Fossils of six new species of pterosaurs - giant flying reptiles that flew over the heads of the dinosaurs - have been discovered by a research team led by the Milner Centre for Evolution at the University of Bath, revealing that this lineage was killed off in its prime. An analysis of the fossils, published in the open access journal PLOS Biology shows that, contrary to previous studies, there was still remarkable diversity among pterosaurs up to the point of their extinction.

Some of the Moroccan pterosaur fossils from the study. Top: the mandible (lower jaw) of Alcione elainus, a small pterosaur newly described in this paper. Bottom: part of the ulna (forearm bone) from a giant pterosaur, tentatively identified as Arambourgiania. Note the different scales - the mandible is less than 20 cm long, while the ulna is more than 40 cm long; Arambourgiania would have had a wingspan more than three times that of Alcione [Credit: pbio.2001663]

Pterosaurs - prehistoric reptiles popularly known as pterodactyls - were flying cousins of the dinosaurs. Soaring on skin wings supported by a single huge finger, they were the largest animals ever to take wing.

The pterosaurs were previously thought to be declining before the mass extinction at the end of the Cretaceous period, which was caused by an asteroid impact 66 million years ago. However, hundreds of new fossils from the end of the Cretaceous, discovered at sites in northern Morocco, show that the region supported seven species of pterosaur from three different families. It was thought that the rarity of pterosaur fossils from the end of the dinosaur era meant that they were slowly going extinct. But the new study shows that the data had been misleadingly skewed by the dearth of fossils and that the pterosaurs at this time were actually far more diverse than thought.

The new pterosaurs ranged in wingspan from a little over two meters to almost ten meters (from 6 to 30 feet) - almost three times bigger than the largest living bird - and weighed up to 200 kg (440 pounds). The fossils date to just over 66 million years ago, the very end of the Cretaceous period, making these pterosaurs among the last of their kind on Earth. As well as the diversity in size, the authors were also able to show that the species differed significantly in the shape and size of parts of their bodies (such as beak shape, neck length, and wing proportions), suggesting that they occupied distinct ecological niches.

Dr Nick Longrich, from the Milner Centre for Evolution and the Department of Biology & Biochemistry at the University of Bath, and the study's lead author, said: "To grow so large and still be able to fly, pterosaurs evolved incredibly lightweight skeletons, with the bones reduced to thin-walled, hollow tubes like the frame of a carbon-fiber racing bike.

"But unfortunately, that means these bones are fragile, and so almost none survive as fossils."

Longrich said he had always found pterosaurs fascinating, and as a university student had dreamed of studying them. Years later in Morocco, he would stumble across a single, small bone mixed in with fossil fish dug up from a phosphate mine. "It was like a light went off," he said. "I remembered back to the Illustrated Encyclopedia of Pterosaurs, a book I'd practically memorized as an undergraduate. And I thought 'that's a nyctosaur.'"

Nyctosaurs, a family of small pterosaurs, hadn't been proven to survive to the end of the Cretaceous. On a hunch, he looked for more pterosaurs, and found more species - including Tethydraco, a member of the pteranodontids, a family that had been thought to disappear fifteen million years earlier. In addition to the single species previously found in the area, six additional species turned up. "I believe there are many more species to find," he said.

Co-author of the study, Professor David Martill from the University of Portsmouth said: "Exciting discoveries are being made all the time, and sometimes, just the smallest of bones can radically change our perception of the history of life on Earth."

Dr Brian Andres, Research Associate at The University of Texas at Austin, also a co-author of the study, added: "The Moroccan fossils tell the last chapter of the pterosaurs' story - and they tell us pterosaurs dominated the skies over the land and sea, as they had for the previous 150 million years."

Moroccan paleontologist Professor Nour-Eddine Jalil from the Muséum national d'Histoire naturelle, France commented: "This is a fabulous discovery of pterosaurs from Morocco - they tell us their amazing diversity while we thought them in decline. "The Moroccan phosphates are an open window on a key moment in the history of the Earth, one that shortly preceded the global crisis that swept away, among others, dinosaurs and marine reptiles."

Source: Public Library of Science [March 13, 2018]

Morocco’s National Rock Heritage Park has successfully identified more than 400 new archaeological heritage sites across the country.

Credit: Morocco World News

Aiming to study, document, and protect the deep-rooted heritage of Morocco, the park is planning more scientific and archaeological research programs, according to a statement made by the Ministry of Culture.

The park has also contributed to the establishment of excavation programs in the areas of Tata, Tan Tan, Al-Haouz, Aousserd, and other Moroccan regions. Furthermore, it is working to protect rock engravings from plunder and destruction in southern regions, according to the statement.

The Ministry also chaired a series of scientific and communication meetings which aimed to protect rock art sites. These meetings, according to the Ministry, help promote cultural heritage and encourage local and regional authorities to adhere to the program regulations to preserve the sites.

The Ministry also organizes training sessions for local actors that teach preservation of rock heritage, and offer tools and various means to raise awareness for the need to protect the national archaeological sites.

The statement added that the ministry has set up a Provincial Center for the Preservation and Interpretation of Rock Carvings in Tata—a province located in southwestern Morocco.

Recently, the Ministry promoted a draft law which would significantly bolster the protection and preservation of Morocco’s vast cultural heritage.

The Ministry is promising a higher level of consistency in its role of overseeing preservation. Additionally, the strategy integrates newly recognized international concepts of cultural heritage, said the ministry in a statement released by Maghreb Arab Press (MAP).

Author: Safaa Kasraoui | Source: Morocco World News [March 12, 2018]

Researchers from the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, reveal how and when the typical globular brain shape of modern humans evolved. Their analyses based on changes in endocranial size and shape in Homo sapiens fossils show that brain organization, and possibly brain function, evolved gradually within our species and unexpectedly reached modern conditions only recently.

Brain shape evolution in Homo sapiens: brain shape of one of the earliest known members of our species, the 300,000 year-old cranium Jebel Irhoud 1 (left). Brain shape, and possibly brain function, evolved gradually. Brain morphology has reached the globularity typical for present day humans suprisingly recently (right) [Credit: MPI EVA/ S. Neubauer, Ph. Gunz]

The evolutionary history of our own species can be traced back to fossils from Jebel Irhoud (Morocco) dated to about 300,000 years ago. Last year's analysis of these fossils by researchers from the Department of Human Evolution at the Max Planck Institute for Evolutionary Anthropology in Leipzig was highlighted as one of the top science stories of 2017 by a diverse range of print and online media. Together with crania from Florisbad (South Africa, 260,000 years old), and Omo Kibish (Ethiopia) dated to 195,000 years ago, the Jebel Irhoud fossils document an early evolutionary phase of Homo sapiens on the African continent. Their face and teeth look modern, however their elongated braincase appears more archaic as in older human species and in Neanderthals. In contrast, it is a globular braincase, which characterizes the skull of present-day modern humans together with small and gracile faces.

In a new paper published in Science Advances, members of the same research team now reveal additional surprising findings about brain evolution in Homo sapiens. The paleoanthropologists Simon Neubauer, Jean-Jacques Hublin and Philipp Gunz used micro computed tomography scans to create virtual imprints of the internal bony braincase, so called endocasts that approximate brain size and shape. They used state-of-art statistics to analyze endocasts of various fossils and present-day humans.

Evolution of the parietal lobe and the cerebellum

Neubauer and colleagues document a gradual change within Homo sapiens, from an elongated endocranial shape towards a more globular one. Two features of this process stand out: parietal and cerebellar bulging. Parietal brain areas are involved in orientation, attention, perception of stimuli, sensorimotor transformations underlying planning, visuospatial integration, imagery, self-awareness, working and long-term memory, numerical processing, and tool use. The cerebellum is not only associated with motor-related functions like the coordination of movements and balance, but also with spatial processing, working memory, language, social cognition, and affective processing.

The Homo sapiens fossils were found to have increasingly more modern endocranial shapes in accordance with their geological age. Only fossils younger than 35,000 years show the same globular shape as present-day humans, suggesting that modern brain organization evolved some time between 100,000 and 35,000 years ago. Importantly, these shape changes evolved independently of brain size -- with endocranial volumes of around 1,400 milliliters, even the oldest Homo sapiens fossils from Jebel Irhoud fell within present-day variation of brain size. "The brain is arguably the most important organ for the abilities that make us human," says Neubauer. But modern human brain shape was not established at the origin of our species together with other key features of craniodental morphology. Neubauer adds: "We already knew that brain shape must have evolved within our own species, but we were surprised to discover just how recent these changes to brain organization were."

Evolutionary changes in early brain development

In present-day humans, the characteristic globular shape of the braincase develops within a few months around the time of birth. Philipp Gunz explains, "The evolution of endocranial shape within Homo sapiens suggests evolutionary changes of early brain development -- a critical period for neural wiring and cognitive development." The researchers therefore argue that evolutionary changes to early brain development were key to the evolution of human cognition. Jean-Jacques Hublin, co-author and director of the Department of Human Evolution at the Max Planck Institute in Leipzig, says: "The gradual evolution of modern human brain shape seems to parallel the gradual emergence of behavioral modernity as seen from the archeological record."

The new findings are in agreement with recent genetic studies that show changes in genes related to brain development in our lineage since the population split between Homo sapiens and Neanderthals. They add to the accumulating archeological and paleoanthropological evidence demonstrating that Homo sapiens is an evolving species with deep African roots and long-lasting gradual changes in behavioral modernity, brain organization, and potentially brain function.

Source: Max Planck Society [January 25, 2018]