Image Gallery: A Worm Missing Link
Spartobranchus tenuis
Spartobranchus tenuis in a circular tube.
Worm Cluster
Clusters of Spartobranchus tenuis. Researchers analyzed more than 9,000 fossil specimens of the worms.
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Stephanie Pappas is a contributing writer for Live Science, covering topics ranging from geoscience to archaeology to the human brain and behavior. She was previously a senior writer for Live Science but is now a freelancer based in Denver, Colorado, and regularly contributes to Scientific American and The Monitor, the monthly magazine of the American Psychological Association. Stephanie received a bachelor's degree in psychology from the University of South Carolina and a graduate certificate in science communication from the University of California, Santa Cruz.