A ěcalcichordateî. The calcichordate hypothesis is ingenious but is not widely accepted. ěCalcichordatesî have echinoderm-like skeletons, and their ěchordate-likeî features are either ambiguous, or have homologies with perfectly good echinoderm features. Many are too young to be direct vertebrate ancestors. Some new fossil finds have strengthened the cephalochordate hypothesis. . . .
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