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Published byKatrina O’Brien’ Modified over 8 years ago
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Peppered moth Moth comes in two “versions”:
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Pre-Industrial Revolution Pre-industrial England was known for rolling hills, dense green forest, and picturesque valleys. Farming was the primary part of the economy for much of the country.
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Pre-Industrial Revolution The white peppered moth very common Blended in well (camouflage!!!) Lichens, tree branches, rocks
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Can you locate the Peppered Moth?
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Predators Birds ate the moth (which moth did they see?) Any moth that did not blend in very well was prone to get eaten
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Industrial Revolution Great deal of smoke and soot released into atmosphere
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No more camouflage Soot settled on rocks, trees Became darker Killed lichens Peppered moth lacking hiding places
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Melanism The black version of the peppered moth (previously very, very rare) now had significant advantage
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Natural Selection in action! No humans are selecting for black moths or white moths. Nature Nature is selecting against one or the other!
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Results The white-and-black moth went from the majority to the minority Estimated 99.9% to 2% Black moth went from 0.1% to 98% All of this in about a 40 year span VERY fast on a biological timescale!
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Recently The US and Europe now have cleaner air standards What happened to the proportion of peppered vs. black moths? Now shifted towards light-colored peppered moths again
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(Addendum) The peppered moth story is NOT the only piece of evidence for evolution Many, many other lines of evidence exist The peppered moth is NOT the strongest piece of evidence for evolution Just one of the most visually striking
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