Invasive jellyfish turn up in tiny Saanich lake

Darron Kloster / Times Colonist

AUGUST 27, 2020

Craspedacusta, a freshwater jellyfish that is about the size of a thumbnail, can be found in Killarney Lake. The jellyfish are are not harmful to humans and are only visible in lakes a few months of the year. FLORIAN LUSKOW, UBC

A tiny lake in Mount Work Regional Park in Saanich is literally under the microscope today, as scientists from the University of British Columbia study an outbreak of freshwater jellyfish.

Killarney Lake, about a kilometre south of the Hartland Landfill and frequented by swimmers and paddleboarders in summer, has a thriving population of craspedacusta, a freshwater jellyfish considered an invasive species.

The small jellyfish, about the size of a thumbnail, are not harmful to humans and are only visible in lakes a few months of the year, usually from August to September, says Florian Lüskow, a graduate student and marine biologist at UBC.

Lüskow and another researcher collected samples at Killarney Lake on Sunday after a tip from a local resident, launching a small boat loaded with scientific equipment that drew attention from local swimmers.

“They couldn’t believe jellyfish are living in the lake. Most think they live in the ocean,” said Lüskow.

He said there have been several reports of craspedacusta jellyfish in Killarney as well as other lakes and ponds in southern B.C. since 1990.

Lüskow said craspedacusta is a non-indigenous species and likely originates from the Yangtze River catchment area in China.

He said the jellyfish has been recorded on all continents, except for Antarctica.

It is almost impossible to prove how the jellyfish ended up in a lake such as Killarney, said Lüskow.

The invasion could have happened in several ways, he said, including from plant materials,birds’ feet, paddleboards, ballast water from boats, or in containers used to stock lakes with fish.

There have been other reports of the jellyfish in Saanich waterways, including Maltby Lake, two kilometres south of Killarney, in the summer of 2018.

It isn’t known how widespread the jellyfish are in the area. The Capital Regional District parks department did not immediately return calls for comment.

Lüskow said little is known about the jellyfish’s effects in ecosystems. There is no evidence of fish consuming freshwater jellyfish, but they might compete for food resources, Lüskow said in an email.

“As research on this invasive species heavily depends on voluntary observers, only a handful of studies addressed their predation impact.”

Lüskow said for most of the year, jellyfish populations only exist in the form of polyps attached to submerged rocks and tree trunks.

He said freshwater jellyfish are an indication of high water quality. “When lakes and ponds are cooling in the autumn, the free-swimming jellyfish disappear, leaving planktonic larvae that settle onto hard substrates and become polyps,” he said. “When the water warms up, polyps asexually reproduce many free-swimming medusae, which are the sexually reproducing life stage, with a short life span closing the annual jellyfish life cycle.”

Lüskow said a pilot study to understand the distribution and impacts on lake ecosystems in B.C. is underway at UBC.

He said researchers are currently studying another site, Hotel Lake near Sechelt on the Sunshine Coast.

He’s asking anyone who sees them in other lakes, ponds or creeks to send him an email at flueskow@eoas.ubc.ca.

I’m Melting!

POLLUTION DISSOLVED THIS SHARK’S TEETH AND SKIN, RESEARCHERS SAY


Scientists recently found a new victim of climate change and pollution: a blackmouth catshark that had its teeth, skin, and other features dissolved away from swimming in contaminated water.

It’s the first time that scientists have seen such extensive environmental damage on a shark, according to The Evening Standard. The team of University of Cagliari scientists aren’t exactly sure what caused the degradation — it could have been climate change-related ocean acidification, chemical pollution, or both — but it’s a stark reminder of the destruction that human activity is wreaking on the delicate ocean ecosystem.

Toxic Avenger

Thankfully, the shark was able to survive, or at least it did up until last July when it was caught by commercial fishers and promptly turned over to the scientists for study.


The team expected that such extensive damage to the shark’s skin and teeth would be fatal. But they found 14 different sea creatures inside its stomach, according to research published in the Journal of Fish Biology. That suggests that the shark was still able to hunt and swallow prey whole, since its teeth had completely dissolved away.
Extreme Case

This shark is the first known to science with such an extreme level of skin and tooth damage, but scientists have long known that ocean acidification was hurting shark populations.

In fact, previous research found that spending just nine weeks in acidic water ate away nine percent of a shark’s denticles, the tiny scales that line their bodies.


READ MORE: Shark found without skin or teeth in Sardinia ‘fell victim to contaminated waters and climate change’ [The Evening Standard]

More on ocean acidification: Our Acidic Oceans Are Eating Away at Sharks’ Skin

PBS’s Documentary About Ursula K. Le Guin is Free to Watch This Week

Andrew Liptak

Wed Aug 26, 2020

Screenshot: Sheffield Doc/Fest

Last year, PBS released an in-depth documentary about legendary author Ursula K. Le Guin, Worlds of Ursula K. Le Guin, directed by Arwen Curry.

If you missed it the first time around, the network has put the documentary online to stream for free (via Open Culture), until August 30th, 2020.

The hour-long documentary is a deep dive into Le Guin’s career, interviewing not only her, but other authors like Margaret Atwood, Michael Chabon, Neil Gaiman, and David Mitchell. The documentary premiered in 2018, and is part of the American Masters series, a long-running PBS franchise that examines the works of the nation’s most influential artists and creator

Vast stone monuments constructed in Arabia 7,000 years ago

Date:August 25, 2020

Source:Max Planck Institute for the Science of Human History

Summary:New archaeological research in Saudi Arabia documents hundreds of stone structures interpreted as monumental sites where early pastoralists carried out rituals.Share:


In a new study published in The Holocene, researchers from the Max Planck Society in Jena together with Saudi and international collaborators, present the first detailed study of 'mustatil' stone structures in the Arabian Desert. These are vast structures made of stone piled into rectangles, which are some of the oldest large-scale structures in the world. They give insights into how early pastoralists survived in the challenging landscapes of semi-arid Arabia

The last decade has seen rapid development in the archaeology of Saudi Arabia. Recent discoveries range from early hominin sites hundreds of thousands of years old to sites just a few hundred years old. One enigmatic aspect of the archaeological record of western Arabia is the presence of millions of stone structures, where people have piled rocks to make different kinds of structures, ranging from burial tombs to hunting traps. One enigmatic form consists of vast rectangular shapes. Archaeologists working with the AlUla Royal Commission gave these the name 'mustatils,' which is Arabic for rectangle.

Mustatils only occur in northwest Saudi Arabia. They had been previously recognized from satellite imagery and as they were often covered by younger structures, it had been speculated that they might be ancient, perhaps extending back to the Neolithic.

In this new article led by Dr Huw Groucutt (group leader of the Extreme Events Research Group which is a Max Planck group spanning the Max Planck Institutes for Chemical Ecology, the Science of Human History, and Biogeochemistry) an international team of researchers under the auspices of the Green Arabia Project (a large project headed by Prof. Michael Petraglia from the Department of Archaeology at the Max Planck Institute for the Science of Human History and the Saudi Ministry for Tourism as well as collaborators from multiple Saudi and international institutions) conducted the first every detailed study of mustatils. Through a mixture of field survey and analyzing satellite imagery, the team have considerably extended knowledge on these enigmatic stone structures.

More than one hundred new mustatils have been identified around the southern margins of the Nefud Desert, between the cities of Ha'il and Tayma, joining the hundreds previously identified from studies of Google Earth imagery, particularly in the Khaybar area. The team found that these structures typically consist of two large platforms, connected by parallel long walls, sometimes extending over 600 meters in length. The long walls are very low, had no obvious openings and are located in diverse landscape settings. It is also interesting that little in the way of other archaeology -- such as stone tools -- was found around the mustatils. Together these factors suggest that the structures were not simply utilitarian entities for something like water or animal storage.

At one locality the team were able to date the construction of a mustatil to 7000 thousand years ago, by radiocarbon dating charcoal from inside one of the platforms. An assemblage of animal bones was also recovered, which included both wild animals and possibly domestic cattle, although it is possible that the latter are wild auroch. At another mustatil the team found a rock with a geometric pattern painted onto it.

"Our interpretation of mustatils is that they are ritual sites, where groups of people met to perform some kind of currently unknown social activities," says Groucutt. "Perhaps they were sites of animal sacrifices, or feasts."

The fact that sometimes several of the structures were built right next to each other may suggest that the very act of their construction was a kind of social bonding exercise. Northern Arabia 7,000 years ago was very different to today. Rainfall was higher, so much of the area was covered by grassland and there were scattered lakes. Pastoralist groups thrived in this environment, yet it would have been a challenging place to live, with droughts a constant risk.

The team's hypothesis is that mustatils were built as a social mechanism to live in this challenging landscape. They may not be the oldest buildings in the world, but they are on a uniquely large scale for this early period, more than two thousand years before pyramids began to be constructed in Egypt. Mustatils offer fascinating insights into how humans have lived in challenging environments and future studies promise to be extremely useful at understanding these ancient societies.



Related Multimedia:
Images of mustatil structures


Journal Reference:
Huw S Groucutt, Paul S Breeze, Maria Guagnin, Mathew Stewart, Nick Drake, Ceri Shipton, Badr Zahrani, Abdulaziz Al Omarfi, Abdullah M Alsharekh, Michael D Petraglia. Monumental landscapes of the Holocene humid period in Northern Arabia: The mustatil phenomenon. The Holocene, 2020; 095968362095044 DOI: 10.1177/0959683620950449

Max Planck Institute for the Science of Human History. "Vast stone monuments constructed in Arabia 7,000 years ago." ScienceDaily. ScienceDaily, 25 August 2020. .

Atlantic sturgeon in the King’s pantry – unique discovery in Baltic Sea wreck from 1495

Wooden barrel with parts of the sturgeon (in orange) Photo: Brett Seymour

Researchers at Lund University in Sweden can now reveal what the Danish King Hans had planned to offer when laying claim to the Swedish throne in 1495: a two-metre-long Atlantic sturgeon. The well-preserved fish remains were found in a wreck on the bottom of the Baltic Sea last year, and species identification was made possible through DNA analysis.

At midsummer in 1495, the Danish King Hans was en route from Copenhagen to Kalmar, Sweden, on the royal flagship Gribshunden. Onboard were the most prestigious goods the Danish royal court could provide, but then, the trip was also very important. King Hans was going to meet Sten Sture the Elder (he hoped) to lay claim to the Swedish throne. It was important to demonstrate both power and grandeur.

However, when the ship was level with Ronneby in Blekinge, which was Danish territory at the time, a fire broke out on board and Gribshunden sank. The King himself was not on board that night, however, both crew and cargo sank with the ship to the sea floor, where it has lain ever since.

Thanks to the unique environment of the Baltic Sea – with oxygen-free seabeds, low salinity and an absence of shipworms – the wreck was particularly well preserved when it was discovered approximately fifty years ago, and has provided researchers with a unique insight into life on board a royal ship in the late Middle Ages. In addition, researchers now also know what was in the royal pantry – the wooden barrel discovered last year, with fish remains inside.

Bones and scutes from the 500-year old sturgeon (Photo: Brendan Foley)

“It is a really thrilling discovery, as you do not ordinarily find fish in a barrel in this way. For me, as an osteologist, it has been very exciting to work with”, says Stella Macheridis, researcher at the Department of Archaeology and Ancient History at Lund University.

When the remains were discovered it was possible to see that they came from a sturgeon pretty early on due to the special bony plates, the scutes. However, researchers were unsure which species it was. Up until relatively recently, it was believed to be the European sturgeon found in the Baltic Sea at the time. However, the DNA analysis revealed it was the Atlantic variety with which King Hans planned on impressing the Swedes. Researchers have also been able to estimate the length of the sturgeon – two metres – as well as demonstrate how it was cut.

For Maria C Hansson, molecular biologist at Lund University, and the researcher who carried out the DNA analysis, the discovery is of major significance, particularly for her own research on the environment of the Baltic Sea.

“For me, this has been a glimpse of what the Baltic Sea looked like before we interfered with it. Now we know that the Atlantic sturgeon was presumably part of the ecosystem. I think there could be great potential in using underwater DNA in this way to be able to recreate what it looked like previously”, she says.

The Atlantic sturgeon is currently an endangered species and virtually extinct.

Diver examines the wooden barrel (Photo: Brett Seymour)

The discovery on Gribshunden is unique in both the Scandinavian and European contexts –such well preserved and old sturgeon remains have only been discovered a few times at an underwater archaeological site.

It is now possible, in a very specific way, to link the sturgeon to a royal environment – the discovery confirms the high status it had at the time. The fish was coveted for its roe, flesh and swim bladder – the latter could be used to produce a kind of glue (isinglass) that, among other things, was used to produce gold paint.

“The sturgeon in the King’s pantry was a propaganda tool, as was the entire ship. Everything on that ship served a political function, which is another element that makes this discovery particularly interesting. It provides us with important information about this pivotal moment for nation-building in Europe, as politics, religion and economics – indeed, everything – was changing”, says Brendan P. Foley, marine archaeologist at Lund University, and project coordinator for the excavations.

Gribshunden will become the subject of further archaeological excavations and scientific analyses in the coming years.

The research was made possible through a grant from the Crafoord Foundation in Sweden and the Swordspoint Foundation in the USA as well as from Jane and James Orr, Jr. in the USA.

Link to the publication in Journal or Archaeological Science: Reports - Fish in a barrel: Atlantic sturgeon (Acipenser oxyrinchus) from the Baltic Sea wreck of the royal Danish flagship Gribshunden (1495)

First complete dinosaur skeleton ever found is ready for its closeup at last

Date:August 27, 2020

Source:University of Cambridge

The first complete dinosaur skeleton ever identified has finally been studied in detail and found its place in the dinosaur family tree, completing a project that began more than a century and a half ago

The first complete dinosaur skeleton ever identified has finally been studied in detail and found its place in the dinosaur family tree, completing a project that began more than a century and a half ago.

The skeleton of this dinosaur, called Scelidosaurus, was collected more than 160 years ago on west Dorset's Jurassic Coast. The rocks in which it was fossilised are around 193 million years old, close to the dawn of the Age of Dinosaurs.

This remarkable specimen -- the first complete dinosaur skeleton ever recovered -- was sent to Richard Owen at the British Museum, the man who invented the word dinosaur.

So, what did Owen do with this find? He published two short papers on its anatomy, but many details were left unrecorded. Owen did not reconstruct the animal as it might have appeared in life and made no attempt to understand its relationship to other known dinosaurs of the time. In short, he 're-buried' it in the literature of the time, and so it has remained ever since: known, yet obscure and misunderstood.

Over the past three years, Dr David Norman from Cambridge's Department of Earth Sciences has been working to finish the work which Owen started, preparing a detailed description and biological analysis of the skeleton of Scelidosaurus, the original of which is stored at the Natural History Museum in London, with other specimens at Bristol City Museum and the Sedgwick Museum, Cambridge.

The results of Norman's work, published as four separate studies in the Zoological Journal of the Linnean Society of London, not only reconstruct what Scelidosaurus looked like in life, but reveal that it was an early ancestor of ankylosaurs, the armour-plated 'tanks' of the Late Cretaceous Period.

For more than a century, dinosaurs were primarily classified according to the shape of their hip bones: they were either saurischians ('lizard-hipped') or ornithischians ('bird-hipped').

However, in 2017, Norman and his former PhD students Matthew Baron and Paul Barrett argued that these dinosaur family groupings needed to be rearranged, re-defined and re-named. In a study published in Nature, the researchers suggested that bird-hipped dinosaurs and lizard-hipped dinosaurs such as Tyrannosaurus evolved from a common ancestor, potentially overturning more than a century of theory about the evolutionary history of dinosaurs.

Another fact that emerged from their work on dinosaur relationships was that the earliest known ornithischians first appeared in the Early Jurassic Period. "Scelidosaurus is just such a dinosaur and represents a species that appeared at, or close to, the evolutionary 'birth' of the Ornithischia," said Norman, who is a Fellow of Christ's College, Cambridge. "Given that context, what was actually known of Scelidosaurus? The answer is remarkably little!"

Norman has now completed a study of all known material attributable to Scelidosaurus and his research has revealed many firsts.

"Nobody knew that the skull had horns on its back edge," said Norman. "It had several bones that have never been recognised in any other dinosaur. It's also clear from the rough texturing of the skull bones that it was, in life, covered by hardened horny scutes, a little bit like the scutes on the surface of the skulls of living turtles. In fact, its entire body was protected by skin that anchored an array of stud-like bony spikes and plates."

Now that its anatomy is understood, it is possible to examine where Scelidosaurus sits in the dinosaur family tree. It had been regarded for many decades as an early member of the group that included the stegosaurs, including Stegosaurus with its huge bony plates along its spine and a spiky tail, and ankylosaurs, the armour-plated 'tanks' of the dinosaur era, but that was based on a poor understanding of the anatomy of Scelidosaurus. Now it seems that Scelidosaurus is an ancestor of the ankylosaurs alone.

"It is unfortunate that such an important dinosaur, discovered at such a critical time in the early study of dinosaurs, was never properly described," said Norman. "It has now -- at last! -- been described in detail and provides many new and unexpected insights concerning the biology of early dinosaurs and their underlying relationships. It seems a shame that the work was not done earlier but, as they say, better late than never."


Journal Reference:
David B Norman. Scelidosaurus harrisonii (Dinosauria: Ornithischia) from the Early Jurassic of Dorset, England: biology and phylogenetic relationships. Zoological Journal of the Linnean Society, 2020; DOI: 10.1093/zoolinnean/zlaa061

University of Cambridge. "First complete dinosaur skeleton ever found is ready for its closeup at last." ScienceDaily. ScienceDaily, 27 August 2020. .

Fossil evidence of 'hibernation-like' state in 250-million-year-old Antarctic animal

Date:

August 27, 2020

Source:

University of Washington

Summary:

Scientists report evidence of a hibernation-like state in Lystrosaurus, an animal that lived in Antarctica during the Early Triassic, some 250 million years ago. The fossils are the oldest evidence of a hibernation-like state in a vertebrate, and indicate that torpor -- a general term for hibernation and similar states in which animals temporarily lower their metabolic rate to get through a tough season -- arose in vertebrates even before mammals and dinosaurs evolved.

Hibernation is a familiar feature on Earth today. Many animals -- especially those that live close to or within polar regions -- hibernate to get through the tough winter months when food is scarce, temperatures drop and days are dark.

According to new research, this type of adaptation has a long history. In a paper published Aug. 27 in the journal Communications Biology, scientists at the University of Washington and its Burke Museum of Natural History and Culture report evidence of a hibernation-like state in an animal that lived in Antarctica during the Early Triassic, some 250 million years ago.

The creature, a member of the genus Lystrosaurus, was a distant relative of mammals. Antarctica during Lystrosaurus' time lay largely within the Antarctic Circle, like today, and experienced extended periods without sunlight each winter.

The fossils are the oldest evidence of a hibernation-like state in a vertebrate animal, and indicates that torpor -- a general term for hibernation and similar states in which animals temporarily lower their metabolic rate to get through a tough season -- arose in vertebrates even before mammals and dinosaurs evolved.

"Animals that live at or near the poles have always had to cope with the more extreme environments present there," said lead author Megan Whitney, a postdoctoral researcher at Harvard University who conducted this study as a UW doctoral student in biology. "These preliminary findings indicate that entering into a hibernation-like state is not a relatively new type of adaptation. It is an ancient one."

Lystrosaurus lived during a dynamic period of our planet's history, arising just before Earth's largest mass extinction at the end of the Permian Period -- which wiped out about 70% of vertebrate species on land -- and somehow surviving it. The stout, four-legged foragers lived another 5 million years into the subsequent Triassic Period and spread across swathes of Earth's then-single continent, Pangea, which included what is now Antarctica.

"The fact that Lystrosaurus survived the end-Permian mass extinction and had such a wide range in the early Triassic has made them a very well-studied group of animals for understanding survival and adaptation," said co-author Christian Sidor, a UW professor of biology and curator of vertebrate paleontology at the Burke Museum.

Paleontologists today find Lystrosaurus fossils in India, China, Russia, parts of Africa and Antarctica. These squat, stubby, creatures -- most were roughly pig-sized, but some grew 6 to 8 feet long -- had no teeth but bore a pair of tusks in the upper jaw, which they likely employed to forage among ground vegetation and dig for roots and tubers, according to Whitney.

Those tusks made Whitney and Sidor's study possible. Like elephants, Lystrosaurus tusks grew continuously throughout their lives. The cross-sections of fossilized tusks can harbor life-history information about metabolism, growth and stress or strain. Whitney and Sidor compared cross-sections of tusks from six Antarctic Lystrosaurus to cross-sections of four Lystrosaurus from South Africa.

Back in the Triassic, the collection sites in Antarctica were at about 72 degrees south latitude -- well within the Antarctic Circle, at 66.3 degrees south. The collection sites in South Africa were more than 550 miles north during the Triassic at 58-61 degrees south latitude, far outside the Antarctic Circle.

The tusks from the two regions showed similar growth patterns, with layers of dentine deposited in concentric circles like tree rings. But the Antarctic fossils harbored an additional feature that was rare or absent in tusks farther north: closely-spaced, thick rings, which likely indicate periods of less deposition due to prolonged stress, according to the researchers.

"The closest analog we can find to the 'stress marks' that we observed in Antarctic Lystrosaurus tusks are stress marks in teeth associated with hibernation in certain modern animals," said Whitney.

The researchers cannot definitively conclude that Lystrosaurus underwent true hibernation -- which is a specific, weeks-long reduction in metabolism, body temperature and activity. The stress could have been caused by another hibernation-like form of torpor, such as a more short-term reduction in metabolism, according to Sidor.

Lystrosaurus in Antarctica likely needed some form of hibernation-like adaptation to cope with life near the South Pole, said Whitney. Though Earth was much warmer during the Triassic than today -- and parts of Antarctica may have been forested -- plants and animals below the Antarctic Circle would still experience extreme annual variations in the amount of daylight, with the sun absent for long periods in winter.

Many other ancient vertebrates at high latitudes may also have used torpor, including hibernation, to cope with the strains of winter, Whitney said. But many famous extinct animals, including the dinosaurs that evolved and spread after Lystrosaurus died out, don't have teeth that grow continuously.

"To see the specific signs of stress and strain brought on by hibernation, you need to look at something that can fossilize and was growing continuously during the animal's life," said Sidor. "Many animals don't have that, but luckily Lystrosaurus did."

If analysis of additional Antarctic and South African Lystrosaurus fossils confirms this discovery, it may also settle another debate about these ancient, hearty animals.

"Cold-blooded animals often shut down their metabolism entirely during a tough season, but many endothermic or 'warm-blooded' animals that hibernate frequently reactivate their metabolism during the hibernation period," said Whitney. "What we observed in the Antarctic Lystrosaurus tusks fits a pattern of small metabolic 'reactivation events' during a period of stress, which is most similar to what we see in warm-blooded hibernators today."

If so, this distant cousin of mammals isn't just an example of a hearty creature. It is also a reminder that many features of life today may have been around for hundreds of millions of years before humans evolved to observe them.

The research was funded by the National Science Foundation

Journal Reference:
Megan R. Whitney, Christian A. Sidor. Evidence of torpor in the tusks of Lystrosaurus from the Early Triassic of Antarctica. Communications Biology, 2020; 3 (1) DOI: 10.1038/s42003-020-01207-6

University of Washington. "Fossil evidence of 'hibernation-like' state in 250-million-year-old Antarctic animal." ScienceDaily. ScienceDaily, 27 August 2020. .

Newly discovered rare dinosaur embryos show sauropods had rhino-like horns

An incredibly rare dinosaur embryo discovered perfectly preserved inside its egg has shown scientists new details of the development and appearance of sauropods which lived 80 million years ago.

Date:August 27, 2020

Source:University of Manchester

An incredibly rare dinosaur embryo discovered perfectly preserved inside its egg has shown scientists new details of the development and appearance of sauropods which lived 80 million years ago.

Sauropods were the giant herbivores made famous as being 'veggie-saurs' in the 1993 film Jurassic Park. The incredible new find of an intact embryo has shown for the first time that these dinosaurs had stereoscopic vision and a horn on the front of the face which was then lost in adulthood.

The international research team say that this is the most complete and articulate skull known from any titanosaur, the last surviving group of long-necked sauropods and largest land animals known to have ever existed.

The sauropod egg was discovered in Patagonia, Argentina, in an area not previously known to provide evidence of dinosaur fossils. It was imperative the egg was repatriated to Argentina however as it is illegal to permanently remove fossils from the country.

Dr John Nudds from The University of Manchester said: "The preservation of embryonic dinosaurs preserved inside their eggs is extremely rare. Imagine the huge sauropods from Jurassic Park and consider that the tiny skulls of their babies, still inside their eggs, are just a couple of centimetres long.

"We were able to reconstruct the embryonic skull prior to hatching. The embryos possessed a specialised craniofacial anatomy that precedes the post-natal transformation of the skull in adult sauropods. Part of the skull of these embryonic sauropods was extended into an elongated snout or horn, so that they possessed a peculiarly shaped face."

The examination of the amazing specimen enabled the team to revise opinions of how babies of these giant dinosaurs may be hatched and to test previously held ideas about sauropodomorph reproduction. The elongated horn is now thought to have been used as an 'egg tooth' on hatching to allow babies to break through their shell.

The findings, published today in Current Biology, were the result of a novel technique to reveal embryonic dinosaurs in their shells. The embryo within the egg was revealed by carefully dissolving the egg around it using an acid preparation. The team were then able to perform a virtual dissection of the specimen at the European Synchrotron Radiation Facility (ESRF) in Grenoble.

Sauropod embryology remains one of the least explored areas of the life history of dinosaurs. The first definitive discovery of sauropod embryos came with the finding of an enormous nesting ground of titanosaurian dinosaurs discovered in Upper Cretaceous deposits of northern Patagonia, Argentina, 25 years ago. This new discovery however, is the first time a fully intact embryo has been able to be studied.

Other eggs were also found at the Argentinian site which the scientists now aim to examine in a similar fashion. It is thought that some of the eggs could contain well-preserved dinosaur skin which could help further piece together the mysteries of some of the most fascinating animals to ever walk the Earth.


Journal Reference:
Martin Kundrát, Rodolfo A. Coria, Terry W. Manning, Daniel Snitting, Luis M. Chiappe, John Nudds, Per E. Ahlberg. Specialized Craniofacial Anatomy of a Titanosaurian Embryo from Argentina. Current Biology, 2020; DOI: 10.1016/j.cub.2020.07.091

University of Manchester. "Newly discovered rare dinosaur embryos show sauropods had rhino-like horns." ScienceDaily. ScienceDaily, 27 August 2020.

Genetics of the tree of life
Scientists advance genetic understanding of African baobab tree

Summary:Baobab trees can live for more than a thousand years and provide food, livestock fodder, medicinal compounds, and raw materials. Scientists counted the significant tree's chromosomes -- information critical for conservation, agricultural improvement, and further genetic work

Date:August 27, 2020

Source:USDA Forest Service - Southern Research Station

The African baobab tree (Adansonia digitata) is called the tree of life. Baobab trees can live for more than a thousand years and provide food, livestock fodder, medicinal compounds, and raw materials. Baobab trees are incredibly significant. However, there are growing conservation concerns and until now, a lack of genetic information.


The African baobab tree has 168 chromosomes -- critical knowledge for further genetic studies, conservation, and improvement for agricultural purposes. The findings were published in the journal Scientific Reports. Previous studies estimated that the tree has between 96 and 166 chromosomes.

"We were able to unequivocally count the chromosomes," says Nurul Faridi, a USDA Forest Service research geneticist who co-led the study with Hamidou Sakhanokho, a USDA Agricultural Research Service research geneticist.

The researchers used fluorescent probes to see the genetic components of individual chromosomes within the cells -- which glow like jewels.

The analysis also revealed that the tree has a massive nucleolus organizer region (NOR). Relative to the main chromosome body, this region appears larger than that of any other plant species. During certain stages of the cell cycle, nucleoli form at the NORs. The nucleoli are essential for ribosome assembly and protein synthesis in eukaryotes and are an important feature that differentiates eukaryotes from prokaryotes.

"These genetic findings are foundational and will make genetic conservation of the African baobab tree more efficient and effective," says Dana Nelson, a coauthor and project leader of the Southern Research Station's genetic unit. "This research is also a precursor for tree breeding programs seeking to improve baobab for silvicultural applications."

Journal Reference:
Nurul Islam-Faridi, Hamidou F. Sakhanokho, C. Dana Nelson. New chromosome number and cyto-molecular characterization of the African Baobab (Adansonia digitata L.) - 'The Tree of Life'. Scientific Reports, 2020; 10 (1) DOI: 10.1038/s41598-020-68697-6

USDA Forest Service - Southern Research Station. "Genetics of the tree of life: Scientists advance genetic understanding of African baobab tree." ScienceDaily. ScienceDaily, 27 August 2020. .

Antiviral used to treat cat coronavirus also works against SARS-CoV-2

Summary:Researchers are preparing to launch clinical trials of a drug used to cure a deadly disease caused by a coronavirus in cats that they expect will also be effective as a treatment for humans against COVID-19.

Fast-tracked research leads to Phase 1 clinical trials

Date:August 27, 2020

Source:University of Alberta Faculty of Medicine & Dentistry

Researchers at the University of Alberta are preparing to launch clinical trials of a drug used to cure a deadly disease caused by a coronavirus in cats that they expect will also be effective as a treatment for humans against COVID-19.

"In just two months, our results have shown that the drug is effective at inhibiting viral replication in cells with SARS-CoV-2," said Joanne Lemieux, a professor of biochemistry in the Faculty of Medicine & Dentistry.

"This drug is very likely to work in humans, so we're encouraged that it will be an effective antiviral treatment for COVID-19 patients."

The drug is a protease inhibitor that interferes with the virus's ability to replicate, thus ending an infection. Proteases are key to many body functions and are common targets for drugs to treat everything from high blood pressure to cancer and HIV.

First studied by U of A chemist John Vederas and biochemist Michael James following the 2003 outbreak of severe acute respiratory syndrome (SARS), the protease inhibitor was further developed by veterinary researchers who showed it cures a disease that is fatal in cats.

The work to test the drug against the coronavirus that causes COVID-19 was a co-operative effort between four U of A laboratories, run by Lemieux, Vederas, biochemistry professor Howard Young and the founding director of the Li Ka Shing Institute of Virology, Lorne Tyrrell. Some of the experiments were carried out by the Stanford Synchrotron Radiation Lightsource Structural Molecular Biology program.

Their findings were published today in the peer-reviewed journal Nature Communications after first being posted on BioRxIV, a research website.

"There's a rule with COVID research that all results need to be made public immediately," Lemieux said, which is why they were posted before being peer-reviewed.

She said interest in the work is high, with the paper being accessed thousands of times as soon as it was posted.

Lemieux explained that Vederas synthesized the compounds, and Tyrrell tested them against the SARS-CoV-2 virus in test tubes and in human cell lines. The Young and Lemieux groups then revealed the crystal structure of the drug as it binds with the protein.

"We determined the three-dimensional shape of the protease with the drug in the active site pocket, showing the mechanism of inhibition," she said. "This will allow us to develop even more effective drugs."

Lemieux said she will continue to test modifications of the inhibitor to make it an even better fit inside the virus.

But she said the current drug shows enough antiviral action against SARS-CoV-2 to proceed immediately to clinical trials.

"Typically for a drug to go into clinical trials, it has to be confirmed in the lab and then tested in animal models," Lemieux said. "Because this drug has already been used to treat cats with coronavirus, and it's effective with little to no toxicity, it's already passed those stages and this allows us to move forward."

"Because of the strong data that we and others have gathered we're pursuing clinical trials for this drug as an antiviral for COVID-19."

The researchers have established a collaboration with Anivive Life Sciences, a veterinary medicine company that is developing the drug for cats, to produce the quality and quantity of drug needed for human clinical trials. Lemieux said it will likely be tested in Alberta in combination with other promising antivirals such as remdesivir, the first treatment approved for conditional use in some countries including the United States and Canada.

The U of A researchers' work was funded by the Canadian Institutes of Health Research, the Natural Sciences and Engineering Research Council of Canada, Alberta Innovates, Li Ka Shing Institute of Virology and the GSK Chair in Virology.
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Journal Reference:
Wayne Vuong, Muhammad Bashir Khan, Conrad Fischer, Elena Arutyunova, Tess Lamer, Justin Shields, Holly A. Saffran, Ryan T. McKay, Marco J. van Belkum, Michael A. Joyce, Howard S. Young, D. Lorne Tyrrell, John C. Vederas, M. Joanne Lemieux. 

Feline coronavirus drug inhibits the main protease of SARS-CoV-2 and blocks virus replication. Nature Communications, 2020; 11 (1) DOI: 10.1038/s41467-020-18096-2

University of Alberta Faculty of Medicine & Dentistry. "Antiviral used to treat cat coronavirus also works against SARS-CoV-2: Fast-tracked research leads to Phase 1 clinical trials." 

ScienceDaily. ScienceDaily, 27 August 2020. .