Scientists have found that a kind of exotic micro-animal from the "lobopodians" is the first known example of what researchers call evolutionary regression, in which this creature got rid of its hind limbs for a simpler and more primitive physical form.
The researchers mentioned in the journal "Carnet Biology" that this animal called "the worm" (facivermis) was a species similar to the long and thin worms, and it had five arms in the upper part of the body, and the lower half of it was without limbs and it has a bulging background that helps it to cling to the Seabed.
Newsweek magazine pointed out that this type of organism inhabited Earth about 518 million years ago, during the Cambrian era, the first of the six eras of the era of ancient life and apparent life, when it was filtering food particles in water, and scientists have been baffling since its discovery thirty years ago.
And now only the scientists have come to the place of classification of this strange creature thanks to the well-preserved fossils collected from the sediments of the city of Xinjiang Utah in Yunnan province, southwest China.
Analysis of these fossils places the torchworm within the group of Cambrian foot lobes that preceded three modern animal groups, including arthropods such as insects, crustaceans and spiders, and slow-walking creatures such as aquatic bears, claw carriers or velvet worms.
The Flame Worm is the oldest known example of a phenomenon called "secondary loss", as it lost its legs in a manner similar to modern-day snakes.
The researchers pointed out that the way these organisms evolve contradicts what they expect, since in most cases organisms evolve to have more complex body structures, and not more simple ones.