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Don't call it a seagull!
[摘要] Many people assume there;;s only one kind of ;;seagull.;; On the contrary, the world is home to dozens of gull species spanning an array of shapes, sizes, plumage patterns, behaviors, and lifestyles (and some of those gulls aren;;t affiliated with the sea at all). The pattern of similarities and differences between species poses an interesting taxonomic challenge: Can we interpret that pattern to reconstruct evolutionary history and determine where each species fits on the gull family tree? Up through the twentieth century, our efforts to retrace evolution relied on comparisons of superficial traits-but as we discovered along the way, such traits can be misleading. In the past couple of decades we have developed a much more reliable window into the evolutionary past: rather than comparing outward characteristics, we have begun comparing genes. Modern taxonomy has taught us much about the gulls and helped us better understand the planet-wide ecological network that we all belong to.
[发布日期]  [发布机构] Massachusetts Institute of Technology
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