понедельник, 6 мая 2019 г.

Fusing Fronts From your skin to your gut, tissue barriers are…

Fusing Fronts

From your skin to your gut, tissue barriers are essential for a healthy, working body, whether it’s keeping the bad stuff out or the good stuff in. Researchers probed the dynamics of how tissue barriers form during development using fruit flies. Focusing on the formation of epithelial barriers, they fluorescently tagged actin, a protein that forms part of a cell’s architecture, in epithelial cells and imaged sheets of these cells fusing together in real-time (pictured). This revealed that the cells in the flanks of fusing sheets changed in number and geometry to ensure fusion remained steady and even. What’s more, they found that fusing cells came together front-on at the point of fusion but upon completion of fusion took on an interlocking pattern. Together these insights reveal how strong, stable seals can form to produce robust tissue barriers.

Written by Lux Fatimathas

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Astronaut Commands Robotic Arm to Capture Dragon Cargo Craft

SpaceX — Dragon CRS-17 Mission patch.

May 6, 2019

While the International Space Station was traveling over the north Atlantic Ocean, astronauts David Saint-Jacques of the Canadian Space Agency and Nick Hague of NASA grappled Dragon at 7:01 a.m. EDT using the space station’s robotic arm Canadarm2.

Ground controllers will now send commands to begin the robotic installation of the spacecraft on bottom of the station’s Harmony module. NASA Television coverage of installation is scheduled to begin at 9 a.m. Watch online at http://www.nasa.gov/live.

Image above: The SpaceX Dragon CRS-17 Cargo Craft captured and attached to the CanadaArm2. Image Credit: NASA TV.

The Dragon lifted off on a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida Saturday, May 4 with more than 5,500 pounds of research, equipment, cargo and supplies that will support dozens of investigations aboard the orbiting laboratory.

Here’s some of the research arriving at station:

NASA’s Orbiting Carbon Observatory-3 (OCO-3) examines the complex dynamics of Earth’s atmospheric carbon cycle by collecting measurements to track variations in a specific type of atmospheric carbon dioxide. Understanding carbon sources can aid in forecasting increased atmospheric heat retention and reduce its long-term risks.

SpaceX CRS-17: Dragon capture

The Photobioreactor investigation aims to demonstrate how microalgae can be used together with existing life support systems on the space station to improve recycling of resources. The cultivation of microalgae for food, and as part of a life support system to generate oxygen and consume carbon dioxide, could be helpful in future long-duration exploration missions, as it could reduce the amount of consumables required from Earth.

Related articles:

SpaceX Dragon Heads to Space Station After Successful Launch

Drone Ship Power Issue Forces Scrub of CRS-17 Launch

Hermes to Bring Asteroid Research to the ISS

Dragon’s 17th Flight Carries Science to the Space Station

Related links:

Orbiting Carbon Observatory-3 (OCO-3): https://ocov3.jpl.nasa.gov/

Photobioreactor: https://www.nasa.gov/mission_pages/station/research/news/photobioreactor-better-life-support

SpaceX: http://www.nasa.gov/spacex

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

For updates during the mission, visit https://www.nasa.gov/commercialresupply.

Image (mentioned), Video, Text, Credits: NASA/Norah Moran/NASA TV/SciNews.

Greetibgs, Orbiter.chArchive link

2019 May 6 Virtual Flyby of the Whirlpool Galaxy Video Credit:…

2019 May 6

Virtual Flyby of the Whirlpool Galaxy
Video Credit: F. Summers, J. DePasquale, and D. Player (STScI); Music: Into the Wormhole (Jingle Punks via Youtube)

Explanation: What would it look like to fly over a spiral galaxy? To help visualize this, astronomers and animators at the Space Telescope Science Institute computed a virtual flyby of the Whirlpool Galaxy (M51) using data and images from the Hubble Space Telescope. At only 25 million light years distant and fully 50 thousand light years across, the Whirlpool is one of the brightest and most picturesque galaxies on the sky. Visible during the virtual flyby are spiral arms dominated by young blue stars, older lighter-colored stars, dark lanes of dust, and bright red emission nebulae. Many galaxies far in the distance can be seen right through M51. The visualization should be considered a time-lapse, because otherwise the speed of the virtual camera would need to be very near the speed of light.

∞ Source: apod.nasa.gov/apod/ap190506.html

Whithorn Story Reconstructed Iron Age Roundhouse, Whithorn, Dumfries and Galloway,...

Whithorn Story Reconstructed Iron Age Roundhouse, Whithorn, Dumfries and Galloway, Scotland, 5.5.19.

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Traces of Alexander city found in Swat

The archaeologists have found the traces of the second missing city of Bazira that was established after the destruction of the lower city in the third century by a catastrophic earthquake.

Traces of Alexander city found in Swat
Barikot, Area BKG 11 [Credit: MAIP/ISMEO]

The ancient Bazira is also known as the city of Alexander. The discovery occurred during the recent excavations in Barikot-Swat.

“Luckily we have found that missing gap. After the abandonment of the lower city in the third century, a smaller but complex urban settlement was rebuilt at the foot of Barikot Ghwandai,” Dr Luca Maria Olivieri, head of the Italian Archaeological Mission, told Dawn.

He said that archaeologists found not only the Hindu Shahi structure but also the traces of a small urban settlement and a citadel, which had been inhabited since the fourth century till the Ghaznavid time.

“The lower city, abandoned after a massive earthquake in the third century, was known as Bazira or Beira. The newly discovered city, according to an inscription found on the top of the Ghwandai, was called Vajirasthana. It means the fortified place of Bazira,” said Dr Luca.

Traces of Alexander city found in Swat
Barikot, excavation of trench K 105 [Credit: MAIP/ISMEO]

He said that the most important and evident remains of the citadel were a fire temple, a Hindu Shahi fortress or palace, both coeval to a Hindu Shahi temple discovered in 1988 on the top of the Ghwandai.

The archaeologists found the scattered evidence of the Ghaznavid period and also the evidence of Medieval Dardic village (dated to 12th to 15th century AD) that was ultimately occupied by the Yousafzai tribe.

According to oral histories reported both from Barikot-Swat and Barikot-Dir, by a British officer in 1912, the original inhabitants of the area fled to Dir with their own chief Barya Khan and founded a new Barikot there.

Local and foreign tourists also started visiting the newly discovered site and term it an amazing addition to the realm of Gandhara civilisation.

Traces of Alexander city found in Swat
Excavation in progress in Barikot [Credit: MAIP/ISMEO]

Nattapach, a tourist, who visited the site with a group of other Thai tourists, said that he was excited to see such amazing archaeological sites. “It was a big city having a rich history,” he told Dawn, adding that Pakistan was the home of early Buddhism and it was important for Buddhists around the world.
Kampira, another Thai tourist, said that she learnt that the early Buddhists living in Gandhara region were the first to have introduced the image of Buddha that’s why she always wanted to visit Gandhara.

“Luckily I got the opportunity to visit Gandhara in Pakistan this time. I am happy and content to visit so many ancient Buddhist sites including ancient stupas, monasteries and statues,” she said.

Author: Fazal Khaliq | Source: Dawn [May 01, 2019]



Petra region still holds ‘completely untapped potential’ for archaeologists

In contrast with the area of Wadi Musa, Beidha is still free from modern development, so the natural landscape is still unspoiled and the archaeological heritage is still accessible to researchers, according to an Italian archaeologist.

Petra region still holds ‘completely untapped potential’ for archaeologists
One of two mosques found in Beidha, near Petra [Credit: Micaela Sinibaldi]

“The Beidha region is ideal to conduct archaeological research in the Petra region, since it has an almost completely untapped potential for a complete understanding of settlements patterns in the history of the whole Petra region,” Micaela Sinibaldi recently said during a lecture at the American Centre of Oriental Research titled, “Islamic Baydha Project”.

The project was established in 2014 under Sinibaldi’s direction, and her team has so far excavated one habitation and two mosques, Sinibaldi noted.

According to the archaeologist, the two mosques are the first ever discovered and excavated in Petra and are associated with a large village.

“They [the mosques] could both hold about 50 worshippers, and they were built with very similar methods, including a large reuse of Nabataean materials, non-rectilinear walls bound with mud mortar and a lack of a specific building style,” Sinibaldi elaborated.

Petra region still holds ‘completely untapped potential’ for archaeologists
Excavation in progress at mosque site in Beidha, near Petra [Credit: Islamic Baydha Project]

Furthermore, differences between the two mosques included different directions of the arches and different proportions in the top plan, she said, adding that one of the mosques was decorated with white and red plaster.

“The analysis of the walls… has made it possible to show in detail the phases and methods of construction of the mosque,” Sinibaldi underlined.

The lack of coins or inscriptions or well dated materials will require more study before expressing a interpretation for the mosques, Sinibaldi explained, saying that ceramic remains were very scarce, and the building style of the mosques was strikingly similar to the one used in contemporary villages in the south Jordan.

However, a few well-dated materials were found in the village houses, which may be chronologically related, Sinibaldi continued, adding that “this adds to growing evidence for a Mamluk period in Petra, especially the 13th-14th centuries.”

Petra region still holds ‘completely untapped potential’ for archaeologists
Preparing for the backfill by laying jute textile on the floor of one of two mosques found in Beidha
[Credit: Islamic Baydha Project]

Sinibaldi also highlighted the project’s relationship with the local community: “Understanding the local, recent and modern material culture is an important approach of this project’s research aspect because of the longevity of the local material culture. This is facilitated by taking information from the local community,” she said.

“The Islamic Bayda Project also includes a training programme in archaeological fieldwork, designed for Jordanian and international trainees. My hopes for the future of the project are that funds will be raised for the conservation of the mosques, in order to make it accessible to the public, and the future of the site will be planned on an idea of sustainable tourism and the full respect of both the rich archaeological and natural heritage of the site,” Sinibaldi concluded.

Author: Saeb Rawashdeh | Source: The Jordan Times [May 01, 2019]



System of globular clusters in disc of galaxy detected for first time

An international scientific team led by a Mexican researcher discovered globular clusters rotating at the same speed as the gas in the disk of the spiral galaxy Messier 106 (also known as M106 or NGC 4258) to which they belong. Because of their disk-like arrangement and speed, these distant objects could be relics of cosmic high noon.

System of globular clusters in disc of galaxy detected for first time
False colour image of M106. The image combines neutral hydrogen data (blue) from the WSRT with optical data
 (red and green) from the CFHT. Yellow circles highlight the observed globular clusters, which are distributed
 in a rotating disk whose velocity is the same as that of the neutral gas [Credit: 
Divakara Mayya, INAOE/Instituto de Radioastronomía y Astrofísica]

This research was carried out using the Gran Telescopio Canarias (GTC), of which Mexico is a partner, and the results were published in The Astrophysical Journal.

Dr. Rosa Amelia González-Lópezlira, researcher at the Institute of Radio Astronomy and Astrophysics of the National Autonomous University of Mexico, Campus Morelia (IRyA-UNAM), is leading this project. The second author of the article is Dr. Divakara Mayya, a researcher at the National Institute of Astrophysics, Optics and Electronics (INAOE). The working group includes researchers and students in Australia, Brazil, Chile, Denmark, France, and Germany, in addition to other colleagues at the IRyA-UNAM and INAOE.

Dr. González-Lópezlira explains that globular clusters are groups of between 100,000 and 1 million stars. They are common objects, especially in large galaxies. «The Milky Way has 160 of these clusters, but very large galaxies can have tens of thousands. Usually, these clusters are distributed as in a sphere. All the stars of a globular cluster are approximately of the same age and have more or less the same chemical composition. We do not know exactly how these clusters were formed, and there are several hypotheses that try to explain it: one says that they precede the formation of galaxies, another one that clusters formed along with them, yet another postulates that some appear when gas collides during a galaxy merger,» she says.

In the Milky Way, for example, most of the globular clusters seem to have formed together with the galaxy; a few were formed or acquired later, when one or several smaller galaxies merged with it.

Globular clusters are very old objects that formed about 11.5 billion years ago, 2.3 billion years after the Big Bang and shortly before the rate of cosmic star formation reached its peak, 10 billion years ago. «This period is known as cosmic high noon. The clusters are very bright and can be seen at very large distances, which means that they can give us clues as to how the galaxies were assembled during this period of maximum star formation,» says the astrophysicist.

The article that was published in the May 1st issue of the ApJ is part of a larger project to study the globular cluster systems of nine spiral galaxies within a radius of 52 million light-years. «We are particularly interested in the relationship between the number of globular clusters and the mass of the central black hole in spiral galaxies,» says the researcher. The relationship is very tight for elliptical galaxies, but it is not as clear in spiral galaxies. The Milky Way, for example, does not fulfill it. Dr. González-Lópezlira adds: «The nine spiral galaxies that we are going to study have good estimates of the masses of their black holes and are at distances where the globular clusters can be seen well with the Canada-France-Hawaii Telescope (CFHT), with which we made the initial observations.»

Dr. Divakara Mayya explains that these kinds of studies begin by taking images and finding globular cluster candidates based on so-called color-color diagrams. In this case, in addition to an optical filter, an ultraviolet and an infrared filter were used, which is not common. «Candidates are selected in these diagrams, but other apparently point sources, like stars and faraway galaxies, can seep in. Therefore, spectra confirm that each object has an old coeval population, and that its recession velocity is compatible with the recession velocity of the galaxy to which it is supposed to belong. We use OSIRIS in the GTC because these objects are quite far away, and therefore exposures of more than one hour with the largest optical telescope in the world are needed to extract the information from the spectra. OSIRIS is a multiobject spectrograph with which one can observe several objects at once. We observed a total of 23 globular cluster candidates in two fields.»

The main finding of the project was totally unexpected and surprising. Instead of being distributed in a sphere, «the globular clusters of NGC 4258 seem to be arranged in a disk that rotates in phase and practically as fast as the neutral hydrogen (HI) gaseous disk of the galaxy, which was observed with the Westerbork Synthesis Radio Telescope (WSRT), even at great distances from its center. This has never been seen before. Those are apparently the facts, although one must continue working to confirm them. This is one of the very nice things that can happen when working in science,» says Dr. Mayya.

Dr. González-Lópezlira says that because of the way in which the M106 clusters move, the disk where they are distributed is very similar to the disks where we see that stars were forming 10 billion years ago. «We speculate that the disk of clusters of M106 is a relic or remnant of cosmic high noon.»

The researchers further corroborated with the GTC that M106 does fall in the correlation between number of globular clusters and black hole mass, and that their photometric method to find globular clusters is excellent. The supermassive black hole at the center of M106 weighs 40 million solar masses, 10 times more than that of the Milky Way’s and 150 times less than Messier 87’s, whose image was recently released.

Finally, the IRyA-UNAM researcher added that studies like this in more spiral galaxies will clarify the role of the several proposed hypotheses in the assembly of galaxies, their globular cluster systems and their black holes.

Source: Instituto de Radioastronomía y Astrofísica [May 02, 2019]



When it comes to planetary habitability, it’s what’s inside that counts

Which of Earth’s features were essential for the origin and sustenance of life? And how do scientists identify those features on other worlds?

When it comes to planetary habitability, it's what's inside that counts
Artist’s impression shows a view of the surface of the planet Proxima b orbiting the red dwarf star Proxima Centauri,
the closest star to the Solar System [Credit: ESO/M. Kornmesser]

A team of investigators with array of expertise ranging from geochemistry to planetary science to astronomy published in Science urging the research community to recognize the vital importance of a planet’s interior dynamics in creating an environment that’s hospitable for life.

With our existing capabilities, observing an exoplanet’s atmospheric composition will be the first way to search for signatures of life elsewhere. However, Carnegie’s Anat Shahar, Peter Driscoll, Alycia Weinberger, and George Cody argue that a true picture of planetary habitability must consider how a planet’s atmosphere is linked to and shaped by what’s happening in its interior.

For example, on Earth, plate tectonics are crucial for maintaining a surface climate where life can thrive. What’s more, without the cycling of material between its surface and interior, the convection that drives the Earth’s magnetic field would not be possible and without a magnetic field, we would be bombarded by cosmic radiation.

«We need a better understanding of how a planet’s composition and interior influence its habitability, starting with Earth,» Shahar said. «This can be used to guide the search for exoplanets and star systems where life could thrive, signatures of which could be detected by telescopes.»

When it comes to planetary habitability, it's what's inside that counts
An artist’s impression of the surface of the super-Earth Barnard’s Star b
[Credit: ESO/M. Kornmesser]

It all starts with the formation process. Planets are born from the rotating ring of dust and gas that surrounds a young star. The elemental building blocks from which rocky planets form—silicon, magnesium, oxygen, carbon, iron, and hydrogen—are universal. But their abundances and the heating and cooling they experience in their youth will affect their interior chemistry and, in turn, things like ocean volume and atmospheric composition.

«One of the big questions we need to ask is whether the geologic and dynamic features that make our home planet habitable can be produced on planets with different compositions,» Driscoll explained.

The Carnegie colleagues assert that the search for extraterrestrial life must be guided by an interdisciplinary approach that combines astronomical observations, laboratory experiments of planetary interior conditions, and mathematical modeling and simulations.

«Carnegie scientists are long-established world leaders in the fields of geochemistry, geophysics, planetary science, astrobiology, and astronomy,» said Weinberger. «So, our institution is perfectly placed to tackle this cross-disciplinary challenge.»

In the next decade as a new generation of telescopes come online, scientists will begin to search in earnest for biosignatures in the atmospheres of rocky exoplanets. But the colleagues say that these observations must be put in the context of a larger understanding of how a planet’s total makeup and interior geochemistry determines the evolution of a stable and temperate surface where life could perhaps arise and thrive.

«The heart of habitability is in planetary interiors,» concluded Cody.

Source: Carnegie Institution for Science [May 02, 2019]



An evolutionary rescue in polluted waters

The combination of a big population, good genes and luck helps explain how a species of fish in Texas’ Houston Ship Channel was able to adapt to what normally would be lethal levels of toxins for most other species, according to a study to be published in the journal Science.

An evolutionary rescue in polluted waters
Atlantic killifish contributed key adaptive genetic variation to the Gulf killifish, which amounted
to an evolutionary rescue from toxic pollutants [Credit: Andrew Whitehead/UC Davis]

The exceptional survivor story of the Gulf killifish was one scientists at the University of California, Davis, Baylor University and their co-authoring colleagues wanted to unveil so they could learn more about what other species may need to adapt to drastically changed environments.

The minnow-like Gulf killifish are an important part of the food web for a number of larger fish species in coastal marsh habitats.

«Most species don’t survive radically altered environments,» said corresponding author Andrew Whitehead, a UC Davis professor of environmental toxicology. «By studying the survivors, we get insight into what it takes to be successful. In the case of the killifish, it came down to huge population sizes and luck.»

The researchers sequenced the genomes of hundreds of Gulf killifish living across a spectrum of toxicity — from clean water, moderately polluted water and very polluted water. They were searching for the footprints of natural selection that allowed the species to rapidly transition from a fish that is highly sensitive to pollution to one extremely resistant to it.

They were surprised to find that the adaptive DNA that rescued this Gulf Coast species came from an Atlantic Coast species of killifish, which has also been known to rapidly evolve high levels of pollution resistance. But Atlantic Coast killifish live at least 1,500 miles from their Houston brethren, leaving researchers to think their transport to the Gulf was likely an accident initiated by humans.

An evolutionary rescue in polluted waters
Embryos from resistant (left) and sensitive (right) populations of Gulf killifish dosed at the same concentration
of industrial contaminants. Resistant population embryo develops a normal, two chambered, heart with
proper blood flow, while sensitive embryo develops a string heart with no blood flow. Right embryo
 is unlikely to survive to hatch [Credit: Elias Oziolor/UC Davis]

Nonnative species can wreak environmental havoc on native species and habitats. But in this case, their arrival in the 1970s — right at a moment when Gulf killifish were likely beginning to decline — amounted to an «evolutionary rescue» from pollution for the Gulf killifish.

«While the vast majority of research on invasive species rightly focuses on the environmental damage they can cause, this research shows that under rare circumstances they can also contribute valuable genetic variation to a closely related native species, thus acting as a mechanism of evolutionary rescue,» said co-corresponding author Cole Matson, an associate professor at Baylor University.

Gulf killifish began with many advantages other species do not have. Species with large populations can harbor high levels of genetic diversity that can help them adapt to rapid change. Gulf killifish already had among the highest levels of genetic diversity of any species with a backbone.

Then, at the moment its population was beginning to decline, a long-distant relative — the Atlantic Coast killifish — came to visit, was able to successfully mate, and injected the Gulf species with genetic resources that helped it develop resilience and resistance to toxins. Whitehead is quick to note that not all species are so lucky.

«The adaptation of these killifish is a cautionary tale,» Whitehead said. «It tells us what we need to do better for the vast majority of species that don’t have access to the kind of genetic resources killifish have. If we care about preserving biodiversity, we can’t expect evolution to be the solution. We need to reduce how much and how quickly we’re changing the environment so that species can keep up.»

Humans are not only radically changing the environment, we are also fragmenting it, making it harder for animals to move throughout their range. Whitehead said a key lesson from killifish is the importance of keeping the doors to genetic diversity open. This includes connecting and preserving landscapes to allow for genetic variation to move more freely and naturally. That could help set the stage for more evolutionary «rescues» in the rapidly changing future.

Author: Kat Kerlin | Source: University of California — Davis [May 02, 2019]



New genome map sheds light on ancestry, diversity of today’s peanuts

Working to understand the genetics of peanut disease resistance and yield, researchers led by scientists at the University of Georgia have uncovered the peanut’s unlikely and complicated evolution.

New genome map sheds light on ancestry, diversity of today's peanuts
While Americans are familiar with one or two varieties of peanut, farmers in other parts of the world have been
 able to develop hundreds of varieties thanks to the peanut’s natural ability to shuffle its two distinct
subgenomes to produce new traits. These are some of the peanuts grown by the Caiabí people
who live on the Ilha Grande, Mato Grosso, Brazil. Peanut is very important for them
and they cultivate diverse types, each one with its use, name and story
[Credit: Fábio de Oliveira Freitas]

Researchers working as part of the International Peanut Genome Initiative have previously pinpointed one of the peanut’s two wild ancestors and shown that the peanut is a living legacy of some of the earliest human agricultural societies in South America. Since then the team has mapped the entire peanut genome and identified the crop’s second wild ancestor and the novel mechanism by which the shy, seed-hoarding plant generated the diversity we see today.

«Because of its complex genetic structure sequencing peanut was only possible using very recent developments in sequencing technology. The result is of unprecedented quality, and provides a reference framework for breeding and improvement of the peanut crop, and a whole new set of insights into the extraordinary genetic structure of peanut» said David Bertioli, Georgia Research Alliance Distinguished Investigator and peanut researcher at the College of Agricultural and Environmental Sciences.

Bertioli conducts his research through the CAES Institute for Plant Breeding, Genetics and Genomics, which is home to some of the world’s foremost experts in this area of crop science and has been prolific in providing new genomic tools and information to help plant breeders around the world develop more sustainable, productive crop varieties.

The team’s most recent paper was published in the journal Nature Genetics and is available online.

According to the USDA, farmers around the world grow 44.9 million metric tons of peanuts on more than 64 million acres. The crop is a staple food in many parts of Africa and Asia and is a source of peanut butter, snacks and cooking oil in the United States. In Georgia alone farmers grow $825 million in peanuts each year.

Despite their importance as a crop, plant researchers haven’t had many of the genetic tools needed to speed the introduction of more sustainable and productive peanut varieties. That was because, until recently, scientists had been unable to map the peanuts’ hypercomplex tetraploid genome. The Peanut Genome Initiative’s international collaboration and advancements in technologies and data processing yielded the breakthroughs.

Peanut genome sequenced

The bedrock of the team’s discoveries was the sequencing of the genome. Because the peanut originated from the hybridization of two wild ancestral species thousands of years ago, the initial phases of the project involved researchers developing genome sequences for those ancestors. Together, the ancestral genomes made a prototype for the genetic structure of cultivated peanuts. This was published in 2016.

This month, the Peanut Genome Initiative discusses the entire genome sequence for the modern cultivated peanut in a paper published in Nature Genetics on May 1.

The researchers used new advances in DNA-sequencing technologies to produce a complete genome sequence of unprecedented quality. The sequence consists of more than 2.5 billion base pairs of DNA arranged in 20 pairs of chromosomes, 10 pairs from each of the ancestral species.

The information in the sequence sheds light on parts of the plant’s genetic code that control traits like seed size and disease resistance, which are important to plant breeders. But the sequence also revealed more about the origin of peanut during the dawn of agriculture in South America and on the genetic mechanisms that have generated diversity and allowed adaptation to environments around the globe.

The mother of peanut

Using the new genome sequence as a framework, the team was able to analyze the variations in more than 200 of the most diverse peanuts from all of over the world. Researchers found characteristic genetic fingerprints shared by all the peanut plants tested, providing new evidence that all modern peanut varieties stem from the same original hybrid.

«The new study underlines how peanut’s origin was due to very special circumstances thousands of years ago. Ancient farmers transported one species into the range of another, allowing their hybridization and the formation of a new crop species,» said Soraya Leal-Bertioli, a senior research scientist with the UGA Institute of Plant Breeding, Genetics and Genomics and the CAES department of plant pathology.

Scientists with the initiative had previously found the male donor of the original hybrid and origin of peanut’s «B» subgenome. In this new study they identified the female donor, tracking the population of wild ancestral peanut that contributed the peanut «A» subgenome in Rio Seco, Argentina. These individuals form the «mother» population of peanut.

But the evidence that all modern peanuts can be traced to a single original hybrid sets up another mystery, Leal-Bertioli said. How does a plant with such a narrow genetic base develop so many variations and varieties?

«Shuffling, shuffling»

Most flowering plant species rely on animals or weather to spread their pollen or seeds to other plants to generate genetic diversity. Pollen and seeds can travel for miles, spreading newly occurring traits to new populations.

But peanuts, which produce their seeds underground, don’t do that. It took early human farmers and their long-distance transport of seeds to get the first two ancestral peanut parents together.

Since then, however, the plant has used a new mechanism for creating diversity.

The peanut has two sets of chromosomes, one from each ancestor. By analyzing more than 200 cultivated peanuts from all over the world, it was shown that different landraces and cultivars have shuffled the genetic material of the ancestors and deleted some sections altogether. Over the past the 10,000 years, this shuffling has happened thousands of times — allowing a much faster-paced generation of diversity than if the plants simply relied on mutation.

In a greenhouse on the UGA campus, the Bertiolis have worked with hybrids that re-create the original ancestral peanut and observed the shuffling in real time. They documented its effects in the spontaneous appearance of different flower colors. These same genetic mechanisms generate other types of variation as well, said David Bertioli.

The phenomenon explains the tremendous about of diversity seen in peanuts today, said Leal-Bertioli.

Author: J. Merritt Melancon | Source: University of Georgia [May 02, 2019]



A genomic tour-de-force reveals the last 5,000 years of horse history

Each year on the first Saturday in May, Thoroughbred horses reach speeds of over 40 miles per hour as they compete to win the Kentucky Derby. But the domestic horse wasn’t always bred for speed. In fact, an international team now has evidence to suggest that the modern horse is genetically quite different from the horses of even just a few hundred years ago.

A genomic tour-de-force reveals the last 5,000 years of horse history
This image shows a herd of Kazakh horses in the Pavlodar region of Kazakhstan in August 2016
[Credit: Ludovic Orlando]

Their work, appearing in the journal Cell, constructs the genetic history of the domestic horse across the world over the last 5,000 years by using the largest genome collection ever generated for a non-human organism. The findings identify two new horse lineages that are now extinct and suggest that familiar traits such as speed were only selected for more recently in their history.

«The horse has impacted human history like no other animal,» says Ludovic Orlando, a research director with CNRS and the University of Toulouse and a Professor of Molecular Archaeology at the University of Copenhagen. «If you look at the historical record from the Bronze Age onward, horses are always part of the equation up until very recent times, connecting civilizations and impacting transportation, warfare, and agriculture. Our goal was to understand how humans and their activities transformed the horse throughout history to fit their purposes—and how these changes in biology influenced human history.»

The team responsible for this project consisted of 121 collaborators, including geneticists, archaeologists, and evolutionary biologists from 85 institutions around the world, and examined genome-scale data from 278 horse specimens from across Eurasia over the last 42,000 years.

«Such a large collection of data means that we can build a much more precise understanding of horse domestication and management through space and time,» Orlando says. «But it was truly an interdisciplinary effort because of course it takes a lot more than just DNA to understand such a story. We had to integrate all these social, historical, and geographical aspects.»

A genomic tour-de-force reveals the last 5,000 years of horse history
This graphical abstract summarizes horse genetic history over the last 5,000 years
[Credit: Fages et al. 2019]

Overall, the team’s findings suggest that equine history was much more complex than was previously realized. Today, there are only two known lineages of horses, the domestic horse and the Przewalski’s horse. But the researchers here identified two additional now-extinct lineages of horses, one from the Iberian Peninsula and one from Siberia, both of which still existed 4,000-4,500 years ago.

«We found two lineages of horses at the far ends of Eurasia that are not related to what we call the domestic horse today, nor to the Przewalski’s horse. They are a sort of horse equivalent of what Neanderthals are to modern humans,» Orlando says.

The researchers also found a major shift in the genetic makeup of horses in Europe and Central Asia in the 7th to 9th centuries and say this shift probably corresponds to Islamic expansions. The horses common in Europe before that time are now only found in regions such as Iceland; the new European horses after that time were much more similar to horses found in Persia during the Sassanid Empire. When the team performed a scan to identify genes that had been selected for in these Persian horses, they found evidence of selection in genes associated with body shape.

«It was a moment in history that reshaped the landscape of horses in Europe. If you look at what we today call Arabian horses, you know that they have a different shape—and we know how popular this anatomy has been throughout history, including in racing horses. Based on the genomic evidence, we propose that this horse was so successful and influential because it brought a new anatomy and perhaps other favorable traits,» he says.

A genomic tour-de-force reveals the last 5,000 years of horse history
This map shows the locations of the archaeological sites where horse remains were found
[Credit: Fages et al. 2019]

The researchers found that there have been additional significant and recent changes in the domestic horse. Similar selection scans indicate that only in the last 1,500 years did traits such as ambling and speed over short distances become more actively sought. And when they looked at the overall genetic diversity of the domestic horse, the researchers found a sharp decline in the last 200 to 300 years. They believe this decline corresponds with new breeding practices that were introduced with the rise of the concept of «pure» breeds.

«What we picture as a horse today and what we picture as a horse from a thousand years ago or two thousand years ago was likely actually very different. Some of those traits that we are most familiar with are only a modern invention, and in the last few hundred years, we have actually impacted the horse genome a lot more than in the previous 4,000 years of domestication,» says Orlando.

He believes that this research can tell us a lot about both the past and the present. «Our findings show that the past is a lot more diverse than we thought it was and that it cannot be imagined or inferred through modern-day variation. But ancient DNA tells us a lot about today as well, because it teaches us about the consequences of some shifts in breeding practices,» he says. And that, he believes, can also affect the way we think about conservation and modern agricultural practices.

Of course, our understanding of the domestic horse’s history is far from complete. Orlando acknowledges that there are geographic and temporal gaps in his story. Perhaps mostly glaringly, we still don’t know when and or where the horse was domesticated. «Horse domestication is central to human history, and in 2019, we still don’t understand where it started. That’s mind-blowing,» he says.

He looks forward to filling in those blanks. «Whenever I’m asked about what finding I’m most excited about, I always say, the next one. Because this research opens the door for so many possibilities to be studied now.»

Source: Cell Press [May 02, 2019]



Archaeologists find 10th century settlement under former parking site in Brussels

The Brussels regional government has approved a request to prolong archaeological works currently taking place on the site of the former Parking 58 in the city centre, now the planned location for a new administrative centre for Brussels-City municipality.

Archaeologists find 10th century settlement under former parking site in Brussels
Credit: Baert Marc

The works are at the moment a gigantic hole in the ground where once there was a parking garage famous for the view from its top floor. When the multi-storey car park was razed, a routine architectural inspection uncovered some interesting artefacts, and construction was halted for further investigation, as the law allows.
The dig has now turned up evidence of a settlement on the banks of the Senne, the river on which Brussels grew up, with objects first thought to date to the 10th century, but which may in fact be up to three centuries older.

The replacement for the car park is a mammoth project to rehouse many of the city’s administrative offices from the building on nearby Boulevard Anspach by Place De Brouckère, but despite the fact that works have been at a standstill since last winter, archaeologists from the region’s heritage department asked for an extension, which has now been granted, Brussels minister-president Rudi Vervoort announced.

Archaeologists find 10th century settlement under former parking site in Brussels
Credit: Bruxelles Patrimoines

The finds made so far, in the centre of the site to a depth of some 7.5m, have been described as “spectacular” and “of crucial importance for the history of Brussels”. Among them: a stone quay on what was the bank of the Senne dating to the Middle Ages, wooden structures even older, and tools and materials such s leather shoes and wooden combs relating to various crafts practised back to possibly the seventh century, suggesting life was taking place on the site of what is now the city centre as many as 1400 years ago. When Islam was being founded, Cædmon was the earliest known poet in English and the population of the entire world was around 208 million, about the same as present-day Brazil.
As well as the typical finds of archaeological sites, such as tools and pottery, the extended investigation will allow microscopic examination of the soil in each level of the ground, giving a deeper insight into the conditions of life as the centuries passed.

“This excavation offers the possibility to write a chapter of the economic and social history of Brussels, for a period when the potential for archaeological research has mainly concentrated on religious sites and those related to the dominant elite of a city,” Vervoort said in a statement.

Author: Alan Hope | Source: The Brussels Times [May 03, 2019]



Explaining the exceptional economic resilience of the Carthaginians during the Punic Wars

Through two recent scientific publications in the journals Proceedings of the National Academy of Sciences and Quaternary International, Belgian researchers from the University of Liège and French, Tunisian and English researchers, provide unpublished and essential information to understand the exceptional economic resilience of the Carthaginians during the Punic wars.

Explaining the exceptional economic resilience of the Carthaginians during the Punic Wars
View of the archaeological site of Utica 
[Credit: © Elisa Pleuger]

The analysis of a series of deep cores taken from the Medjerda delta around the city of Utica shows the continued exploitation of former lead and silver mines in the Carthaginian hinterland during periods of conflict, these mining resources allowing Carthage to pay war compensation and finance armies despite the loss of its traditional sources of money in the Mediterranean.

The Punic Wars (264-146 BC) have been the subject of numerous studies focusing on the most sensational aspects of the conflict between Rome and Carthaginian civilization for the domination of the western Mediterranean, but few have addressed this paradox: the economic resilience of Carthage despite successive defeats, the loss of mining territories and the imposition of war reparations.

To explain this paradox, researchers have used geoarchaeological methods to solve an archaeological and historical problem. The researchers drilled cores between 15 and 24 metres deep in the Medjerda delta around the city of Utica, which, according to literary tradition, was one of the first three Phoenician foundations in the western Mediterranean around 1100 BC.

Utica was an important trading city located on a promontory facing the sea. Over the centuries, it has lost its access to the sea and its ports have been overwhelmed by the activity of the Medjerda wadi, which flows south of the city. Despite more than a century of investigations by archaeologists and associated researchers, the location of the city’s Phoenician and Roman ports remains unknown, buried under sediments resulting from the progradation of the Medjerda.

Explaining the exceptional economic resilience of the Carthaginians during the Punic Wars
Portion of the core cleaned for study and sampling 
[Credit: © Elisa Pleuger]

The cores have made it possible to go back to the 6th millennium BC (radiocarbon dating) and to characterize the different sedimentary layers, in particular by means of mineralogical and geochemical analyses. The use of a recently developed tracer in geoarchaeology, that of lead isotopes applied to the study of paleo-pollutions, has provided particularly important data for the chemical characterization of the different layers.

The results highlight the existence of a long seafront north of the promontory of Utica during the Phoenician and Roman periods. A deep marine environment is documented in the ancient bay in the 6th millennium BC and the depth of the water column along the northern facade was still 2 metres around the 4th — 3rd century BC. Another coring east of the Kalaat El Andalous promontory showed the possibility that this area was a protected port during the Phoenician and Roman periods.

At the same time, the data provide evidence of former lead and silver mines in the Carthaginian hinterland and present an operating chronology that appears to follow the main periods of geopolitical instability of the time. The first phase of mining activity recorded in the sediments of Utica took place during the Greek-Punic wars (480-307 BC), then during the Punic wars (264-146 BC).

During the Punic Wars, data suggest that Carthage was still able to pay compensation and finance armies despite the loss of its traditional sources of money in the Mediterranean. Research shows that the exploitation of Tunisian metal ores between the second half of the fourth century and the beginning of the third century BC contributed to the emergence of the Punic currency and the development of the Carthaginian economy.

Explaining the exceptional economic resilience of the Carthaginians during the Punic Wars
View of the archaeological site in the Medjerda delta 
[Credit: © Elisa Pleuger]

These scientific articles are a remarkable illustration of the contribution of geoarchaeology to the understanding of the interactions between a society and its environment over the course of history.

Source: Université de Liège [May 03, 2019]



Divine symbols and adored pets in ancient Greece

From cats and dogs to singing insects and drunken parrots, the ancient Greeks and Romans shared a deep and intimate connection with the animal kingdom.

Divine symbols and adored pets in ancient Greece
A boy and his dog, late 1st c. BC/early 1st cent. AD
[Credit: National Archaeological Museum]

Rabbits, dogs, snakes and birds… Everywhere we look in the archaeological and literary records of the classical world, it seems we find animals of almost every variety. Clearly, animals in ancient times featured commonly in people’s daily experiences, in popular storytelling and in mythological beliefs; their likenesses appear in vase paintings, frescoes, mosaics, stone sculptures and ceramic figurines, as well as on utilitarian or decorative objects of intricately carved ivory or hammered gold. Living in an age prior to mechanization, much of the ancient Greek and Roman populations resided in rural areas outside cities, so they had more regular contact and firsthand familiarity with animals than most of us do today.

Even in urban settings, humans and their animals tended to share space and live more closely together than we might find comfortable today. Livestock, including calves, sheep, goats and pigs, were used for pious sacrifices. Lions, tigers, bears and other wild creatures became the focus of popular and elite entertainment; either hunted in nature or captured and pitted against each other – or human combatants – in bloody arena contests.

Horses and other draft or pack animals labored on farms, but in wartime they were called up for duty on the battlefield, occasionally serving alongside elephants. At all levels of society, animals played key roles in public, religious and military life. However, it’s plain to see in ancient art and literature that the closest bond was felt in the home, between masters or mistresses and their beloved domestic pets.

Most denizens of the ancient world loved and appreciated their animal companions, even mourning them and erecting commemorative markers over their graves when they died. Aristotle, the first philosopher to undertake the formal study and classification of animals, viewed them as irrational creatures of lesser moral rank, placed on Earth solely to serve people. Other thinkers had greater esteem for them, including Pythagoras, who suggested animals possessed the reincarnated souls of human beings, after reportedly having witnessed the beating of a yelping puppy.

Household companions

Within the home and garden, the range of animals kept as pets was almost boundless, including dogs, ducks, geese, caged birds, rabbits, hares, tortoises, goats, quail and mice. Snakes had chthonic (underworld), spiritual significance, but were also employed – along with cats, ferrets or weasels – to keep rodents at bay. Chirping insects were treated like songbirds, with children weaving small boxes from reeds or slender branches to accommodate their pet locusts, crickets and cicadas.

Boys seeking amusement are reported by a scholar writing on Aristophanes’ “Wasps” to have caught large beetles and tethered them with a thread tied to one leg – a practice also seen in red-figure vase paintings. Other unusual pets included apes and monkeys (often taught to perform tricks), fawns and adult deer, gazelle, foxes and small mountain cats. Domesticated cats only became widespread during Roman times, perhaps due to increasing trade with Egypt.

Religious reverence may have played a part in the selection of pets, as certain animals were symbolic of a particular god or goddess. Sacred to Apollo and Artemis, for example, was the quail (ortyx) – likely a common sight at the divine twins’ central-Cycladic sanctuary on Delos, originally known as Ortygia or “Quail Island.” Pindar (5th century BC) and later mythographers relate that Asterie, sister of Leto (who bore the twins on Delos), escaped from Zeus’ advances by transforming herself into a quail, dropping into the Aegean Sea, then rising again as an island.

Quails thus possessed a divine spirit and were coveted for their pleasing voices and colorful plumage. Far wilder pets are known from the Roman era, when the emperors Domitian and Caracalla kept lions in their palaces. Caracalla’s beloved companion, Acinaces, ate with him at table and slept in his master’s chamber. Valentinian I had his servants take precious care of two she-bears, Mica Aurea (Gold Flake) and Innocentia (Innocence), to whom he apparently handed over his enemies as playthings.

Raising the alarm

Household security was always a concern in antiquity. Canines were common gatekeepers – as mosaic thresholds in Pompeii reveal with their inscriptions “Cave canem” (Beware of the dog). Geese, a favorite pet of Penelope, could similarly serve a protective purpose. Caged birds, too, might alert homeowners to visitors, but were more often kept for their cheerful chirping.

Talking green parrots, popular in Rome’s affluent homes, are described by Pliny as imports from India and “especially frolicsome under the influence of wine.” Even more ostentatious and expensive were pet peacocks, ridiculed alike by Greek comedic playwrights and Roman moralists.

A faithful friend

Above all, pets provided comforting companionship, best displayed by the loyal dog. Ancient Greece’s most illustrious hound was probably faithful Argos, who patiently awaited Odysseus’ return from Troy, and then, after their reunion, died contentedly. Among valued canine breeds were Molossian, Laconian and Cretan guard dogs and the ubiquitous Melitan lap dog from Malta.

The swineherd Eumaeus likely kept Molossians, as did nouveau riche Trimalchio, whose enormous beast Scylax, according to the Roman writer Petronius, caused a furious fracas during a banquet – attacking a smaller dog, upsetting a table lamp, smashing all the wine cups and sprinkling the guests with hot oil. Less ferocious was Publius’ little Issa, extolled by Martial: “More pure than the kiss of a dove… more loving than any maiden… dearer than Indian gems… She lies reclined upon his neck, and sleeps… and has never sullied the coverlet with a single spot…”

Author: John Leonard | Source: Kathimerini [May 03, 2019]



Blue whale fossil found in Italy is largest skeleton ever discovered

Researchers digging around in southern Italy’s Lake San Giuliana recently found something awesome: the largest-ever fossilized whale skeleton. The whale, when it was swimming around, was staggeringly big for the time. Measuring in at 85 feet in length, the whale would have weighed somewhere between 130 and 150 tons. That puts it officially in the books as the largest extinct animal ever found.

Blue whale fossil found in Italy is largest skeleton ever discovered
New whale fossils from Italy and Peru imply an early origin of modern mysticete gigantism. (a) Map of Italy showing
the fossil locality of Balaenoptera cf. musculus. (b) Cranium of Balaenoptera cf. musculus, in dorsal view. (c) Right
tympanic bulla of B. musculus (National Museum of Nature and Science specimen M25900), in dorsal view (i), and B.
 cf. musculus in dorsal (ii) and ventrolateral (iii) view. (d) Support surface for the mode shift model from Slater et al.;
 dark and light grey bars denote the range of the 2- and 3-unit support regions, respectively. (e) Support surface for
 the mode shift model with B. musculus truncated at 1.37 Ma, but with the Peruvian fossils excluded. (f) Mysticete
 body length plotted against time, and compared with the 80 (white), 90 (grey) and 95% (black) quantiles of 1000 BM
simulations on the baleen whale phylogeny of [4]; grey circles are chaeomysticetes, triangles toothed mysticetes,
and red circles the new fossils from Italy and Peru. Note that the BM simulations were carried out on a phylogeny
that did not include the specimens described here; their placement relative to the quantiles is thus merely indicative.
(d–f) Modified from Slater et al. Photo in (b) by Akhet s.r.l. (akhet.it). Drawing of B. musculus by Carl Buell
 [Credit: Giovanni Bianucci et al. 2019]

The bones are about 1.5 million years old and the skull tells scientists that it was a blue whale. It took the team nearly two years to collect the bones. In 2006, a farmer noticed a set of enormous vertebrae lodged in the clay on the shore of the lake. For the next two years, an Italian paleontologist named Giovanni Bianucci and his team dug out the remains. Since the farmer who had originally spotted the vertebrae used the lake to irrigate his fields, they dropped the water levels of the lake enough to excavate only in the fall, when the farmer’s harvest wouldn’t be affected.
The largest blue whales on record today are a hair bigger, reaching lengths of up to a hundred feet, but what is surprising to researchers is the fact that whales as big as the one found in Italy were so… BIG.

“The fact that such a large whale existed that long ago suggests that large whales had been around for quite a while,” says study coauthor Felix Marx, a paleontologist at the Royal Belgian Institute of Natural Sciences in Brussels, to National Geographic. “I don’t think species can evolve to such a size overnight.”

For years now, scientists have been struggling to figure out just how blue whales turned into the behemoths that they are today. Thanks to a few ice ages in during the early Pleistocene, vast amounts of water froze into ice, dropping sea levels. The whales that died way back then are now buried dozens of feet below sea level, so they’re a little hard to get to.

Because of that lack of information, Bianucci’s find is causing quite the stir. It’s adding to speculation that whales took far longer to become the giants we know today than previously believed.

A few ago, back in 2017, a study looked at fossilized baleen whale species and found that they seemed to have gotten significantly larger over a relatively short period of time—probably some 300,000 years ago. When Marx stuck the new fossil into the mix “the most probable date was pushed back to 3.6 million years, and likely even further, possibly as far back as six million years.”

The discovery is published in Biology Letters.

Source: The Inertia [May 04, 2019]



Old Kingdom tombs discovered on Egypt’s Giza Plateau

Despite the current heat wave in Egypt, local and international journalists and photographers flocked to the Giza Plateau on Saturday to witness the announcement by Minister of Antiquities Khaled El-Enany of the discovery of an Old Kingdom cemetery.

Old Kingdom tombs discovered on Egypt's Giza Plateau
Credit: Egypt. Ministry of Antiquities

El-Enany said that the announcement of the most recent discoveries and archaeological projects by the ministry not only have a scientific and archaeological value but are also good promotion of Egypt, showing the world the country’s true image, its culture, or soft power.
Zahi Hawass, a former antiquities minster, was also in attendance, and expressed his happiness that he was invited to attend the announcement, as the area where the cemetery was found is very close to his heart because it neighbours the pyramid-builders’ cemetery, which he considers a very important site.

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau
Credit: Egypt. Ministry of Antiquities

“The discovery of the pyramid-builders’ cemetery shows to the whole world that the pyramids were not built by slaves, but that their builders built their own tombs beside their king’s,” he said.
He told Ahram Online that the discoveries that the ministry have been announcing are the best way to promote Egypt abroad, because the news enters homes worldwide through the international media.

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau
Credit: Egypt. Ministry of Antiquities

Mostafa Waziri, secretary-general of the Supreme Council of Antiquities and director of the Egyptian Archaeological Mission team that made the discovery of the Old Kingdom cemetery, told Ahram Online that the team discovered several tombs and burial shafts, with the oldest a limestone family tomb from the fifth dynasty (circa 2500 BC) which retains some inscriptions and artwork.
The tomb belongs to two people. The first is Behnui-Ka, whose name has not previously been found in the Giza Plateau. He has seven titles, among them the priest, the judge, the purifier of the kings Khafre, Userkaf and Niuserre; the priest of goddess Maat, and the elder judicial official in the court.

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau
Credit: Egypt. Ministry of Antiquities

The second tomb owner, Nwi Who, had five titles, among them the chief of the great state, the overseer of the new settlements, and the purifier of Khafre.
Many artefacts were discovered in the tomb; among the most significant is a fine limestone statue of one of the tomb’s owners, his wife and son.

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau

Old Kingdom tombs discovered on Egypt's Giza Plateau
Credit: Egypt. Ministry of Antiquities

Ashraf Mohi, director general of Giza Plateau, said that the cemetery was reused extensively during the Late Period (from the 8th century BC). Many Late Period wooden painted and decorated anthropoid coffins were discovered on site. Some of them have hieroglyphic inscriptions.

Many wooden and clay funerary masks were also found, some with colour.

Author: Nevine El-Aref | Source: Ahram Online [May 04, 2019]




https://t.co/hvL60wwELQ — XissUFOtoday Space (@xufospace) August 3, 2021 Жаждущий ежик наслаждается пресной водой после нескольких дней в о...