Starfish cousin caught in the act of cloning himself

Washington: Some brittle stars give an arm and a leg to reproduce. When mates are scarce, these starfish-like marine creatures split in half. Each side then regrows the missing half, creating two identical clones of the original animal.

This process, known as clonal fragmentation, is practiced by nearly 50 species of extant brittle stars and their relatives, the starfish. However, scientists have found it difficult to determine when brittle stars, a gangly group of echinoderms, began reproducing in this way.

A fossil recently discovered in Germany pushes the origin of starfish cloning back to more than 150 million years. In an article published Wednesday in The proceedings of the Royal Society BA team of scientists describes the fossil of a fragile star that became petrified while regenerating three of its six limbs.

“It is the first fossil evidence of this phenomenon,” said Ben Thuy, a paleontologist at the National Museum of Natural History in Luxembourg and author of the new study. The specimen, he added, shows that “clonal fragmentation is actually much older than previously thought.”