Study reveals new family tree for ray-finned fish

Aug 07, 2012 By Bill Hathaway
A genetic analysis by Yale researchers show that the earliest ray-finned fishes called teleosts are more ancient than thought and appeared almost 300 million years ago. However, the much more diverse and familiar species of teleosts arose at about the same time as birds and mammals — about 120 to 60 million years ago. (Illustration by Thomas Near, Alex Dornburg, and Ron Eytan)

(Phys.org) -- The most common lineages of fish found today in oceans, lakes, and rivers evolved about the same time as mammals and birds, a new Yale University-led study shows.

The comparative of more than 200 , reported the week of Aug. 6 in the , gave an earlier than expected evolutionary birthday to well-known teleost — or ray-finned — such as salmon, bass, or tuna.

The analysis also shows that the very earliest lineages of living teleost fish were eels and bonefishes, not tropical freshwater bonytongue fish as some scientists had proposed.

“Half of all animals that have backbones are ray-finned fish, but we know little about their evolutionary history in contrast to other vertebrate lineages like frogs, lizards, birds, and mammals,” said Thomas Near of the Department of Ecology and Evolutionary Biology at Yale and lead author of the paper. “Fish are usually viewed as primitive in origin, but we are learning that most of the familiar living lineages of fish arose more recently — during what we might call the Second Age of Fishes.”

The Devonian period, 415 to 355 million years ago, is known as the Age of Fishes and saw the appearance of many types of fish such as bony fishes, sharks, skates, and rays, as well  lineages known only from the fossil record. The living lineages of teleost fish — the major group of ray-finned fish — were thought to have appeared some 150 million years ago. The Yale study suggests the evolutionary age of living teleosts may be closer to 300 million years old.

However, the analysis shows the great majority of teleost found today appeared much later — in the Cretaceous through the Paleocene, some 120 to 60 million years ago, along with the first and . Near and his team are investigating whether the extinction event some 65 million years ago that killed off the last of the dinosaurs also may have facilitated teleost fishes to radiate throughout the world’s oceans and rivers, just as it led to rapid expansion of mammalian and bird diversity.

“The new family tree of ray-finned fish comes close to completing the book on the evolutionary relationships of vertebrates,” Near said.

Other Yale authors on the study are Ron I. Eytan, Alex Dornburg, and Kristen L. Kuhn.

The team of researchers included scientists from the University of California-Davis, John Wilkes Honors College, The Field Museum of Natural History, and the University of Oxford, United Kingdom.

Explore further: Rare new species of plant: Stachys caroliniana

Related Stories

Chinese report important fish fossil find

May 05, 2006

Chinese researchers say a newly discovered fish species that lived more than 400 million years ago may represent a bridge between two vertebrate lineages.

Recommended for you

Rare new species of plant: Stachys caroliniana

23 hours ago

The exclusive club of explorers who have discovered a rare new species of life isn't restricted to globetrotters traveling to remote locations like the Amazon rainforests, Madagascar or the woodlands of the ...

Mysterious glowworm found in Peruvian rainforest

Nov 21, 2014

(Phys.org) —Wildlife photographer Jeff Cremer has discovered what appears to be a new type of bioluminescent larvae. He told members of the press recently that he was walking near a camp in the Peruvian ...

The unknown crocodiles

Nov 21, 2014

Just a few years ago, crocodilians – crocodiles, alligators and their less-known relatives – were mostly thought of as slow, lazy, and outright stupid animals. You may have thought something like that ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

chardo137
not rated yet Aug 07, 2012
I thought that the origin of birds and mammals had already been pushed back further than this.
Torbjorn_Larsson_OM
not rated yet Aug 07, 2012
It is interesting how the oceans have been unfriendly with fish. All rayfin fishes (actinopyterygians) in the diagram derives from freshwater fish that likely reinvaded seas that for some reason were emptied on most fish. http://whyevoluti...cestors/ . And now see how they eked out a meager diversity before the major explosion.

@ chardo127: Definitely, I think they are describing modern birds (avian dinousarus) and mammals. Which reminds me, the first fossil evidence of tetrapods are now ~ 395 million years ago (unambiguous footprints in Poland), which is shortly after the Age of Fishes got started. Ironically, some fish did better on land than in water at the time.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.