Spontaneous smiles occur during irregular sleep or drowsiness (Credit: Aflo/Naturepl.com)

Baby monkeys smile in their sleep

The smiles are just like those of newborn babies

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Earth Capture

(Credit: Simon Reed)
  1. (Credit: Simon Reed)
    Our otherworldly Earth
    1
  2. Zebra - in evening light on Kariega Game Reserve (Credit: Neil Aldridge)
    A wild portrait of South Africa
    2
  3. Giraffes by starlight (Credit: Mark Gee).
    Giraffes by Serengeti starlight
    3
  4. Catalina Island, Baja Sur, Mexico (Credit: Jack Dykinga)
    The wild beauty of Mexico
    4
  5. (credit: Tyler Sichelsk).
    16 spectacular shots of space
    5

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