Notices
Results 1 to 3 of 3

Thread: Why is it so surprising that convergent evolution may use the same genes in different species?

  1. #1 Why is it so surprising that convergent evolution may use the same genes in different species? 
    Forum Freshman
    Join Date
    Dec 2017
    Posts
    5
    Hey, so I'm writing a piece on the convergent and parallel evolution of genes involved in domestication but I'm a little confused.


    A lot of the literature talks about certain genes that are involved in domestication appearing 'more often than by chance' in orthologous (the same) genetic loci of multiple crops (i.e. trait A is controlled by gene A in crop 1. The same trait A has evolved convergently by a gene in crop 2 that is on the same part of the chromosome of crop 2 as gene A was on crop 1). Essentially, phenotypic convergence is controlled through genotypic convergence.


    However, I feel like I'm missing the significance of this point. Surely, it shouldn't be surprising that there has been parallel evolution occurring on the same genetic loci when these two species are related (e.g. cereal crops Sorghum and Maize share similar genes involved in domestication trait of 'seed size increase' and as a result the genes involved in this process are on similar loci for both crops)? This would make sense - one gene controls one trait in one crop why is it SO SURPRISING the same gene controls the same trait in another crop??


    Also another question: if this was true then why are other phenotypic traits in related species NOT controlled by the same genes (e.g. seed-shattering trait in cereal crops is controlled by different genes in different species of crop)?


    Reply With Quote  
     

  2.  
     

  3. #2  
    Forum Professor Zwolver's Avatar
    Join Date
    May 2006
    Location
    Netherlands
    Posts
    1,666
    Quote Originally Posted by Dean22April View Post
    Hey, so I'm writing a piece on the convergent and parallel evolution of genes involved in domestication but I'm a little confused.


    A lot of the literature talks about certain genes that are involved in domestication appearing 'more often than by chance' in orthologous (the same) genetic loci of multiple crops (i.e. trait A is controlled by gene A in crop 1. The same trait A has evolved convergently by a gene in crop 2 that is on the same part of the chromosome of crop 2 as gene A was on crop 1). Essentially, phenotypic convergence is controlled through genotypic convergence.


    However, I feel like I'm missing the significance of this point. Surely, it shouldn't be surprising that there has been parallel evolution occurring on the same genetic loci when these two species are related (e.g. cereal crops Sorghum and Maize share similar genes involved in domestication trait of 'seed size increase' and as a result the genes involved in this process are on similar loci for both crops)? This would make sense - one gene controls one trait in one crop why is it SO SURPRISING the same gene controls the same trait in another crop??


    Also another question: if this was true then why are other phenotypic traits in related species NOT controlled by the same genes (e.g. seed-shattering trait in cereal crops is controlled by different genes in different species of crop)?
    Actually this makes you kind of miss the mark. I usually explain things in metaphors, so hereby my metaphor for this situation.

    Imagine you Shoot at a target 3 times... First time, you hit bullseye. Second time, you miss, by a lot... but you hit bullseye on another target. Third time, you miss the target again, and hit the bullseye on another target. This is surprising. That by missing, you don't hit any random area in between, but the same type of bullseye in another target. It's not impossible, but surprising.

    In genetics, if something evolved separate. You expect separate solutions for similar problems. A problem a plant may have is drought. A solution may be to pack up on fatty substance to cover the leaves and stems. This fatty substance will be significantly different in each plant, as the variation of it is theoretically huge. So, take into account, this huge theoretical possibilities, and then finding out that all of the plants would have the exact same substance, of even a similar substance, would be surprising.

    That humans looking for the preferred traits by phenotype, would also have genotype similarities, would be not impossible though, but surprising none the less. Especially if in a high correlation.

    Buuuut.. When looking at familiarities.. If they share a common ancestor close enough, they may have genetic variation that are common in this group (and or junk DNA variation groups), having larger similarities of not used DNA, which can be activated in random, and then chosen because it increased the food production.

    Oooooor.. If they live in close proximity, you have the chance of interbreeding with some species. They could form a temporary hybrid species, which then gets bred back into either pure variation and itself would have gone extinct. This may have occured between several crops in our past.

    Oooooor.. Viral intervention, i use this in many explanations as an alternative option. As viruses could do this, putting a random piece of DNA inside another organism.

    But it is quite interesting. i will read into it a bit more.


    Growing up, i marveled at star-trek's science, and ignored the perfect society. Now, i try to ignore their science, and marvel at the society.

    Imagine, being able to create matter out of thin air, and not coming up with using drones for boarding hostile ships. Or using drones to defend your own ship. Heck, using drones to block energy attacks, counterattack or for surveillance. Unless, of course, they are nano-machines in your blood, which is a billion times more complex..
    Reply With Quote  
     

  4. #3  
    Forum Freshman
    Join Date
    Dec 2017
    Posts
    5
    Ah thanks so much for the reply that explains it well (metaphors definitely help!)
    Reply With Quote  
     

  5. #4  
    Forum Freshman
    Join Date
    May 2018
    Posts
    6
    I think that it is possible everything depends on the phenotype that you are determining
    Reply With Quote  
     

Similar Threads

  1. Replies: 20
    Last Post: May 31st, 2013, 07:46 PM
  2. Replies: 3
    Last Post: February 14th, 2013, 07:00 AM
  3. Convergent Evolution
    By Golkarian in forum Biology
    Replies: 5
    Last Post: September 6th, 2009, 12:02 AM
  4. The connection between species in evolution
    By Raymond K in forum Biology
    Replies: 12
    Last Post: April 14th, 2009, 01:31 AM
  5. Evolution of Species theory
    By alex_mtl in forum Biology
    Replies: 15
    Last Post: August 3rd, 2006, 09:18 AM
Bookmarks
Bookmarks
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •