Category: Breaking News
American Entomologist, the new study by George Poinar Jr. from Oregon State University describes beetles preserved in fossilised amber with orchid pollen in their mouths. Pollination is crucial to the reproduction of plants. Pollen grains produced in the anther, the male part of a flower, must be transferred to a stigma: the female part of a flower, of a plant from the same species. Central to this process are pollen vectors, creatures which play a key role in pollination by transporting the pollen between the flowers. Insects are the most common pollen vectors, with bees and butterflies the ones most likely to spring to mind, but certain beetles are also known to pollinate plants. “My paper points out that beetles may play a more important role in pollinating orchids than originally thought, and that they have been doing so for some 20 million years,” said Poinar, in a press release from the Entomological Society of America. Although it is already known that some present day beetles use orchids for nectar, no fossil evidence has ever been found showing beetles pollinating orchids in their evolutionary past. The evidence presented by Poinar’s study is therefore hugely significant. The first specimen in the study was a hidden-snout beetle discovered in amber from the Dominican Republic. After closer analysis, it was found the beetle had pollinaria from an orchid known as Cylindrocites browni attached to its thorax. A second specimen, a toe-winged beetle, was found in amber from Mexico. This time, pollinaria from an orchid described as Annulites mexicana was found attached to the beetle’s mouth parts. It is estimated that the beetle in Dominican amber was alive between 20 and 45 million years ago, while the beetle in Mexican amber is thought to date to between 22 million and 26 million years ago. Curiously, the current day descendants of the two beetles under study are not among the species of beetle usually associated with orchid pollination. No modern day hidden-snout beetles have been seen visiting orchid plants and no toe-winged beetles have been seen with pollinaria. Poinar says that this doesn’t necessarily mean the current-day toe-winged and hidden-snout beetles aren’t involved in pollination. Rather, it’s an anomaly that could be explained by their secretive behaviour, and the difficulty this leads to when it comes to gathering data about them. “While no present-day cryptorhynchid weevils or ptilodactyline beetles are known to carry pollinaria, past and future collections of these and other beetles should be examined to search for attached pollinaria,” Poinar said. “Orchids may have evolved beneficial associations with a much wider range of beetles and other insects than we thought possible.” Image courtesy of Entomological Society of America]]>
Science Daily. Knies is a co-author of a new study that looked to the Arctic for clues as to exactly what slowed the return of life to the world´s oceans. The results of the study illustrate the potential long-term impacts to marine ecosystems of global warming. “What used to be the northwestern continental margin of the supercontinent Pangaea is now Canadian High Arctic. There we found evidence in geological records for a significant nutrient gap during this period. This means that global oceans were severely poor in nutrients such as nitrogen,” Knies says in Science Daily, adding, “The high temperatures caused deepening of the thermocline and nutricline in the ocean so that upwelling of nutrients from the bottom to the surface of ocean ceased. With that the marine algae productivity was stalled.” This nutrient gap was likely caused by the extremely high temperatures of the ocean surface following the extinction event. The planet’s oceans are not just a single layer of water. They consist of boundaries and layers defined by nutrients (nutricline) and temperature (thermocline) among other things. With no algae present, which are at the bottom of the food chain, life in the ocean couldn’t thrive. When the oceans finally began cooling between 6 and 7 million years after the event, the nutrient rich waters returned. “The boundaries that kept the nutrients from reaching the surface were weakened and the ocean waters were mixed. This caused the upwelling of nutrients, resuscitating the oceans, and leading to an explosion of life. The ecosystem voids created by the worst mass extinction in Earth history were finally filled.” Knies explains in Science Daily. The Permian-Triassic mass extinction altered the evolution of both marine and terrestrial life, and made it possible for dinosaurs to evolve. They were left to die off in yet another mass extinction event 66 million years ago. Today there are scientists that contend we’re now facing a new period of mass extinction, caused by human activities for the most part. ]]>
Etruscan Studies. Image courtesy of Mugello Valley Project]]>
Siberian Times, “For such an ancient epoch, this woman has a lot of items in her grave. We have not encountered anything like this in other burials from this time, and it leads us to suggest that the items in her grave had some ritual meaning. We hope to get even more rare and spectacular finds next year, when we will continue to study this unique (burial) mound and open the central burial plot.” The funerary items which had been buried with her include approximately 100 decorations (made with the teeth of various animals), bone and horn carved items, an incense burner, bone needles, jars, and a bronze knife. Additionally, her funeral costume was embellished with more than 1,500 beads. Researchers were particularly excited after the discovery of a clay incense burner because it’s decorated with the same sun-shaped faces previously-discovered on ancient rock art in Siberia. Polyakov explained in the Siberian Times, “Its importance is hard to overestimate. All such images previously discovered had been found only on cliffs or separate stones. Now there is the prospect to find out when they were made,” adding, “Now, thanks to our current research, we can definitely say that these rock arts were made by the representatives of the Okunev culture.” The location where the grave was found is known as the Itkol II burial site. Excavations at the site started in 2008, with around 560 archeologically significant finds unearthed so far. The culture owes its name to the nearby city of Okunev, in the south region of Khakassia, where the first burial site was discovered in 1928. The Okunev Steles, anthropomorphous stone columns which are several meters high, are the most well-known monuments attributed to the Okunev culture. Dr. Polyakov is quoted in the Siberian Times as saying, “Okunev archaeological culture is a unique phenomenon of the Early Bronze Age of Southern Siberia. We have a huge quantity of artistic heritage in the form of numerous images – ‘masks’, carved or engraved on the rocks. They have special style, which is a kind of symbol of Okunev culture.” After the incense burner has been restored and precisely dated it will be exhibited at the Hermitage Museum in St Petersburg. ]]>
The Guardian, Wilkinson made the decision to begin translating the new anthology to close a gap in the modern understanding of ancient Egypt. He was particularly interested in providing access to “the life of the mind, as expressed in the written word” of ancient Egyptians. With writing found on nearly every temple wall and within every tomb, the nearly 3,500 year written tradition of Egypt is much more than decorative. Wilkinson added. The researcher felt that the public were being denied a deep literary tradition, especially with many museums displaying papyrus scrolls covered with hieroglyphs as artifacts instead of texts. The new translations should provide surprises for readers, Wilkinson hopes, adding a much-needed dimension to the ancient people besides pyramids, pharaohs, and Tutankhamun’s famous sarcophagus and mask. While hieroglyphics are pictograms, Wilkinson says that the concepts they convey could be as sophisticated as any Latin or Greek script. The passages he’s chosen to translate offer a glimpse into the life of the ancient Egyptians and are rich with symbolism and metaphor, and include eyewitness accounts of natural disasters and military battles. The researcher, who has written several books on the subject of ancient Egyptians, says that many texts in the collection haven’t been translated for nearly a century. These older translations, only some of which are in English, use diction and idiom that are “very old-fashioned and impenetrable”, Wilkinson said, something that makes it even harder to relate to ancient Egyptians. The problem is not unique to ancient Egyptian; in fact, translating an archaic text into a modern language in a way that provides a close approximation of the original intent without making it unreadable to modern audiences is a dilemma prevalent in many academic translations. However, Wilkinson says that the new translations are much more relatable, even to a modern audience. He attributes this to focusing on the emotional impact of the texts, which are a wide, varied collection of tales that contain literary fiction, correspondence between a farmer and his overseer, and a description of a catastrophic thunderstorm that caused widespread destruction and flooding. The new anthology, which has been titled Writings from Ancient Egypt, is available this week from Penguin Classics. ]]>
Environmental Health Perspectives. Organochlorine chemicals, used in pesticides and insulating material, were banned in 1977. The dangerous compounds were thought to have been confined to history; but the recently published study suggests that they might still be haunting us in the form of a link between higher levels of exposure to the chemicals during pregnancy and an increased risk of autism spectrum disorder in children. The results suggest that children born after being exposed to the highest levels of certain compounds of the chemicals during their mother’s pregnancy were 80% more likely to be diagnosed with autism compared to those who had only been exposed to the very lowest levels of these chemicals. Despite the 1977 US ban on organochlorine chemicals, such as DDT, the compounds remain in the envrionment. Human exposure to the chemicals comes when they are absorbed into animals whose meat make up part of our diet. “There’s a fair amount of research examining exposure to these chemicals during pregnancy in association with other outcomes, like birth weight — but little research on autism, specifically,” said Kristen Lyall, ScD, assistant professor in Drexel University’s A.J. Drexel Autism Institute and the lead author of the study; in a Drexel University press release. “To examine the role of environmental exposures in risk of autism, it is important that samples are collected during time frames with evidence for susceptibility for autism — termed ‘critical windows’ in neurodevelopment. Fetal development is one of those critical windows.” Two different classes of organochlorine chemicals formed the basis of the study: olychlorinated biphenyls (PCBs, which were used as lubricants, coolants and insulators in consumer and electrical products) and organochlorine pesticides (OCPs, which include chemicals like DDT). Rachel Carson’s 1962 book, Silent Spring, documented the detrimental effects pesticides such as DDT had on the environment. It was a watershed moment in the history of environmentalism in the USA, challenging the disinformation propagated by chemical companies and ultimately leading to the ban on DDT and other organochlorines. Lyall and colleagues’ work however, has shown the long term impact of the historical use of these chemicals. “Exposure to PCBs and OCPs is ubiquitous,” said Lyall. “Work from the National Health and Nutrition Examination Survey, which includes pregnant women, shows that people in the U.S. generally still have measurable levels of these chemicals in their bodies.” For the test, participants from a population sample of 1,144 children born in Southern California between 2000 and 2003, were divided into three groups: 545 who were diagnosed with autism spectrum disorder, 181 with intellectual disabilities but no autism diagnosis, and 418 with a diagnosis of neither. Blood tests taken from the second trimester of the mother’s pregnancy were then used to determine the level of exposure to PCBs and OCPs. Lyall stressed that the level of exposure was key in determining risk. “Adverse effects are related to levels of exposure, not just presence or absence of detectable levels,” she said. “In our Southern California study population, we found evidence for modestly increased risk for individuals in the highest 25th percentile of exposure to some of these chemicals.” The consequences of the chemicals were not restricted to autism; the highest exposure to PCBs seemed to double the risk of a child being diagnosed with intellectual disabilities when compared with the cases of the lowest exposure. “The results suggest that prenatal exposure to these chemicals above a certain level may influence neurodevelopment in adverse ways,” Lyall said. The team plan to continue their work, to gain more of an understanding of how chemicals banned decades ago continue to haunt us in the present. “We are definitely doing more research to build on this — including work examining genetics, as well as mixtures of chemicals,” Lyall said. “This investigation draws from a rich dataset and we need more studies like this in autism research.” The full study is available here ]]>