Nature Communications, can be found here Image courtesy of Wits University]]>
Saccorhytus, the miniscule sea creature that resembles nothing so much as a tiny, microscopic sack with a large mouth – a characteristic that some of its descendants today certainly share. The diminutive creature, according to a press release from the University of Cambridge, is the most primitive example to date of a broad biological category of creatures known as deuterostomes. There are several sub-groups under the deuterostome category, including vertebrates. In a recently published research study, scientists from Cambridge, Xi’an China’s Northwest University and other international locations say that Saccorhytus has the honor of being a common ancestor of a massive range of species. Additionally, the deuterostome represents the earliest stage ever discovered regarding the evolution of humans over the course of hundreds of millions of years. There is, of course, nothing even vaguely human when it comes to Saccorhytus. Measuring around a millimeter in size, its habitat was likely the seabed, being small enough to live between individual grains of sand. The microfossil that contained the creature proved to be well-preserved enough for the scientists to make several determinations – including the lack of any orifice for removing waste, such as an anus. In other words, our far-advanced evolutionary predecessor would have expelled waste the same way it came in – unappealing to say the least. One of the main authors of the study, Professor Simon Conway Morris from Cambridge’s St. John’s College, remarked that Saccorhytus looked like nothing so much as tiny black grains to the naked eye. However, under microscope magnification the level of detail preserved by the fossil was nothing less than “jaw-dropping,” the researcher added. Northwest University’s Degan Shu also commented, stating that the research team has a wide array of discoveries to its credit, including a variety of other early deuterostomes like Saccorhytus and also the earliest known instance of what could be classified as a fish. The discovery of the new sea creature, however, provides scientists a glimpse into the very first known evolutionary step of not just humans but also a wide range of related animals, the researcher said. Discovered in China’s central Shanxi Province, the Saccorhytus microfossils have been dated to 540 million years old, a good 20 to 30 million years earlier than the majority of other early deuterostome finds. Researchers were able to construct a picture of how the creature might have looked by isolating the fossils from the surrounding rock and then subjecting them to CT scans and electron microscopy. The amount of limestone the team needed to process in order to access these fossils was massive – approximately three tons, according to co-author Dr. Jian Han, Degan Shu’s colleague at Northwest university. The new research study, which was recently published in the journal Nature, can be found online here Image courtesy of S Conway Morris / Jian Han]]>
Scientific Reports believe the finger can be pointed at climate change. The researchers from the Indiana University-Purdue University Indianapolis used proxies of prehistoric temperature and precipitation preserved in finely layered lake sediments to track the dramatic environmental changes faced by the Mississippians. The lake sediments can be used to map changing climatic conditions in much the same way as tree rings can to detect historical periods of drought. Links appeared between environmental changes, and periods of flourishing or disaster for the Midwestern Native American population. The authors of the study theorise that the extreme climate change they observed likely devastated Mississippian food production, triggering the civilisation’s dramatic disappearance. “Abrupt climate change can impose conditions like drought. If these conditions are severe and sustained, as we have determined that they became for the Mississippians, it is virtually impossible for societies, especially those based on agriculture, to survive,” said corresponding author of the new study, paleoclimatologist Broxton Bird. “From the lake records, we saw that the abundant rainfall and consistent good weather — which supported Mississippian society as it grew — changed, making agriculture unsustainable.” It seems likely that the failure of the Mississippians’ main source of food would have triggered political and social instability, in turn stretching the bonds which held communities together. “Archeologists have recognized that from 1300 onward, Mississippian villages started disappearing –one after the other — almost like lightbulbs in a string, but the question has always been ‘why?,'” said archaeologist Jeremy Wilson, a co-author of the study. “Dr. Bird and his students have shown from the lake-sediment evidence that during the period known as the Little Ice Age, from 1300 to 1800, there was a profound change in climate to colder and drier conditions, which would have negatively impacted the growing of maize in and around Mississippian villages.” The decline of the Mississippians coincided with lower temperatures and reduced rainfall, a consequence of El Nino like conditions in the Pacific Ocean and an overall period of cooling during the little Ice Age. These complicated weather patterns would have ultimately caused drought like conditions in the Midwest. “Climate change had been previously postulated as one of the factors responsible for the disappearance of the Mississippians,” Bird said. “What our research did was develop the highest-resolution record yet produced of rainfall in the midcontinental U.S. for the last 2,100 years, including the time frame from the beginning of the Mississippian period — about 1,000 years ago — to 500 years ago, when much of the lower Midwest was totally abandoned by these people. Our results strongly support climate change — drought, specifically — as a significant cause of the disappearance of Mississippians from the midcontinent through its impact on their ability to farm and produce food surpluses.” Bird suggests that the fate of the Mississippians could provide a valuable lesson for those living and working in the Midwest now. “Mississippians did not have irrigation and relied on rainfall to grow their crops. Modern agriculture in the Midwest corn belt likewise relies on rainfall with very little irrigation infrastructure, making us similarly vulnerable to drought,” The authors of the study are continuing their research at additional lakes in the US Midwest, particularly those close to archaeological sites, in the hope of gaining further insight into the fate of Native American populations. ]]>
Tectonophysics, can be found online at Science Direct Image courtesy of NASA ]]>
Live Science. Since 2012, three amazingly intricate and well-preserved mosaics which once decorated the floor of the older synagogue have been found at the Huqoq site during excavations led by Jodi Magness from the University of North Carolina at Chapel Hill along with Shua Kisilevitz from the Israel Antiquities Authority. The mosaics have since been removed for conservation. ]]>
The Great Wall of China Trump’s proposed wall would pale in comparison to the impressive Great Wall of China, which at its peak measured 13,170.7 miles (21,196.18 km) in length. Even today, what remains of the wall (5,500 miles, 8,851 km) is more than twice the length of the Mexican-US border. Consisting of a series of fortifications and connected walls, the Great Wall of China was first conceived in the third century BCE by Emperor Qin Shi Huang as a means of protecting the Chinese Empire from incursion by barbarian nomads. The most recognisable and well preserved section of the Great Wall was built centuries after the project began, during the Ming Dynasty from the fourteenth to the seventeenth century CE. Although still a powerful symbol of Chinese culture, the Great Wall of China ultimately failed to prevent invaders entering China. In the seventeenth century, Manchus from central and southern Manchuria broke through the wall, attacking Beijing and bringing about the end of the Ming Dynasty and the rise of the Qing Dynasty. Nevertheless, the wall still remains one of the most impressive architectural feats in history. Hadrian’s Wall For nearly 300 years Hadrian’s Wall marked the north-west frontier of the Roman Empire, affording it enormous symbolic as well as defensive importance. The wall’s construction was ordered by Roman Emperor Hadrian on his visit to Britain in 122 CE. At its peak it stretched over 73 miles, crossing northern Britain. The wall had a selection of small castles and towers at regular intervals along its length, meaning there were observation points every third of a mile. Much like the Great Wall of China, Hadrian’s Wall was built as a defensive measure to keep out nomadic tribes, in this instance the Picts of Scotland. In 180 CE, during a major war, a tribe from the north managed to cross over the wall, attacking a fort and killing the Roman general and troops stationed there. The attack likely led to changes in how the wall was manned and its defensive system, but it remained a prominent military installation throughout the Roman occupation of Britain. Following the Roman withdrawal in the fifth century however, Hadrian’s wall started to fall into disrepair, the stones used in its construction being quarried to build castles, churches and houses. The Berlin Wall The most short lived of the three walls, but perhaps the most traumatic for those affected by it. The Berlin Wall was a symbol of the Cold War, and a Europe divided into East and West. Measuring 87 miles long and around 3 metres high, it came to embody a huge cultural divide. In August 1961 the Communist Government of the German Democratic Republic started work on the barbed wire and concrete Antifascistischer Schutzwall (antifascist bulwark) between East and West Berlin. The GDR government claimed the wall was built to prevent ‘western fascists’ attempting to infiltrate East Germany’s socialist society, but in large part its creation was intended to stop the stream of migration west out of the Soviet Union. When completed, the wall embodied the separation of East and West Berlin. Travel between the two sides became virtually impossible, except for diplomats and officials who went through designated checkpoints – the most famous of which was Checkpoint Charlie. On 9th November 1989 the GDR announced that Berliners could once again cross the wall whenever they pleased. An ecstatic atmosphere descended on the city, citizens rushed to climb over the wall, or took pickaxes to it in an attempt to bring it down. 138 people were killed attempting to cross the Berlin Wall over the 28 years of its existence, either by being shot or through accidents associated with their attempts to evade the authorities. The three walls mentioned served their purposes with varying levels of success. Beyond their intended practical uses however, they are so well remembered for the symbolic barriers they represented. It is this that can perhaps provide the biggest insight into the proposed US-Mexico border wall.]]>
Quartenary International. “The discovery sheds new light on regional patterning of art and ornamentation across Europe at a time when the first modern humans to enter Europe dispersed westward and northward across the continent,” said White, in a press release from NYU. Depicting a complicated image involving an aurochs surrounded by a row of dots, the remarkable stone slab was excavated from Abri Blanchard. The site had undergone excavations in the early twentieth century, but starting in 2011 White and his team began a methodical exploration of the remaining deposits. Abri Blanchard is home to artefacts from the Aurignacian culture, a modern human tool making and artistic culture of Upper Paleolithic Europe. A massive diversification and specialisation in tools during the time of the Aurignacian culture (between 43,000 and 38,000 years ago) facilitated its distinctive artwork. In particular, the invention of an engraving tool known as the burin made remarkable rock engravings possible. Although anatomically modern humans first appeared around 100,000 years ago, the Aurignacian culture is widely considered to represent the first modern humans to settle in Europe. Also located in the Vézère Valley, not far from Abri Blanchard, are the Cave Paintings of Lascaux. One of the most famous archeological sites in the world, the Paleolithic cave paintings of Lascaux are remarkable for both their size and the quality of their preservation. Believed to date to sometime around 20,000 years ago, they are among the oldest known cave paintings in existence. White believes that Aurignacian art, such as the stone slab found at the Vézère Valley site, allows us to see into the lives and minds of its creators, and the societies they inhabited. “Following their arrival from Africa, groups of modern humans settled into western and Central Europe, showing a broad commonality in graphic expression against which more regionalized characteristics stand out,” he explained in the NYU press release. “This pattern fits well with social geography models that see art and personal ornamentation as markers of social identity at regional, group, and individual levels.” The oldest known engravings to have been created by a human ancestor date to around 500,000 years ago. A series of zig-zags found on a shell in Java, these markings likely made by Homo erectus constitute the oldest examples of decorative art yet discovered. Abri Blanchard has long been recognised as one of the oldest sites in Europe bearing artefacts of modern human art and symbolism. Since its discovery at the turn of the last century, hundreds of ancient items have been found there, including personal ornaments such as animal teeth, ivory and soapstone beads, pierced shells, paintings and engravings. Image courtesy of Musée national de Préhistoire collections – photo MNP – Ph. Jugie ]]>