News

  1. Earth

    Traces of lead cause outsize harm

    Minute amounts of lead in blood are worse for children than had been realized.

    By Ben Harder
  2. Paleontology

    Ancestors Go South

    A group of new and previously excavated fossils in South Africa represents 4-million-year-old members of the human evolutionary family, according to an analysis of the sediment that covered the finds.

    By Bruce Bower
  3. Animals

    Chicks open wide, ultraviolet mouths

    The first analysis of what the mouths of begging birds look like in the ultraviolet spectrum reveals a dramatic display that birds can see but people can't.

    By Susan Milius
  4. Animals

    Fishy Paternity Defense: Bluegill dads: Not mine? Why bother?

    Bluegill sunfish have provided an unusually tidy test of the much-discussed prediction that animal dads' diligence in child care depends on how certain they are that the offspring really are their own.