New coelacanth find rewrites history of the ancient fishMay 03, 2012
(Edmonton) Coelacanths, an ancient group of fishes once thought to be long extinct, made headlines in 1938 when one of their modern relatives was caught off the coast of South Africa. Now coelacanths are making another splash and University of Alberta researchers are responsible.
Lead U of A researcher Andrew Wendruff identified fossils of a coelacanth that he says are so dramatically different from previous finds, they shatter the theory that coelacanths were evolutionarily stagnant in that their body shape and life-style changed little since the origin of the group.
Wendruff says his one-metre-long, forked tailed coelacanth was an 'off-shoot' lineage that lived 240 million years ago. It falls between the earliest coelacanth fossils of 410 million years ago and the latest fossils dated about 75 million years ago, near the end of the age of dinosaurs.
"Our coelacanth had a forked tail, indicating it was a fast-moving, aggressive predator, which is very different from the shape and movement of all other coelacanths in the fossil record," said Wendruff.
Wendruff's research co-author, U of A Professor Emeritus Mark Wilson, describes typical coelacanths as having chunky bodies, fins of varying size and broad, flexible tails. "These fish were slow moving and probably lay in wait for their prey," said Wilson.
Wendruff's coelacanth is named Rebellatrix, which means rebel coelacanth. The researchers say Rebellatrix came along after the end-Permian mass extinction 250 million years ago, an event so lethal it wiped out 90 per cent of marine life. Rebellatrix filled a previously unoccupied predator niche, but it didn't fare well.
"Rebellatrix was likely a spectacular failure in the evolution of cruising predation," said Wendruff. "Clearly some other fish groups with forked-tails must have outperformed this coelacanth as it does not appear later in the fossil record."
The fossils of Rebellatrix described by the U of A team were found in the Rocky Mountains near Tumbler Ridge, British Columbia.
The research by Wendruff and Wilson was published May 2, as the cover article in the Journal of Vertebrate Paleontology.
University of Alberta
Related Coelacanth Current Events and Coelacanth News Articles
First shark genome decoded
An international team of researchers, including scientists of the Max Planck Institute of Immunobiology and Epigenetics, has sequenced and analyzed the genome of the elephant shark.
From obscurity to dominance: Tracking the rapid evolutionary rise of ray-finned fish
Mass extinctions, like lotteries, result in a multitude of losers and a few lucky winners.
Diversification in ancient tadpole shrimps challenges the term 'living fossil'
The term 'living fossil' has a controversial history. For decades, scientists have argued about its usefulness as it appears to suggest that some organisms have stopped evolving.
Scientists discover the most primitive living eel
Scientists at the Smithsonian and partnering organizations have discovered a remarkably primitive eel in a fringing reef off the coast of the Republic of Palau.
Primordial fish had rudimentary fingers
Tetrapods, the first four-legged land animals, are regarded as the first organisms that had fingers and toes. Now researchers at Uppsala University can show that this is wrong. Using medical x-rays, they found rudiments of fingers in the fins in fossil Panderichthys, the "transitional animal," which indicates that rudimentary fingers developed considerably earlier than was previously thought.
Ancient antibody molecule offers clues to how humans evolved allergies
Scientists funded by the Biotechnology and Biological Sciences Research Council (BBSRC) have discovered how evolution may have lumbered humans with allergy problems.
Coelacanth fossil sheds light on fin-to-limb evolution
A 400 million-year-old fossil of a coelacanth fin, the first finding of its kind, fills a shrinking evolutionary gap between fins and limbs.
Mobile DNA part of evolution's toolbox
The repeated copying of a small segment of DNA in the genome of a primeval fish may have been crucial to the transition of ancient animals from sea to land, or to later key evolutionary changes in land vertebrates.
Living fossil roams the seas
Fossil' fish coelacanth, first dragged up along the coast of South Africa in 1938, having been considered extinct for 65 million years. Because of its close resemblance to land animals, it has attracted attention to the subject of a 'missing link' between tetrapods and humans.
Swedish-Chinese research team uncovers the history of the nose
Our ancestors had two nostrils, one front and one back, but no opening on the palate or in the throat. They could smell, but not breathe with their nose. How did our nose evolve? Per Ahlberg, Uppsala university, and Zhu Min, department of Vertebrate Paleontology in Beijing, China, has now found a fossil that explains the history of the nose.
More Coelacanth Current Events and Coelacanth News Articles