The Unz Review: An Alternative Media Selection
A Collection of Interesting, Important, and Controversial Perspectives Largely Excluded from the American Mainstream Media
 TeasersGene Expression Blog
No One Knows About the Third Human Admixture Into Melanesians
🔊 Listen RSS
Email This Page to Someone

 Remember My Information



=>

Bookmark Toggle AllToCAdd to LibraryRemove from Library • BShow CommentNext New CommentNext New ReplyRead More
ReplyAgree/Disagree/Etc. More... This Commenter This Thread Hide Thread Display All Comments
AgreeDisagreeLOLTroll
These buttons register your public Agreement, Disagreement, Troll, or LOL with the selected comment. They are ONLY available to recent, frequent commenters who have saved their Name+Email using the 'Remember My Information' checkbox, and may also ONLY be used once per hour.
Ignore Commenter Follow Commenter
Search Text Case Sensitive  Exact Words  Include Comments
List of Bookmarks

Vanuatu_blondeThere are several reports in the media about a third hominin group besides Denisovans and Neanderthals, and how they contributed to Melanesians. Science News has a sober summary of it all.

Several people have asked me on email and Twitter about this, and I told them to ignore it. The reason I say this is that I was in the room when the presentation was given, and it was clear people were having a hard time following what was going on. Afterward several pretty intelligent statistical human geneticists expressed great confusion.

A few things to take away. First, it was a presentation at a conference. One can’t expect very novel findings to be understood easily in a 15-30 minute talk. Wait for the preprint at least. Second, this was a presentation at a conference. A lot of presentations don’t pan out. If it’s a really surprising theoretical or interpretative finding, as opposed to sequencing a new species (an empirical result), generally I don’t pay close attention. A lot of time the reason that no one else has stumbled onto the surprising results is that they are wrong, or trivial upon further inspection.

Finally, there are complexities of human history we don’t have a good grasp on. There may indeed be other hominins which contributed to the human gene pool to the point of detectable admixture. I think it is likely. But it is a different thing to have specified all the details.

Basically, I wish the press would set a higher bar for presenting on new results from conferences. It’s not even that it’s not been peer reviewed. Often the results are provisional, and they don’t end up turning into the paper that’s promised.

 
• Category: Science • Tags: Genomics 
Hide 6 CommentsLeave a Comment
Commenters to Ignore...to FollowEndorsed Only
Trim Comments?
  1. Science reporting in general. Non-scientists who don’t understand science reporting on science to a public that largely doesn’t care about science with a minority who wants to be perceived as caring about science. What could go wrong?

  2. Thanks for this post. Was wondering about this exact topic today.

  3. I confess that I would be really surprised if it turns out that ‘modern humans’ had mixed with just three types of pre-modern humans. I also find it unlikely that there was a single Denisova ‘species’ that stretched from the Altai all the way to SE Asia. Especially considering that just in western Eurasia there were two separate species.

    • Replies: @Megalophias
    IIIRC the original Denisovan paper found that the Denisovan ancestors of Melanesians were not closely related to the Altai Denisovans; in fact the former were estimated to have diverged from the latter 276-403 thousand years ago.

    I haven't seen any figures for other Denisovan-admixed populations. In any case even if not separate species there was probably a great deal of structure. And this is only considering Denisovans, who are related to Neanderthals and MHs; late Homo erectus ought to be much more divergent.
  4. @terryt
    I confess that I would be really surprised if it turns out that 'modern humans' had mixed with just three types of pre-modern humans. I also find it unlikely that there was a single Denisova 'species' that stretched from the Altai all the way to SE Asia. Especially considering that just in western Eurasia there were two separate species.

    IIIRC the original Denisovan paper found that the Denisovan ancestors of Melanesians were not closely related to the Altai Denisovans; in fact the former were estimated to have diverged from the latter 276-403 thousand years ago.

    I haven’t seen any figures for other Denisovan-admixed populations. In any case even if not separate species there was probably a great deal of structure. And this is only considering Denisovans, who are related to Neanderthals and MHs; late Homo erectus ought to be much more divergent.

    • Replies: @ohwilleke
    Fascinating. I don't recall noticing that when the papers first came out.
  5. @Megalophias
    IIIRC the original Denisovan paper found that the Denisovan ancestors of Melanesians were not closely related to the Altai Denisovans; in fact the former were estimated to have diverged from the latter 276-403 thousand years ago.

    I haven't seen any figures for other Denisovan-admixed populations. In any case even if not separate species there was probably a great deal of structure. And this is only considering Denisovans, who are related to Neanderthals and MHs; late Homo erectus ought to be much more divergent.

    Fascinating. I don’t recall noticing that when the papers first came out.

  6. In any case even if not separate species there was probably a great deal of structure.

    That’s what I was thinking. If there were southern Denisovans with tropical immunities a branch who moved north might have lost them.

Comments are closed.

Subscribe to All Razib Khan Comments via RSS