Results from the Prince Creek Formation, which include some of the most detailed Arctic ecology reconstructions yet, were recently published. These discoveries illuminate the oldest relatives of our living salmon and carp. The findings, published in the journal Papers in Paleontology on May 7, mark a significant advancement in understanding the Arctic’s prehistoric ecosystem during the Late Cretaceous period.
At the same time, in this ‘land of plenty’, Arctic Alaska had become unaccustomedly harsh, with long months of wintertime darkness and biting cold. University of Alberta researchers, Lisa Van Loon and Neil Banerjee, relied on high-resolution synchrotron imaging technology to scan fossilized fish bones. Their research revealed extraordinary details about the evolution of these prehistoric creatures. Their work highlights a unique Arctic ecosystem, known as the Paanaqtat Province, where isolated evolutionary paths led to distinct aquatic life.
Harsh Conditions of the Late Cretaceous
During the Late Cretaceous, Arctic Alaska was a radically different place than it is today. The region suffered under a climate of perpetual winter — four months of continuous darkness per year and average annual temperatures around 6°C. Those extreme winters fostered a challenging habitat, one which could only be survived by organisms specially adapted to do so.
As you can probably tell, the Prince Creek Formation was a dream come true for paleontologists, providing sediments rich with fossils from this ancient landscape. Though an unforgiving paradise, at the time Earth was filled with life of all shapes and sizes that adapted to their extraordinary surroundings. The fossils spell out an ecosystem that was not just surviving, but thriving in this sweltering climate.
Fossil archeological digs in this region have unearthed a unique assemblage of fish fauna that existed around 73 million years ago. This interval preserved a unique underwater ecosystem, allowing scientists to study how organisms evolved to thrive in chillier, pitch-black environments.
Groundbreaking Discoveries in Fish Evolution
Among the most prominent discoveries are two new species of pike-like fish: Archaeosiilik gilmulli and Nunikuluk gracilis. These species are critical to the study of the evolutionary history of fishes widespread in northern waters. The researchers utilized synchrotron technology to virtually reconstruct fish in 3D, bone by bone, allowing for detailed analysis without damaging the fossils.
The research discovered Sivulliusalmo alaskensis, nicknamed the “first salmon of Alaska.” It’s now been determined by scientists that this species is the earliest known member of the salmon family. It beats the former record—set by the Jurassic period—by almost 10 million years! The find of Sivulliusalmo alaskensis highlights how important the Prince Creek Formation is in uncovering evolutionary timelines.
Moreover, the study featured evidence stemming from cypriniforms—the order that includes all the extant minnow and carp relatives. These fossils show how early fish were key in creating the aquatic ecosystems we see today. Their impact on these environments was truly dramatic and transformational.
The Unique Arctic Ecosystem
These discoveries from the Prince Creek Formation document a one-of-a-kind Arctic ecosystem. This community-inspired tech- and arts- ecosystem has come to be called the Paanaqtat Province. This rich but fragile ecosystem provided the natural barriers to let some animals evolve into distinct species without the influence of other ecosystems.
The possibility of finding completely new species just by capturing detailed scans emphasizes the need for continued research in the field of paleontology. Using these scans, Van Loon and her team were able to detect species that are already in existence. Their work unlocked new doors for figuring out long unknown relatives.
Together, researchers are working to reassemble ancient ecological puzzles. As they do, they receive high level insight from scientific experts into how climate and geography influenced life in the Arctic millions of years ago. These findings have wider implications for predicting evolutionary processes and biodiversity in novel ecosystems due to anthropogenic change.