September 20, 2012
AND IT'S MAGIC TIME IN NEW ENGLAND:
The Glory of Leaves : Sometimes a masterwork hangs in a museum. Other times it hangs from the branch of a tree or rounds out a slender stem. (Rob Dunn, October 2012, National Geographic)
We have all held leaves, driven miles to see their fall colors, eaten them, raked them, sought their shade. Since they are everywhere, it's easy to take them for granted.But even when we do, they continue in their one occupation: turning light into life. When rays of sunlight strike green leaves, wavelengths in the green spectrum bounce back toward our eyes. The rest--the reds, blues, indigos, and violets--are trapped. A leaf is filled with chambers illuminated by gathered light. In these glowing rooms photons bump around, and the leaf captures their energy, turning it into the sugar from which plants, animals, and civilizations are built.Chloroplasts, fed by sun, water, carbon dioxide, and nutrients, do the leaf's work. They evolved about 1.6 billion years ago when one cell, incapable of using the sun's energy, engulfed another cell--a cyanobacterium--that could. That cyanobacterium became the ancestor of every living chloroplast. Without their chloroplasts plants would be left like the rest of us, to eat what they find. Instead they hold out their green palms and catch light. If there is magic in the world, surely this is it: the descendants of tiny creatures in leaves, capable of ingesting the sun.
Posted by Orrin Judd at September 20, 2012 4:53 AM
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