The discovery of new species of Cloudina is important "for understanding the early evolution of animals", states Cortijo, who adds that "its importance for understanding the origin of skeletons is indisputable".
Following is a brief look at some of the theories surrounding them, the octopus fossils themselves and the sites they were found in.
These ancient forms almost certainly do not represent a single line of descent.
Evolution A little background may be of assistance in trying to understand these fossils.
If we travel back in time to the Late Devonian period (408-360m) practically all the cephalopods we would find were the externally-shelled nautiloids.
Going back even further, the oldest known octopus fossil belongs to the Pohlsepia, which lived nearly 300 million years ago.
In the '80s, Spanish researchers found the first fossils of Cloudina in Spain, a small fossil of tubular appearance and one of the first animals that developed an external skeleton between 550 and 543 million years ago.Paleontologist Jørn Hurum supplied Hulsen with ink extracted from a fossil found in Lebanon in 2009, received as a gift from the Pal Venn Museum in 2014.After several millennia Hulson was surprised to find that the color had remained so vibrant, preserved all of this time in the cephalopod’s ink sac.A recent study by researchers from Australia's Environment Institute at the University of Adelaide found that cephalopod populations have increased globally over the last six decades and may actually be benefiting from a changing ocean environment.The scientists attribute cephalopods’ population growth in part to their unique set of biological traits—such as rapid growth and short lifespans—that allow them to adapt quickly to changing conditions.The fossils have been found in the archaeological site El Membrillar (Badajoz), one of the few sites in Europe where remains of Cloudina can be found.