As dinosaurs died, new species of fish filled the ocean
OREANDA-NEWS As dinosaurs and huge ocean predators disappeared 66 million years ago in a mass extinction event, lineages that comprise the bulk of marine fish species diversity began evolving and filled the seas, a new, multi-institution analysis shows.
The findings by researchers from Yale, the University of California-Los Angeles, Louisiana State University, and the University of Michigan were published March 12 in the journal Nature Ecology and Evolution.
About 18,000 species of spiny-rayed fishes exist today, a diverse group that includes basses, tunas, deep sea anglerfishes, pufferfishes, and seahorses, and that comprises more than 25% of all living vertebrate species.
The research team analyzed more than 1,000 genes in living fish species and the spiny-rayed fish fossil record in order to estimate the timing of the evolutionary origin of the lineages that account for most of the species diversity of modern marine fishes. They found the evolutionary origin of these species’ lineages occurred at what scientists called Cretaceous and Paleogene boundary 66 million years ago.
“These lineages diversified just as dinosaurs were going extinct and placental mammals on land were emerging,” said Thomas Near, professor ecology and evolutionary biology, the Bingham Oceanographic Curator at the Peabody Museum of Natural History, head of Saybrook College, and senior author of the study.