Blog Post Module 11: Reflection Prompt

How long does it take for new species to form? Do you think the speed of speciation varies among different modes of speciation? Look for evidence to support your conclusions!

I think it the length of time for a new species to form would vary for each species. It would also depend on how you define speciation. In the class textbook, there's at least 10 different definitions of what a species is in different contexts. I've been exposed to the Biological Species Concept (A species is a group of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups) the most, so I'd say I'm most familiar with this definition. 

I do think the speed of speciation varies among different modes of speciation (and by modes of speciation I think they're specifically referring to allopatric and sympatric speciation?) It's harder to tell if sympatric speciation has occurred compared to allopatric speciation because allopatric speciation has physical barriers while sympatric speciation has other not as apparent barriers between populations of species. In theory, this would make sympatry less common than allopatry. 

Although sympatric speciation may be more rare, I think it would be faster than allopatric speciation. According to a study on allopatric speciation and non-allopatric speciation rates within Drosophila, sympatric rates are about 2 to 5 times faster than allopatric rates. Even among these rates, variation is expected because species pairs may vary in particular evolutionary dynamics, population sizes, and genetic variability for reproductive isolation. 

THE RATE TEST OF SPECIATION: ESTIMATING THE LIKELIHOOD OF NON-ALLOPATRIC SPECIATION FROM REPRODUCTIVE ISOLATION RATES IN DROSOPHILA



 

Comments

  1. Kathryn14 November 2021 at 15:29

    I really enjoyed this blog post and I think the picture helped! Complex ideas like speciation require something to display what is being talked about, rather than just words. Great job!

    ReplyDelete

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