Are humans getting dumber?

A provocative new study from a Stanford geneticist suggests it may be the sad truth

Topics: AlterNet, Stanford, Gerald Crabtree, PopSci, The Independent,

Are humans getting dumber?
This article originally appeared on AlterNet.

AlterNet A Stanford geneticist has published a provocative new take on evolutionary change: humans are actually getting dumber, at least when compared to ancient predecessors.

The geneticist, Gerald Crabtree, has published two journal articles on this hypothesis. According to the publication PopSci, Crabtree argues that “human intelligence may have actually peaked before our ancient predecessors ever left Africa…Genetic mutations during the past several millennia are causing a decline in overall human intellectual and emotional fitness…Evolutionary pressure no longer favors intellect, so the problem is getting exponentially worse.” Crabtree argues that this process, like other evolutionary processes, take a long time to emerge.

Crabtree’s central thesis to back his claim up is, according to PopSci , that “each generation produces deleterious mutations, so down the line of human history, our intelligence is ever more impaired compared to that of our predecessors.”

He argues that you can see evidence of this process in humans sense of smell. Now, humans are largely guided by intellect when it comes to what we eat, for example. Humans have “far fewer olfactory receptors than other animals,” according to Crabtree. Dogs, on the other hand, have more olfactory receptors (the neurons responsible for smelling things).

“Once you place pressure on intellectual abilities, and take it off of olfactory abilities, the olfactory genes deteriorate,” PopSci quotes Crabtree as saying.

You Might Also Like

But other geneticists have raised questions about Crabtree’s work. In an interview with The Independent , geneticist Steve Jones said that Crabtree’s paper was like “arts faculty science…Never mind the hypothesis, give me the data, and there aren’t any. I could just as well argue that mutations have reduced our aggression, our depression and our penis length, but no journal would publish that. Why do they publish this?”

Alex Kane is a staff reporter at Mondoweiss and the World editor at AlterNet. His work has also appeared in The Daily Beast, the Electronic Intifada, Extra! and Common Dreams. Follow him on Twitter @alexbkane.

More Related Stories

Featured Slide Shows

  • Share on Twitter
  • Share on Facebook
  • 1 of 11
  • Close
  • Fullscreen
  • Thumbnails
    jkrebs04, DesignCrowd.com

    Cities without landmarks

    Slide 1

    Niagara Falls, U.S./Canada

    akvarog, DesignCrowd.com

    Cities without landmarks

    Slide 2

    Sydney Opera House, Sydney, Australia

    iMAGICations, DesignCrowd.com

    Cities without landmarks

    Slide 3

    Mount Rushmore, South Dakota, U.S.

    jhgraphicsusa, DesignCrowd.com

    Cities without landmarks

    Slide 4

    Eiffel Tower, Paris, France

    Robert R., DesignCrowd.com

    Cities without landmarks

    Slide 5

    Colosseum, Rome, Italy

    Anythingoes, DesignCrowd.com

    Cities without landmarks

    Slide 6

    Taj Mahal, Agra, India

    Sergio Coelho, DesignCrowd.com

    Cities without landmarks

    Slide 7

    Siena Cathedral, Siena, Italy

    Anythingoes, DesignCrowd.com

    Cities without landmarks

    Slide 8

    Christ the Redeemer, Rio de Janeiro, Brazil

    iMAGICations,DesignCrowd.com

    Cities without landmarks

    Slide 9

    Arc de Triomphe, Paris, France

    iMAGICations, DesignCrowd.com

    Cities without landmarks

    Slide 10

    Lost City of Petra, Jordan

  • Recent Slide Shows

Comments

0 Comments

Comment Preview

Your name will appear as username ( settings | log out )

You may use these HTML tags and attributes: <a href=""> <b> <em> <strong> <i> <blockquote>