explosion and extinction. The Cambrian explosion occurred approximately 530 million years ago during the Cambrian period. This explosion of complex life is what is thought to have prompted the occurrence of marine clades! Extinction, which occurred approximately 225 million years, led to the eradication of approximately 90% of the species on Earth during that time period. With a great reduction in population, it is theorized clades were created due to a culmination of the aforementioned causes which could lead to mass diversification. 



Thank you for reading!

Comments

  1. JodieAugust 26, 2024 at 2:52 PM

    How visually stunning! - Dr. W

    ReplyDelete
  2. GeminiSeptember 1, 2024 at 10:03 PM

    Hello Angelique,

    Your take on clade diversity is really informative. Thank you for shedding light on this complex process! I really like your focus on the Hawaiian Honey Creepers beak evolution, it's really clear and super easy to follow.

    ReplyDelete

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