Scientists have discovered a new species that lived more than 500 million years ago -- a form of ancient echinoderm that was ancestral to modern-day groups such as sea cucumbers, sea urchins, sea ...

Marine biologist Dr. Dave Pawson has embarked on over 100 dives to the ocean floor to unravel the mysteries of elusive invertebrates like sea cucumbers and brittle stars Emma Saaty There are few ...

THOUGH loth to prolong this discussion, I wish, in fairness to Dr. Mortensen and myself, to say that I did not accuse Dr. Mortensen of regarding the echinoderm metamorphosis as a case of metagenesis.

Echinoderms are a phylum of exclusively marine deuterostome invertebrates characterized by pentaradial symmetry in adults, a calcareous endoskeleton composed of ossicles, and a unique water vascular ...

This article was originally featured on The Conversation. After four years of digging for fossils in a churchyard in York, Pennsylvania, amateur paleontologist Chris Haefner made an intriguing find.