Breakthroughs and blind ends
نویسنده
چکیده
Evolution of a through gut with an oral and an anal opening conceivably marked a breakthrough in early animal history, as basal animals have a blind ending gut with only one opening. How this occurred, and whether a through gut evolved only once or several times is a matter of debate. Perhaps the different modes by which guts develop in animal embryos that are used for the classification of animals can shed some light on this question.
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عنوان ژورنال:
- Current Biology
دوره 19 شماره
صفحات -
تاریخ انتشار 2009