3-D scans of fossils suggest new fish family tree
Analysis of specimens from China implies ray-finned fishes are younger than previously thought
![Polypterus](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2017/09/093017_notebok_rethink_main.jpg?fit=860%2C460&ssl=1)
PRIMITIVE FISH Polypterus (shown) is a living member of a large group of vertebrates called ray-finned fishes. New evidence suggests that ray-finned fishes arose about 360 million years ago, after a major extinction event, then their diversity exploded.
Matt Friedman/Univ. of Michigan