Notices
Results 1 to 5 of 5

Thread: genetic distance

  1. #1 genetic distance 
    WYSIWYG Moderator marnixR's Avatar
    Join Date
    Apr 2007
    Location
    Cardiff, Wales
    Posts
    5,810
    i read the following passage in a recent article in New Scientist :

    "The line that led to bonobos and chimps split from the one that led to Homo sapiens around 6 million years ago, and bonobos and chimps parted about 2.5 million years ago. However, genetic studies suggest we are slightly closer to bonobos than we are to chimps, ..."

    now this puzzles me : if bonobos and common chimps split from one another 3.5 million years after humans did, shouldn't the genetic distance between them and us be the same for both types of chimp ? or am i missing something ?


    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
    Reply With Quote  
     

  2.  
     

  3. #2  
    Forum Sophomore
    Join Date
    Jan 2007
    Posts
    158
    A couple of thoughts:
    -If one reproduces at a faster rate than the other, there are more opportunities for genetic variation to occur.

    -Changeable environment for one species could promote fast adaptation and a shift in the gene pool, perhaps increasing the frequency of certain new mutations where as a more constant environment for the other may make it less likely for certain new variations to spread.

    -I'm not sure what affects the likelihood of genetic mutation occurring, but it is possible that this could differ between the two.


    Reply With Quote  
     

  4. #3  
    WYSIWYG Moderator marnixR's Avatar
    Join Date
    Apr 2007
    Location
    Cardiff, Wales
    Posts
    5,810
    not sure if i agree with your link between adaptation and genetic variability, the main reason being that most of our DNA is junk DNA and does not get translated into enzymes and building body parts

    that's why imo molecular clocks can work : most of the DNA just records random mutation which swamps the small portion of DNA that gets expressed

    but i can see where you're coming from : e.g. the common chimp could have accumulated more changes to its genetic code since the days of the common ancestor

    is there anyone who can confirm that this is measured fact and not just wishful thinking just because we've started to perceive that bonobos seem to be more like humans in their social characteristics ?
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
    Reply With Quote  
     

  5. #4  
    Forum Sophomore
    Join Date
    Jan 2007
    Posts
    158
    Molecular clocks work on mitochondrial DNA don't they? I wouldn't mind knowing the methods of the studies and the amount of dna they tested, as this would no doubt affect the result.
    Reply With Quote  
     

  6. #5  
    WYSIWYG Moderator marnixR's Avatar
    Join Date
    Apr 2007
    Location
    Cardiff, Wales
    Posts
    5,810
    as far as i'm aware molecular clocks don't need to be restricted to mitochondrial DNA, it's just that for fairly recent events it's the most convenient one, since it's one of the faster ones
    "Reality is that which, when you stop believing in it, doesn't go away." (Philip K. Dick)
    Reply With Quote  
     

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
  •