A giant prehistoric salmon had tusk-like teeth on either side of its snout, a new study has found.
It is estimated to be up to 8.8 feet (2.7 meters) long. rainbow troutThe Pacific salmon is the largest salmon ever known, more than twice the size of the Chinook salmon, the largest Pacific salmon today.speckled trout), which Usually grows to about three feet (0.9 m) long.
Scientists have long been interested in Strongylostrongylus immitisextraordinary teeth, physical features reflected in the anatomy of fossil skulls. Initially, they thought the teeth were curved downward like those of saber-toothed cats, giving the species a common name: “saber-toothed salmon.”
However, a new study published Wednesday (April 24) in the journal PLOS One The teeth are shown to be more like warthog tusks, projecting sideways rather than downwards.
“[O. rastrosus had] These very unique features don’t exist anywhere else,” study first author Colin Clarksona professor of anatomy at the Philadelphia College of Osteopathic Medicine told LiveScience.
related: Will elephant tusks or rhino horns grow back?
First described in the 1970s, Strongylostrongylus immitis Swim in the waters of what is now the Pacific Northwest. A paper from 2016 Strongylostrongylus immitis According to reports, the fossils can be traced back to 12 to 5 million years ago.
Strongylostrongylus immitis A close relative of modern Pacific salmon, but not an ancestor, esp. sockeye salmonaccording to Clayson.
Like modern Chinook salmon, Clayson said, Strongylostrongylus immitis They may be born in freshwater rivers and streams but spend most of their time at sea, returning only to spawn (and possibly die).But unlike Chinook salmon, its diet consists primarily of composed of other fishThese ancient fish were filter feeders, feeding on plankton, sucking microorganisms into their mouths through their sieve-like gill rakers.
About 4.75 million years ago, Strongylostrongylus immitis According to Clayson, it is extinct.The first fossil is Collected in California and OregonBut they were disarticulated, meaning the teeth had become separated from the rest of the skull, Clayson said.Without a visual means of identifying the position of the teeth in the skull, the researchers knew that modern Pacific salmon have downward-facing teeth, so they inferred Strongylostrongylus immitis Did it too.
“It’s natural to assume that when you take this [tooth] Back in place, that’s what the future holds,” Clayson said.
In the 2010s, scientists discovered evidence that challenged this assumption.During a 2014 expedition to the Gateway Quarry in Jefferson County, Oregon, crews discovered more Strongylostrongylus immitis Clayson said the fossils include the skulls of a male and a female believed to be a breeding pair. Both skulls differ from earlier specimens in one key way: the mandibles are still connected, and the lateral orientation of the teeth is visually apparent.
When the skulls first came to Clayson’s attention, she was shocked by their appearance and thought it was a fluke. But then, she said, “they found more.”
CT (computed tomography) scans revealed specific features of the upper jaw, confirming that the teeth extend laterally away from the face – these results suggest initial sabertooth reconstruction Strongylostrongylus immitis Research shows that this approach is flawed.Based on this finding, the researchers concluded Strongylostrongylus immitis Should be renamed sharptooth salmon.
Despite its larger size, Strongylostrongylus immitis Clayson thinks this may be the target of modern carnivores. One would produce “a lot of meat,” she said.While the exact purpose of teeth is unclear, they may help Strongylostrongylus immitis Research shows they can ward off predators, compete with competitors and/or dig nests in streambeds. Clayson hopes to examine wear patterns on the teeth themselves to show their exact purpose.
#Giant #prehistoric #salmon #fanglike #teeth #warthog
Image Source : www.livescience.com