Beacon Transcript – An ancient fish may change the face of evolution as research led scientists to believe that it may be one of the ancestors of our jaws.
A study undertaken by a set of scientists including co-author Per Ahlberg, Sweden’s University of Uppsala’s paleontologist and published in the U.S. Science journal, considers that these strange ancient fish might be our jaws’ ancestors.
One such ancient fish specimen was discovered in China, in 2013, and is thought to be about 419 million years old. The armored swimmer sports a tank-like body coupled with a head not unlike a dolphin’s. The animal species is also called placoderm. What makes this specimen even more unique is its jaws.
As humans share three major jaw set bones with almost every other species of dogs, salmons, lizards, or other vertebrates, scientists have long since searching for the common ancestor.
The three major jaw bones common throughout the species are the premaxilla and maxilla of the upper jaw, and the dentary system of the lower jaw, and were discovered as early as the placoderms, though they presented an odd form.
The placoderms, which are thought to have swum in our Earth’s waters over hundred of millions of years ago, and which are older with some other hundred millions of years than even dinosaurs, have always sparked questions.
These ancient fish were demonstrated to have been the earliest animal species to present jaws, but theirs was an odd one as it resembled sheet metal cutters more than they did a modern jaw.
Their jaws sported bony blades that sliced together when cutting something, and are called gnathal plates. Before the current discoveries and due to their bizarre aspect, most researchers thought the armored fish to have been just a stranger branch of the vertebrate class.
The placoderms still pose a lot of questions to scientists, as no one is quite sure where to place them, and before their fossils’ discovery, mostly no one could have predicted the existence of such a species.
The same Ahlberg considers that the 419 million years old fossil along with the more recently discovered but just as old, Qilinyu rostrate, may show the origin of the current jaws as they form the perfect link between placoderms’ and our human and vertebrate ones.
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