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Rhizocarpon

  • enlarged photo
  • Image author: Danial Mosquin ©
  • Yellow map or world map lichen is frequently used in lichenometry, a geobotanical technique employed to estimate the age of exposure of a rock surface. Since Rhizocarpon geographicum quickly colonizes newly-exposed rock surfaces and has a known rate of growth, geologists can, for example, examine glacially-deposited rocks and determine the rate of glacial retreat. For an excellent introduction to lichenometry, read Lichens, Lichenometry and Global Warming, a short and well-illustrated paper by Richard Aston in the September 2004 issue of Microbiologist. 10/9/05
  • 10/3/05 Hope Slide, British Columbia, Canada
  • Original image
  • Website: Botany Photo of the Day
  • See also: Lichens, Lichenometry and Global Warming (PDF)