Remains of ancient marine life
This deep-sea creature is with long arms, bristling with teeth, and the only survivor of 180 million years of evolution
Melbourne: Let us introduce you to Ophiojura, a strange deep-sea animal discovered in 2011 by scientists from the French Museum of Natural History, trawling the top of an isolated seamount called Banc Durand, 500 meters below the waves and 200 kilometers east of New Caledonia in the southwest Pacific Ocean.
Ophiojura is a type of brittle stars, which are distant cousins of starfish, with snake-like arms radiating from their bodies, which live on the seabed all over the world.
The eight arms, each 10 centimeters long and armed with rows of hooks and thorns. And the teeth! A microscopic scan revealed spiky rows of razor-sharp teeth lining each jawbone, which we believe are used to trap and shred its prey.
According to a report in Proceedings of the Royal Society B, Ophiojura indeed represents a type of animal completely unique and not previously described. It is one of a kind – the last known species of an ancient lineage, such as the coelacanth or the tuatara.
The researchers compared DNA from a range of different marine species and concluded that Ophiojura was separated from its closest living brittle stars by around 180 million years of evolution. This means that their most recent common ancestor lived during the Triassic or early Jurassic period, when dinosaurs were just starting out.
Since then, Ophiojura’s ancestors have continued to evolve, ultimately leading to the present situation, in which he is the only known survivor of an evolutionary lineage dating back 180 million years.
Surprisingly, researchers have found small fossil bones that resemble our new species in Jurassic rocks (180 million years old) in northern France, which is further evidence of their ancient origin.
Scientists called animals like Ophiojura “living fossils,” but that’s not entirely correct. Living organisms do not stay frozen in time for millions of years without changing at all. The ancestors of Ophiojura would have continued to evolve, admittedly in a very subtle way, during the last 180 million years.
Perhaps a more accurate way to describe these evolutionary solitaries is to use the term “paleo-endemic” – representatives of a once-widespread branch of life that is now confined to a few small areas and possibly just one. solitary species.
Although our new species is native to the Southwest Pacific, seamounts exist all over the world and we are just beginning to explore those in other oceans.