Fossil Fish from the Late Cretaceous of Alberta

Dr. Don Brinkman, Curator Emeritus at the Royal Tyrrell Museum, discusses the challenges of trying to identify isolated elements of fossil fish, and the use of new technology that gives us further insight into the history of teleost fishes.
One of Dr. Brinkman’s long-term projects has been to try to understand the role of teleost fishes in Alberta’s freshwater communities during the Cretaceous Period. Teleosts are large ray-finned fishes that are well represented by fossils in the sediments laid down from ancient rivers flowing across Alberta.
It is rare to find articulated fish specimens (whole skeletons preserved as they were in life). Fishes are more commonly represented in the fossil record by isolated bones. Known as microfossils, they are often difficult to identify as belonging to specific groups.
Technology has made it possible to study fossil skeletons in new ways. Micro CT scanners allow very small fossils to be digitally examined. Using this technology, scientists have discovered that a fossil fish from 66 million years ago was an early member of the group that includes catfish, cyprinids, and suckers-one of the most important groups of living freshwater fish. The geographic distribution of isolated elements of this fish gives us new insights into the history of the group.