2019-12-05 22:30:09
A century and a half ago, in 1859, the exploitation of iron ore, lignite and oil shale began in a quarry in the Sprendlingen forest, near Messel, in west-central Germany, 35 kilometers southeast of Frankfurt. In 1875 the first description of a fossil from the quarry was published: a crocodile discovered by Rudolf Ludwig. The oil shale and the fossils themselves are very fragile, because they contain a lot of water; in a matter of minutes or hours they can crack and crumble when exposed to air, so they should be submerged in water immediately after removal. In 1962, the German paleontologist Oskar Kuhn developed a method, which is still used today, in which the brittle sediment is replaced with an artificial resin without losing the exquisite detail of the fossils.
In 1966, the Hesse State Museum in Darmstadt began carrying out systematic excavations, which coexisted with the commercial exploitation of the quarry until 1971, when it ceased to be profitable and closed. The following year a cement factory established in the quarry also closed; With the abandonment of economic activity, public access was allowed, with which many amateur paleontologists and fossil hunters took advantage of the situation to plunder the site, and many pieces ended up in the hands of private collectors without being properly classified.
In 1975 it was decided to turn the place into a dump, so an emergency campaign was organized to rescue as many fossils as possible before the quarry was covered and inaccessible. Many of the most notable fossils from this site were found in this campaign. In addition to the Hessian museum, the Hessian State Office for the Environment and Geology in Wiesbaden, the Senckenberg Research Institute in Frankfurt and the Leibniz Institute for Applied Geophysics in Hannover participated. But the dump did not come to fruition, and in 1991 the state of Hesse bought the quarry for scientific research. On December 9, 1995, the UNESCO it included the site on its World Heritage list, and an amnesty on irregularly collected fossils was declared in 1996, in the hope that some lost fossils in private collections would surface and become accessible to scientists. One of these fossils was the primate Darwinius masillae, discovered in 1983 and which was in private hands until its acquisition in 2007 by an international group of universities, which announced the discovery to great fanfare two years later as the missing link in the evolution of the lineage of the anthropoids, although it has later been reclassified in the family of the adapids, an extinct group related to the lemurs.
The Messel fossils formed during the middle Eocene, about 47 million years ago. At that time, the region was a subtropical jungle, where conifers, palms, ailanthus, cashews, camellias, citrus fruits, lycopods, ferns and climbing plants grew, which we know from the fossil remains of leaves, fruits, pollen, wood… The grass still was absent.
Fossil schists were formed by the slow deposit of mud and dead vegetation at the bottom of a deep lake, where the absence of oxygen allowed the preservation of fossils in exceptional conditions. The seasonal agitation of the waters caused the upwelling of these oxygen-poor waters towards the surface, which in turn caused a mortality of aquatic flora and fauna that fed the deposit.
The region was also very geologically active, and it has been proposed that the abundance of terrestrial animals at the site could be explained by limnic eruptions such as the one that occurred in 1986 at Lake Nyos in Cameroon, when the sudden release of carbon dioxide into the atmosphere of dissolved carbon in the lake water killed about eighteen hundred people and several thousand head of cattle. Another theory, supported by the presence of trace amounts of toxins in the sediments, points to a seasonal poisoning of the lake waters due to the blooming of cyanobacteria.
Complete, fully articulated skeletons, stomach contents, skins, feathers, soft tissues… have been found at the site in an excellent state of preservation. The Messel fossils have provided unique information on the evolution of mammals. In addition to the aforementioned Darwinius, there are several more species of primitive adapiform primates, ungulates, rodents… Pholidocercus is a primitive hedgehog with a long, thick and scaly tail, and a helmet on its head also made up of scales. Propalaeotherium is a primitive equid, without hooves, between a foot and two feet tall at the withers and about ten kilos in weight, more like a small tapir than a horse. Seven species of bats have been described, which are among the oldest known. One of them is Palaeochiropteryx, an agile flier that uses ultrasound to locate its prey. It has short, broad wings, adapted for flight between trees, with a wingspan of 25 to 30 centimeters, and it feeds mainly on moths and caddisflies, so it was probably nocturnal. The skin, ears and membrane of the wings have been preserved from this bat; from the analysis of the melanosomes in its fur, it has been determined that it was brown in color, like many current bats.
The oldest known pangolin has also been found in Messel: Eomanis, an animal half a meter long that, unlike modern pangolins, had no scales on its legs or tail; From the contents of its stomach we know that it fed on insects and plants. Three-foot-long, scaleless Eurotamandua may also be a primitive pangolin, despite its resemblance to anteaters. Paroodectes is a primitive carnivore of the miácidos family; it is about the size and appearance of a cat, and is adapted to climbing and jumping between trees. Two species of Macronarion are known, related to hedgehogs, moles, and shrews. They are long-tailed and long-legged runners. The largest species, Macronarion tupaiodon, reaches six inches in length, and is covered in dense fur; It is probably omnivorous. The smallest, Macronarion tenerum, is an insectivore with spiny fur and five centimeters in length. A primitive placental is Lepticidium, a bipedal omnivore similar to elephant shrews, with a trunk-shaped snout, hind legs much longer than the front legs, and a long tail; it is not clear if it was a running or jumping animal.
There are also species belonging to groups that are now extinct, such as carnivorous hyenodontids and cymolests, an intermediate group between modern placentals and marsupials. One of these cymolests, Kopidodon, is one of the largest arboreal mammals of its time, and has been preserved with fur. Squirrel-like and 1.15 meters long, including the long, furry tail, it has long canines, probably for defense, and molars adapted for chewing plants. It is also a Buxolestes cimolesto, a semi-aquatic animal about two feet long, similar to an otter.
Among the birds there are small ostriches, chuñas, tiganas, freshwater gannets, trogons, swifts, nictibians, galliformes, hoopoes, mouse birds… Meselaturids are carnivorous birds related to parrots. Palaeoglaux is an owl with curious feathers on its chest. These feathers, one millimeter wide and two millimeters long, are membranous, ribbon-shaped, without beards. Modern birds with similar feathers use them for display, so it is likely that this owl was diurnal. Masillaraptor is a falconiform with long legs and small, weak claws. Fossils of Gastornis have also been found in Messel, the large predatory bird that we have already talked about in Fossil Zoo.
Nine pairs of turtles of the species Allaeochelys crassessculpta, related to the Papuan loggerhead (Carettochelys insculpta), have been found to have died during intercourse. These turtles are able to breathe underwater through their skin; it is assumed that they were mating in the surface waters of the lake when they were suffocated by a gas eruption. There are also crocodiles and alligators up to four meters long, many of them aquatic like their current relatives, but also a terrestrial species, Bergisuchus dietrichbergi, with a short and narrow snout, related to the South American Sebecus that we talked about here a few years ago.
Fossils of boas, lizards, frogs, salamanders and tens of thousands of fish of various species have been found, including predatory alligators measuring one meter in length. Spiders abound, and there are thousands of aquatic and terrestrial insects; in some, the original coloration is still preserved or the structure of the wings can be observed. Most are beetles, but ants, wasps, bugs, bees, cicadas, cockroaches and butterflies also abound. Ants are especially diverse; among them is the largest known ant, Titanomyrma gigantea. Females of this species reached six centimeters in length, one more than the African legionary ants of the genus Dorylus, and a wingspan of about six centimeters. The males were smaller, only three centimeters. In the vein of a fossilized leaf, the characteristic dumbbell-shaped bites of carpenter ants parasitized by the fungus Ophiocordyceps unilateralis have been identified, which modifies the behavior of the ant so that it hangs on the top of a plant before dying. and thus maximize the distribution of the spores of the fungus. It is the oldest proof of this type of parasitism.
In the Messel field, the oil shale layer is nearly two hundred meters thick. Although some twenty million tons of rock have already been extracted, much remains to be explored. Who knows the wonders that are still waiting to be discovered!
CONSTRUCTION OF GERMAN FERNÁNDEZ:
reticular infiltrate
Reticular Infiltrator is the first novel in the trilogy The Saga of the Borelians. Do you want to see how it starts? Here you can read the first two chapters.
The Karnak file. Ed.Rubeo
The hanged man and other fantastic tales. Ed.Rubeo
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