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https://www.livescience.com/ A shark's rare "virgin birth" in an Italian aquarium may be the first of its kind, scientists say. The female baby smoothhound shark (Mustelus mustelus) — known as Ispera, or "hope" in Maltese — was recently born at the Cala Gonone Aquarium in Sardinia to a mother that has spent the past decade sharing a tank with one other female and no males, Newsweek reported. This rare phenomenon, known as parthenogenesis, is the result of females' ability to self-fertilize their own eggs in extreme scenarios. Parthenogenesis has been observed in more than 80 vertebrate species — including sharks, fish and reptiles — but this may be the first documented occurrence in a smoothhound shark, according to Newsweek. "It has been documented in quite a few species of sharks and rays now," Demian Chapman, director of the sharks and rays conservation program at Mote Marine Laboratory & Aquarium in Florida, told Live Science. "But it is difficult to detect in the wild, so we really only know about it from captive animals," said Chapman, who has led several studies on shark parthenogenesis. Virgin birth Parthenogenesis may occur infrequently, but it happens in many types of sharks. "About 15 species of sharks and rays are known to do this," Chapman said. But it is likely that most species can probably do it, he added. Scientists notice parthenogenesis occurring most often in carpet sharks, particularly white-spotted bamboo sharks (Chiloscyllium plagiosum) and zebra sharks (Stegostoma tigrinum), because they are common aquarium species. However, parthenogenesis occurs in both oviparous (egg-laying) sharks, like carpet sharks, and viviparous (live-birthing) sharks, like smoothhound sharks, Chapman said. In the wild, parthenogenesis may be a last resort for females that cannot find a mate, either because they have been separated from others in their species or because human impacts, such as climate change and overfishing, or natural selection pressures, such as predation and disease, have wiped out all the available males. In aquariums, separation from males or long periods of isolation can trigger this natural response in females, Chapman said. Some individual sharks have been observed repeatedly giving birth via parthenogenesis over a period of years, and others may switch between parthenogenesis and sexual reproduction when introduced to a mate, Chapman said. Imperfect cloning There are two types of parthenogenesis: apomixis, a form of cloning common among plants, and automixis, a form of self-fertilization that more closely resembles sexual reproduction, according to National Geographic. "Rather than combining with a sperm cell to make an embryo, [the egg cell] combines with a polar body, which is essentially another cell that is produced at the same time that the egg cell is produced and has the complementary DNA," Christine Dudgeon, a biosciences researcher at the University of Queensland in Australia who has studied shark parthenogenesis, told Live Science. In this scenario, the polar body acts as a pseudo-sperm cell with a single strand of DNA. The resulting offspring get 100% of their their DNA from their mother but are not exact clones of them, Dudgeon said. This is because sex cells, also known as gametes, have a unique combination of genes that are randomly selected from each parent as they are created — so each shark egg (or polar body) has a different genetic makeup. When the polar body and egg combine, they produce a baby shark that is genetically different from the mother. But because they are only made from one gamete , not two, parthenogenetic offspring are more closely related to their mother than normal babies are, Dudgeon said. Because parthenogenesis in sharks happens only in females and females cannot pass on a Y chromosome, it also means the resulting offspring are always female. "The mother is XX, and so she will only pass on X chromosomes to the offspring," Dudgeon said. Health issues "Parthenogenesis is essentially a form of inbreeding, as the genetic diversity of the offspring is greatly reduced," Dudgeon said. As such, offspring produced by parthenogenesis may have a reduced chance of survival, Dudgeon added. "There is a high rate of embryonic failure among parthenogenetic offspring," Chapman said. "But when they do survive, many have normal lives, and some can even reproduce." However, it is hard to pin down exactly why baby sharks die, whether they are parthenogenetic or not. "Mortality in young sharks in aquaria, and the wild, is common, so it's hard to say what is causing it," Dudgeon said. "The [normal] offspring that are born have already won the lottery," she added. Baby Ispera appears to be in good health and is expected to live a relatively normal life in captivity, according to Newsweek.

https://www.bbc.com/news A major review of vaccines suggests the AstraZeneca jab does raise the risk of blood clots and another serious condition that can cause bleeding. But the study found the risk of such problems following a coronavirus infection was still much higher. The University of Oxford-led team also found an increased risk of stroke after the Pfizer jab - but again at a much lower rate than after infection. The team said it once again showed the "substantial" benefit of vaccination. It comes after a coroner ruled on Thursday that BBC Radio Newcastle presenter Lisa Shaw died because of complications from the AstraZeneca jab. The 44-year-old died in May after developing headaches a week after getting her first dose. She suffered blood clots in the brain. Child jabs halted in trial as adult clot link probed AstraZeneca: Is there a blood clot risk? The research team looked at records from more than 29 million people who received a first dose of a Covid vaccine between December and April, as well as nearly 1.8 million who were infected with the virus. The study, published in the British Medical Journal, looked for complications up to 28 days after being jabbed or infected. It found that for every 10 million people vaccinated with the AstraZeneca vaccine: an extra 107 would be hospitalised or die from thrombocytopenia, which can cause internal bleeding and haemorrhages, but that was nearly nine times lower than the risk of the same condition following an infection an extra 66 would be hospitalised or die from blood clots in the veins, but that was nearly 200 times lower than the risk following an infection For every 10 million people vaccinated with the Pfizer vaccine, it found: 143 extra strokes would be seen, but that was nearly 12 times lower than the risk following an infection Lead author Prof Julia Hippisley-Cox said it was important people were aware of the risks, but that they were kept in context given the higher risk from being infected. Fellow author Prof Aziz Sheikh added the findings "clearly underscore" the importance of getting vaccinated to reduce the risk of these clotting and bleeding outcomes. Vaccinations, he said, offer a "substantial public health benefit".

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Argon Forty, makers of fine Raspberry Pi casings such as the Argon ONE M.2 and the excellent Argon NEO has announced a Kickstarter campaign for the Argon EON, a four-bay network storage array powered by your choice of Raspberry Pi 4. The Argon EON, is a tall triangular NAS enclosure which stands like an open book, with an exterior made from a glossy black plastic. That, however, is all we know about the mysterious data depository - the makers have yet to reveal any information beyond a brief statement to Kickstarter members: "We will be launching our latest project on Kickstarter on 09 September 2021, and we decided to let you know in advance as you are one of our avid supporters. Argon EON is a four-Bay SATA enclosure that allows you to connect four storage drives, two 3.5" HDD and two 2.5" HDD or SSD. It will be powered by the Raspberry Pi 4 of your choice. “It is again a build-your-own system much like the Argon ONE and Argon ONE M.2. We believe that letting you the makers enjoy the build is part of the experience that makes using the Raspberry Pi great." As yet, we have no idea whether the EON will require a tool to access its drive bays, nor do we know of the prices per pledge - you will certainly need to supply your own Pi board and drives, though some sort of bundle seems possible - and software support will be just as important as the construction of the hardware. The Kickstarter campaign starts on September 9 and you can register for updates at the pre-launch page. We have reached out to Argon Forty for more information.

https://www.bbc.com/news Japan has suspended the use of about 1.63 million doses of the Moderna vaccine due to contamination. The health ministry said "foreign materials" were found in some doses of a batch of roughly 560,000 vials. Takeda Pharmaceutical, which sells and distributes the vaccine in Japan, said Moderna had put three batches on hold "out of an abundance of caution". It said an issue at a manufacturing contract site in Spain was the likely cause, but did not elaborate. "To date, no safety or efficacy issues have been identified," Moderna said, adding that it would work with regulators and Takeda to investigate the matter further. There are no details of what the "foreign objects" are, but Takeda described it as particulate matter, after which it said conducted an emergency examination. Reports of contamination also came from seven other vaccination centres, according to the Japan Times newspaper, with 39 vials - or 390 doses - found to have been affected. The health ministry has published the batch numbers so that people who had received their shot before the suspension could check if they have got a potentially contaminated shot, Japan Times added. Japan is battling a spike in Covid cases, with eight more prefectures placed under a state of emergency on Wednesday. It's capital Tokyo, is currently hosting the Paralympic Games. The country has already approved the Pfizer and AstraZeneca vaccines for use - it only started using Moderna in May. Just over 40% of Japanese people are fully vaccinated and around 50% have received one dose.

https://www.livescience.com/ A semiaquatic whale that lived 43 million years ago was so fearsome, paleontologists have named it after Anubis, the ancient Egyptian god of death. The newly discovered 10-foot-long (3 meters) species, dubbed Phiomicetus anubis, was a beast; When it was alive more than 43 million years ago, it both walked on land and swam in the water and had powerful jaw muscles that would have allowed it to easily chomp down on prey, such as crocodiles and small mammals, including the calves of other whale species. What's more, the whale's skull bears a resemblance to the skull of the jackal-headed Anubis, giving it another link to the death deity, the researchers observed. "It was a successful, active predator," study lead author Abdullah Gohar, a graduate student of vertebrate paleontology at Mansoura University in Egypt, told Live Science. "I think it was the god of death for most animals that lived alongside it." Although today's whales live in the water, their ancestors started out on land and gradually evolved into sea creatures. The earliest known whale, the wolf-size Pakicetus attocki, lived about 50 million years ago in what is now Pakistan. The new discovery of P. anubis sheds more light on whale evolution, said Jonathan Geisler, an associate professor of anatomy at the New York Institute of Technology who was not involved with the study. "This fossil really starts to give us a sense of when whales moved out of the Indo-Pakistan ocean region and started dispersing across the world," Geisler told Live Science. Paleontologists discovered the fossil remains of P. anubis in 2008, during an expedition in Egypt's Fayum Depression — an area famous for sea life fossils, including those of sea cows and whales, dating to the Eocene epoch (56 million to 33.9 million years ago). The expedition was led by study co-researcher Mohamed Sameh Antar, a vertebrate paleontologist with the Egyptian Environmental Affairs Agency, making this the first time that an Arab team has discovered, scientifically described and named a new species of fossil whale, Gohar said. By analyzing the whale's partial remains — pieces of its skull, jaws, teeth, vertebrae and ribs — the team discovered that the 1,300-pound (600 kilogram) P. anubis is the earliest (or most "primitive") whale in Africa from a group of semiaquatic whales known as the protocetids. P. anubis's remains revealed that the protocetid whales had evolved a few new anatomical features and feeding strategies. For instance, P. anubis had long third incisors next to its canines, "which suggests that incisors and canines were used to catch, debilitate and retain faster and more elusive prey items (e.g. fish) before they were moved to the cheek teeth to be chewed into smaller pieces and swallowed," the researchers wrote in the study. Advertisement Moreover, big muscles on its head would have given it a powerful bite force, allowing it to capture large prey through snapping and biting. "We discovered how [its] fierce, deadly and powerful jaws were capable of tearing a wide range of prey," Gohar said. P. anubis wasn't the only fossil whale from the middle Eocene of Egypt. Its fossils came from the same area as a previously discovered Rayanistes afer, an early aquatic whale. This finding suggests that the two early whales lived in the same time and place, but likely occupied different niches. It's even possible that P. anubis hunted R. afer calves, making its "Anubis" name all the more appropriate, Gohar said. Granted, to some animals, P. anubis was prey. The ribs of the newly described whale have bite marks that "suggest it was once bitten severely by sharks," Gohar said. However the marks indicate that the sharks were small, and likely not large enough to kill the whale; rather, these sharks were likely scavenging its carcass.

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