The most likely ancestors of the chordates are considered to be echinoderms because
A)tunicates are echinoderms.
B)there is a direct lineage from sea stars to tunicates.
C)embryos of echinoderms and chordate embryos are deuterostomes.
D)adult echinoderms display similar characteristics as adult chordates.
E)the nervous system of echinoderms is similar to that of chordates.

Question

Quizplus · Accepted Answer

Both echinoderm and chordate embryos are deuterostomes, meaning they exhibit similar patterns of early development. This suggests a common ancestry and supports the idea that echinoderms are the most likely ancestors of chordates. Tunicates, although part of the chordate phylum, are not believed to be direct ancestors of vertebrates. The similarities in nervous systems between echinoderms and chordates are not enough to definitively link them as ancestors.

The Most Likely Ancestors of the Chordates Are Considered to Be