Uncategorized

  1. Earth

    Trees have a tipping point

    Satellite data confirm that the amount of forest cover can shift suddenly in response to relatively small changes in fire frequency and rainfall.

    By Alexandra Witze
  2. Humans

    Stone Age paint shop unearthed

    The discovery of tools for making a substance possibly used in body decoration suggests humans could invent and plan by 100,000 years ago.

    By Bruce Bower
  3. Humans

    Columbus’ arrival linked to carbon dioxide drop

    The depopulation of the Americas due to introduced European diseases may have spurred Europe's Little Ice Age.

    By Devin Powell
  4. Health & Medicine

    Vaccine makes headway against trachoma

    An experimental immunization might someday aid public health efforts to counter a blinding disease.