[揽瓜阁精读] 192.orchid

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192 orchid
P1: fossilised orchid pollen on a bee preserved in amber : 1st evidence orchid existed around time of the dinosaurs. HUB: fossilised orchid found in a now extinct bee means orchids much older than once thought, up to 80 million years old.
O: largest and most diverse plant family on earth, but been absent from the fossil record SR. Because 1.bloom infrequently 2, tend to live in tropical places where humidity and heat prevent fossilising.  R lucky to have a sample of orchid pollen
Amber first discovered in 2000. HM in 2005, dates back to 15-20million years old and carried pollinia orchids used to package pollen.
Researchers analysis DNA and estimated the age of O family about 80 million years ago.(age of common ancestor to all modern O) . orchid lived in the twilight（衰退期 黄昏）of dinosaurs. Late C
恐龙灭绝时orchids已经spread dramatically across the globe. Now Ois the largest plant with at least 25,000 species.
R: find resolve debate over age of O, also provide first direct evidence of ancient pollination. One of the first fossil observation both pollinator and the plant together.

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