Cambrian stalked echinoderms show unexpected plasticity of arm construction
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چکیده
منابع مشابه
Cambrian stalked echinoderms show unexpected plasticity of arm construction.
Feeding arms carrying coelomic extensions of the theca are thought to be unique to crinoids among stemmed echinoderms. However, a new two-armed echinoderm from the earliest Middle Cambrian of Spain displays a highly unexpected morphology. X-ray microtomographic analysis of its arms shows they are polyplated in their proximal part with a dorsal series of uniserial elements enclosing a large coel...
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Reconstructing the feeding mode of the latest common ancestor of deuterostomes is key to elucidating the early evolution of feeding in chordates and allied phyla; however, it is debated whether the ancestral deuterostome was a tentaculate feeder or a pharyngeal filter feeder. To address this, we evaluated the hydrodynamics of feeding in a group of fossil stem-group echinoderms (cinctans) using ...
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ژورنال
عنوان ژورنال: Proceedings of the Royal Society B: Biological Sciences
سال: 2011
ISSN: 0962-8452,1471-2954
DOI: 10.1098/rspb.2011.0777