News

  1. Earth

    Last Gasp: Toxic gas could explain great extinction

    Sudden venting of hydrogen sulfide from the deep sea could have caused the largest extinction in Earth's history by poisoning land animals and destroying atmospheric ozone that protects Earth from ultraviolet light.

    By Naila Moreira
  2. Anthropology

    Founding Families: New World was settled by small tribe

    A new genetic analysis indicates that only about 200 to 300 people crossed the ice age land bridge from Asia to become the founding population of North America.

    By Bruce Bower
  3. Ecosystems

    Pesticide makes bees bumble

    The pesticide spinosad, previously thought safe for bees, may damage their ability to forage for nectar.

    By Naila Moreira
  4. Tech

    Morphing wheels for beginner bikers

    A new bike design for kids morphs from tricycle into bicycle as the rider gets moving, possibly easing the often-fearful starts at riding two-wheelers.