Notebook

  1. Chemistry

    Movie viewers’ exhaled chemicals tell if scene is funny, scary

    Changes in trace gases exhaled by movie audiences could point the way to a subtle form of human communication.

    By Cassie Martin
  2. Plants

    Scary tomato appears to bleed

    A new species of Australian bush tomato bleeds when injured and turns bony in old age.

    By Sarah Schwartz
  3. Psychology

    Kids’ anxieties, depression need attention

    Psychological troubles in childhood are no longer considered a part of normal development.

    By Bruce Bower
  4. Climate

    U.S. weather has gotten more pleasant, but will soon worsen

    Warmer winters have made U.S. weather more pleasant since 1974 thanks to climate change, but that will soon change.