Plated Cambrian Bilaterians Reveal the Earliest Stages of Echinoderm Evolution
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Plated Cambrian Bilaterians Reveal the Earliest Stages of Echinoderm Evolution
Echinoderms are unique in being pentaradiate, having diverged from the ancestral bilaterian body plan more radically than any other animal phylum. This transformation arises during ontogeny, as echinoderm larvae are initially bilateral, then pass through an asymmetric phase, before giving rise to the pentaradiate adult. Many fossil echinoderms are radial and a few are asymmetric, but until now ...
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ژورنال
عنوان ژورنال: PLoS ONE
سال: 2012
ISSN: 1932-6203
DOI: 10.1371/journal.pone.0038296