For centuries, fossil remains of different vertebrate animals They have been studied, mainly from their bones or fossilized footprints. But now something has been achieved that a priori seemed impossible; find well preserved soft tissues in ancient fossils.
We call any rest of an organic being already dead that is petrified in certain layers of the Earth’s surface. Under normal conditions, both plants and animals undergo a decomposition process as a consequence of the action of decomposer microorganisms. However, since these remains are buried between rocks, they are protected against the decomposing action of said microorganisms, and isolated from oxygen, which contributes to its good preservation.
Although organisms are usually found partially and not complete, the contribution of these fossil remains is invaluable, since they have allowed us to know more and more about the animal and plant species that have been part of our planet for millions of years, and help us to better understand their evolution. In this post we will talk about three of the most amazing fossil discoveries that have taken place throughout history.
The first fossilized heart of a prehistoric animal
Soft tissues deteriorate rapidly after the death of an organismTherefore, the bacterial interactions that exist between organs begin to break down almost immediately, and what remains buried and could eventually become fossil remains is the skeleton. But certain fossil deposits can be buried under special chemical conditions They are capable of preserving a wide range of soft tissues. It is the case of first full heart of a fish which has been fossilized for almost 120 million years.
The finding was published in the journal elife, where its authors, Jos Xavier-Neto (fromNational Laboratory of Bioscience of Brazil), Lara Maldanis, (from the University of Campinas), Vicente Fernndez, (from European Synchrotron Radiation Facility) and scientists from Sweden explain in detail the method they carried out to recover the organ in question. Through the use ofX-ray tomographic microscope synchrotron source, experts detected not only a heart, but also muscle fibers and parts of the stomach ofRhacolepis, a fish belonging to an already extinct family: Pachyrhizodontidae.
This discovery is very significant, as it shows the condition of the heart valves in the first members of the group of fish with radiated fins (the largest group of vertebrates alive today with about 30,000 species), and its evolution to the current telestets that only have one valve.
The fossil snake that reveals the true color of extinct animals
Research published in the journal Current Biology explains how a team of paleontologists from Spain, Ireland and the United Kingdom have recently discovered the fossil remains of a snake from 10 million years ago. The skin structure of this specimen was so well preserved that it has allowed scientists to decipher a new method to find out the appearance and coloration of some fossil vertebrates, even if they do not have their melanin, thanks to the exceptional preservation of a type of cell that contains the pigments called chromathores. That yes, it is not worth any type of fossil; it must come from an environment whose characteristics have allowed a mineralization as delicate as that of this black-green snake, whose remains are rich in calcium phosphate.
The analysis of the density of this type of cells and of some structures at the subcellular level with electron microscope and its comparison with those of current snakes, has led researchers to determine the color that one day these cells produced in each part of the animal, and thus deduce what evolutionary function they fulfillThe discovery has opened a whole field of study to know the coloration of the great fossils of different species, including dinosaurs from more than 65 million years ago.
The fossils of our old hobby friends
Another spectacular discovery was that of several fossil remains in an Indonesian cave, which revealed a recent relative of modern humans barely a meter tall, so these creatures were quickly nicknamed hobbits. The discovery (made by the Matt Tocheri team at Lakehead University in Thunder Bay, Ontario) and published in Nature, indicates that They disappeared about 50,000 years ago before the Neanderthals.
The real name of these hobbits is Homo floresiensis, for his home on the Indonesian island Flores. With small, chimpanzee-like brains, hobbits they had skulls that resembled those of the Homo erectus, who lived in Africa and Asia. But it also had long arms and short legs, more like much more ancestral ancestors known to the skeleton of Lucy. Although their precise place in the human family tree is not entirely clear, they may have descended from taller ancestors whose stature was eventually diminished by the isolation of shorter individuals on the island. In any case, the discovery of hobbits has meant a turning point for pantheology as we knew it, being a difficult piece to fit into the great puzzle of human evolution.
