IN NATURE of December 8 there appears an article by my friend Dr. F. A. Bather entitled “Echinoderm Larvæ and their Bearing on Classification.” The article consists of a review of Dr. Mortensen's work ...

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 ...

The end-Paleozoic witnessed the most devastating mass extinction in Earth's history so far, killing the majority of species and profoundly shaping the evolutionary history of the survivors.

Sea stars and their relatives eat, breathe and scuttle around the seafloor with tiny tube feet. Now researchers have gotten their first-ever look at similar tentacle-like structures in an extinct ...

The recent Invertebrate Wars reminded me of spectacular, but often ignored, group of gastropods. The parasites! This is a group that I have totally geeked out on in the past. In my previous work I ...

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.