18”h x 24”w framed 23”h x 29”w x 1.5”d

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One of the pleasures of hiking in the mountains is seeing the myriad of colors and patterns mosses and lichens make on the talus slope rocks. A particularly striking species of crustose lichen is the bright yellow Rhizocarpon Geographica, or Map Lichen, which grows on exposed rock in areas of relatively clean air. Its slow but constant rate of growth enables a scientist to calculate the time of the rocks exposure to the elements.

Map Lichens survive in the most extreme of conditions. So extreme that a specimen taken into space and exposed to 10 days of adverse temperatures and space radiation showed no detectable effects. They are in fact by far the oldest living organisms on the planet. Specimen in the arctic have been dated as old as 8600 years.

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