Did genetic adaptation help early African-Americans survive harsh conditions of slavery?

Did natural selection help African-Americans adapt to the harsh conditions of their new lives as slaves in the Americas? A team of researchers at the Chinese Academy of Sciences in Shanghai report in the journal Genome Research that "certain disease-causing variant genes became more common in African-Americans after their ancestors reached American shores — perhaps because they conferred greater, offsetting benefits." Read more at the New York Times.

Image: The Africans of the slave bark "Wildfire"--The slave deck of the bark "Wildfire," brought into Key West on April 30, 1860. Library of Congress.


    1. The moment that their genetic heritage is passed on after surviving the trip. (well as far as the research in the paper is concerned – as for the philosophical nature of your question that is a completely different question)

  1. I haven’t heard anything about this specifically but I do remember hearing a few years ago about someone drawing a link between high incidences of hypertension in African American males and the benefits of salt retention for victims of the Middle Passage – basically a large proportion of survivors of slave ships were individuals who retained salt and this led to their descendants being more likely to as well, etc.

    1. I read the same article….it was actually a couple of decades ago now.  I’d say late 1980s to early 1990s, if that helps jog your memory.

      The claim made in the article was that retention of salt meant you were less likely to die of dysentery.  Worth running the risk of hypertension 8 generations later.

        1. I wish we could actually see the full papers of both. 

          The Gravlee paper asserts that education and not genetic ancestry is a predictor of blood pressure in african americans. 

          The Jin paper identified areas of the genome that are different between a theoretical pre slave boat population (using existing african populations as a proxy) and post slave boat population (using modern, who knows what heavy selective pressures may have existed between landing and sampling, type people) and points out some of those genes are involved in hypertension. As the New york Times article points out there may be flaws. Also Dr Jin’s study apparently concludes that more genomes should be used in the comparison.

          The two actually do not conflict (based on abstract readings)

  2. Could wee just not go down this road? I hate to stifle scientific inquiry but I really don’t want myself or anyone else to read about how I come from well evolved slaves

  3. Did African-Americans genetically better adapted to the harsh conditions of slavery tend to have a higher chance to survive slavery? Obviously yes.

    The other way around is not just wrong but borderline racist.

    (If you wonder why: Your wording puts the origin of the genetic difference into their African genetic heritage, when the origin of said difference is in fact the inhumane selection process of slavery.)

  4. Golly, they all look so happy. And here I thought slavery was a bad thing…

    Thanks BoingBoings, my ancestoral guilt is gone. Must be because, as a white man, I’m genetically predisposed to self-forgiveness.

  5. Strange headline. The research concerns genes having to do with disease and would have far more to do with the transfer to America and interaction with European disease cultures than slavery itself. The findings in question also seem highly uncertain according to the article. Even then, the article says “certain disease-causing variant genes became more common /…/ perhaps because they conferred greater, offsetting benefits”. The only possible positive change mentioned is a gene combatting influenza coming from European heritage.
    Regardless, genetic adaptation would certainly *not* have helped the “early African-Americans” if some kind of population is concerned, since they would only change the population over time. Genetic variation or mutation might have helped certain individuals, as that’s pretty much how it works.
    Given the infected subject matter and multitude of myths and stereotypes, I would have expected a bit more prudence and a little less clickbaiting.

    1. “The findings in question also seem highly uncertain according to the article” That is because the actual research was a genome wide assessment of variation between a reconstructed pre stuff people in a boat and see who lives and a post hey they lived and had babies. The actual reasons for why certain gene variations were picked up is not studied. 

    2. Regardless, genetic adaptation would certainly *not* have helped the “early African-Americans”

      In fairness to Xeni’s headline, genetic adaptation was responsible for insuring the early African Americans had lungs capable of breathing the air on this planet, to name but one helpful adaptation.

  6. FYI Slave ships were not as comfortable as the above image…  they were more like this: http://ageofsail.files.wordpress.com/2009/03/slave-ship.jpg?w=500&h=395

      1.  Er, if you look closely… or even not so closely… at the image Chris Albon posted you will note the slave quarters have a maximum height of “two feet seven inches between the beams, and far less under the beams”.  Sitting up is barely possible; lying in chains mandatory.

        Keep in mind, though, that not all slavers used ships custom-built for the trade.  Some used whatever disease-ridden scow they could find, and there’s no doubt that there was always more room available at journey’s end than at the loading.

        1. Er, if you look closely … or even not so closely … at the image Xeni posted, you will note the slave quarters in the background.

        2. By 1860, IIRC almost all slave ships were purpose built. They were built for speed not for space, though, as they had to outrun the Preventive Squadrons the Royal Navy stationed off West Africa to stop them.

          1. On the other hand, the United States was not supposed to be importing slaves after 1808. So an 1860 slave ship was more likely to be supplying the Spanish Americas.

            The TransAtlantic Slave Trade Database shows that 5900 slaves were imported into North American ports between 1808 and 1860, a small fraction of the total trade during that period.

      2. From Howard Zinn’s A People’s History of the United States:

        The height, sometimes, between decks, was only eighteen inches; so that the unfortunate human beings could not turn around, or even on their sides, the elevation being less than the breadth of their shoulders; and here they are usually chained to the decks by the neck and legs. In such a place the sense of misery and suffocation is so great, that the Negroes… are driven to frenzy

        On one occasion, hearing a great noise from below decks where the blacks were chained together, the sailors opened the hatches and found the slaves in different stages of suffocation, many dead, some having killed others in desperate attempts to breathe. Slaves often jumped overboard to drown rather than continue their suffering. To one observer a slave-deck was “so covered with blood and mucus that it resembled a slaughter house”.

    1. Despite the caption, I don’t think that is the slave deck of the ship. Note the lines (ropes) and belaying pins on the rail in the background. The crew would need access to these to sail the ship, and it would be hard to do that while tripping over/stepping on slaves- especially since you might need to have several men hauling on a line.

      I have heard that slaves were forced to go up on deck periodically during the voyages as the fresh air and sunlight made survival more likely. This picture could be of one of those times.

      1. “Jimmy the Greek;” some odds maker, got fired from CBS sports for stating the above in a very vulgar, unintelligent way crediting slavery.  It can be seen at his wiki entry:

  7. I suspect this thread will not end well.  Sometimes I wonder if Xeni is here just to troll the readers.

    1. Troll tangent: Can Chinese researchers do this research because they do not have to worry about the impact of public pressure an equivalent researcher in the US would face for  doing the same research?

      1.   Further, are they doing it as Chinese researchers because it brings up one of the blackest periods in American history?

  8. Alternate reading: “Did vast numbers of slaves die of highly contagious diseases leaving the surviving slave population primarily consisting of those with natural immunities?”

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