Uncategorized

  1. Math

    Recycling Topology

    It’s hard to miss the triangle of three bent arrows that signifies recycling. It appears in newspapers and magazines and on bottles, envelopes, cardboard cartons, and other containers. The recycling symbol. Alternative (incorrect?) rendering of the recycling symbol. Cliff Long made a Möbius band the basis of his wood carving “Bug on a Band.” Photo […]

    By Ivars Peterson
  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.