четверг, 2 мая 2019 г.

Bear`s paw bones found in 4,500-year-old burial in Poland

Archaeologists discovered bones of a bear`s paw in the grave, in which a man with a child was buried approx. 4,500 years ago. It is a surprise for archaeologists — carcasses of domesticated animals were usually placed in burials from that period. The discovery was made near Sandomierz.











Bear`s paw bones found in 4,500-year-old burial in Poland
Credit: Monika Bajka

In the excavated niche, archaeologists found the dismembered remains of two people — an adult man and a small child. Nearby, in a large hollow, on the bottom of which a fire had been burning, there were animal bones, including the bones of a bear`s paw.


The discovery was made accidentally a few years ago, when a resident of the village of Święcica discovered bones when digging a garage driveway on his property. Archaeologists were called in to examine the prehistoric burial.


In the course of the research, it was found that a large entrance cavity led to the niche proper and served as a place for performing rituals.


«The traces of such rituals include animal bones found in the cavity and traces of burning fire», says archaeologist Monika Bajka, who led the excavations in Święcica in 2012.


In recent months, specialists analysed the discovered bones.


«It turned out that at the bottom of the entrance cavity, before the funerary niche, there was a single cattle bone and an almost complete bear paw. The latter find is completely unique among the late Neolithic graves», says PhD student at the Institute of Archaeology of the University of Rzeszów, Elżbieta Sieradzka.


An osteological analysis was performed by Dr. Mirosława Zabilska-Kunek and Prof. Daniel Makowiecki.











Bear`s paw bones found in 4,500-year-old burial in Poland
Credit: Monika Bajka

Sieradzka adds that the remains of domesticated animals — mainly cattle and pigs — were usually placed in the graves from this period. «That is why the grave from Święcica provides new data on the rituals of the Neolithic communities», the archaeologist believes.


The bear`s paw bones were found anatomically arranged. According to the researcher, this indicates that they were not feast leftovers, but rather that the paw had been placed in the grave in its entirety.


«The bear`s paw could be an offering for the deceased», she speculates.


The burial comes from the period when writing was not known yet. Therefore, scientists are looking for answers to the question about the significance of placing a bear`s paw in a grave by analysing the customs of peoples who lived more than 100 years ago, for example in Scandinavia. There are known writings of ethnographers on this subject.


«There are many examples of the symbolic meaning of this part of the carcass. In southern Fennoscandia (currently part of Finland and Russia) people believed that fangs, claws, penile bones and bear paws had healing powers, protected cattle from predators and gave their owner the animal`s senses and strength», Sieradzka says. She adds that in Siberia, the function of deterring evil was attributed to amulets made from bear paws.


Among the finds in the grave in Święcica, there were also pig bones, including a jaw. During the late Neolithic period, in some areas, animals played an important role in funeral rituals. Pig jaws are considered one of the most common elements of grave offerings of those communities. Since this part of the carcass has no significant consumer value, researchers are convinced of its ritual significance.


Author: Szymon Zdziebłowski | Source: PAP — Science in Poland [April 26, 2019]



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Rare life-size stucco sculpture unearthed in India’s Suryapet district

Archaeologists in the Indian state of Telangana have unearthed a rare treasure in the form of a life-sized stucco sculpture from a Buddhist site at Phanigiri in Suryapet. It is the biggest stucco sculpture found in the country so far.











Rare life-size stucco sculpture unearthed in India's Suryapet district
Credit: Telangana Today

According to officials of department of heritage, the life-size figurine found in the excavations is thought to represent one of Bhodhisattva in Jathaka Chakra.
The stucco has been brought to Hyderabad for mending and conservation, and is currently being watched over at the department of heritage in Gunfoundry.


“The stucco is about 1.73 metres in height and 35 cm in width,” said Sunita Bhagwat, in-charge director, department of heritage. “This unique sculpture found in the excavations is the biggest and the most important, and a rare finding not just in Telangana but also in the country.”











Rare life-size stucco sculpture unearthed in India's Suryapet district
Credit: V. Srinivas Goud

“The stucco was found facing the ground on the north-eastern side of the Buddhist site at Phanigiri. We are currently taking measures to mend the sculpture and conserve it for future generations,” said Bhagwat.
Apart from the life-sized stucco, these excavations brought to light a Mahastupa, apsidal chaitya grihas, votive stupas, pillared congregation halls, viharas, platforms with staircases at various levels, sculptural panels with Brahmi inscriptions, belonging to Satavahana period from first century BC, continued with Mahayana till the end of Ikshuvaka period and others in third-fourth century AD.


The preliminary excavation at Phanigiri was started in 1941 by Khaja Muhammad Ahmad of archaeology department of the then erstwhile Hyderabad state, and it continued till 1944.



After that, he state Archaeology and Museums Department (department of heritage) conducted excavations again after six decades, between 2001 and 2010, and once in 2013-14.


This year, the excavations in the site are being conducted in collaboration with Deccan College of Archaeology, Pune, under the guidance of assistant professor Srikanth Ganveer as co-excavation director and Pagadam Nagaraju as excavation director. The excavations, which began on February 2, are scheduled to be conducted till May 15.


Source: The Times of India [April 30, 2019]



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Italian court condemns ‘exorbitant costs’ of Pompeii restoration

The aim of rebuilding Pompeii’s ancient amphitheatre in tuff and reinforced concrete was to allow a show to be performed there. A show with lights and a stage set, violins and an orchestra. But is this the way to “make the most” of a world treasure? By relegating concerns for its protection to second place? Not according to Italy’s Court of Auditors, whose ruling contains harsh criticism of Pompeii’s former commissioner Marcello Fiori, appointed some years ago by Sandro Bondi and the Berlusconi government to “relaunch” the archaeological site. The court also ordered him to pay damages of €400,000. Who knows if this will be enough to convince those who manage similar sites to finally stop giving priority to making money through shows rather than to safeguarding Italy’s vast historical heritage.











Italian court condemns 'exorbitant costs' of Pompeii restoration
The restored amphitheatre in Pompeii [Credit: Corriere Della Sera]

Pneumatic drills, concrete mixers and bulldozers


But let’s go back to the beginning. To be precise, to 25 May 2010, when the Corriere published a report by Alessandra Arachi: “The noise leaves no room for doubt: the pneumatic drills with their unmistakable deafening vibrations. But then you just have to climb over a small fence and it’s there in front of you; it’s hard to believe your eyes.


The pneumatic drills almost become a mere detail in the terrible construction site of the amphitheatre in Pompeii, invaded by concrete mixers, bob karts, bulldozers, cables, sanders …” In a place where work should be carried out carefully with chisels and trowels, “the workers move among the ruins like bulls in a china shop”.


The complaint


Shortly afterwards, the head of the archaeological watchdog Antonio Irlando wrote to the ministry to complain of “works referred to in official plans as ‘Restoration and arrangement of the theatres in Pompeii for performance purposes’, which have evidently distorted the site’s original state”, in particular that of the cavea, which if compared to previous photos, has clearly “been rebuilt from scratch using modern tufa bricks”. Not to mention thick profiles in reinforced concrete.


As if that were not enough, to accommodate the “première” in what had been the ancient theatre – fitted with removable wooden steps which were subsequently rebuilt in concrete – huge containers were placed behind the scenes to contain the equipment and dressing rooms of the orchestra directed by Riccardo Muti, invited for the inauguration.


This had all received official blessing as part of an agreement to “make the most of” Pompeii and to “transform the amphitheatre into the South’s very own Arena of Verona”. The project also involved Naples’s San Carlo theatre, where the commissioner was Salvo Nastasi, later criticised by Paolo Isotta for other renovations including the construction (“or should that be destruction?”) of a bar in the legendary Neapolitan theatre. “Temporary” is the word they used to describe those obscene metal containers in the heart of the archaeological area. Nine years have passed, and they’re still there.


Expenditure


So what was the final expenditure for the renovation of the theatre, which initially should have cost €449,882 plus VAT? The sentence just issued by the court of appeal puts it at €5,778,939. A fortune. To be added to other “paltry expenses” of the director’s period of management. Such as the €102,963 spent for a census of the site’s 55 stray dogs: €1.872 per animal. Or the €55,000 spent on an order to the Mastroberardino winery for a thousand bottles of the wine “Villa dei misteri”, found by the subsequent management in the warehouses. Or the €3,762 for the purchase of seeds from the Antica Erboristeria Pompeiana, perhaps to be planted in the ancient gardens …


What is certain is that the sentence, written by the judge Cristiana Rondoni and signed by her colleague Angelo Canale, takes exception to the procurement procedure used, “without the prior publication of a call for tenders”. This should be possible “only in unforeseen and unforeseeable circumstances”. The court also criticised the “abnormal use of the powers delegated” to the then commissioner to “set up an operation that the prosecutor’s office considers unnecessarily expensive for the state” and which “was seriously against the public interest”. And on “expenditure of over €1.5 million”, with “illegal ‘mark-ups’ amounting to over €700,000, corresponding to 44% of the cost of the goods and services supplied”. The list goes on and on.


The verdict


And so, overturning the previous verdict, which had acquitted the commissioner, the new ruling insists above all on what it means to “make the most of” a heritage site: “Making the most of an historical asset cannot mean merely ‘exploiting’ it for business purposes, nor must it mean altering in any way its physical characteristics or limiting its fruition by the public, seeing that artistic, and especially archaeological assets, which crystallize our history, are public assets par excellence.” This is especially the case if the “only logical explanation” for the exorbitant costs was “the commissioner’s desire to end his period of office in what was – and the term seems fitting – a spectacular way”.


Even worse, in order to keep to the programme and schedule he had set himself, and certain he would find sponsors, Fiori focused above all on the “technical specifications of the stage set”, neglecting his commitment “to ensure that the project was compatible with the need to protect the archaeological site”.


No respect for the rules


In order to speed things up, in the words of the ruling, “Fiori failed to respect any rules: those established in ordinances issued by the civil defence authority, rules on procurement, and legislation on cultural heritage. He also disregarded the concerns of the government commission, the general principles governing the use of public resources, and the rules of common sense…”


The payment


The final result was a court order for Pompeii’s former director “to pay damages of € 400,000”. Apart from being a nasty blow for Marcello Fiori – whom Silvio Berlusconi initially appointed after the disappointing result in the 2013 elections as the man to lay the foundations for rebuilding Forza Italia –, the sentence could mark a turning point on the issue of safeguarding our treasures. God knows how important it is to “make the most of” a treasure that belongs to us all. Precisely for this reason, however, that treasure must above all be respected.


Author: Simon Tanner | Source: Corriere Della Sera [April 30, 2019]



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Anchor dating to Spanish conquest found off Mexico’s Gulf coast

Archaeologists in Mexico announced Tuesday they have found a Spanish anchor off the Gulf coast of Veracruz that dates to around the time of the Spanish conquest.











Anchor dating to Spanish conquest found off Mexico's Gulf coast
INAH experts discover a 15th century European anchor in the waters of Villa Rica, in Veracruz
[Credit: Jonathan Kingston, Nat Geo Image Collection]

The anchor was found at a site north of the current city of Veracruz, near where Hernán Cortés intentionally sank 10 of his ships in 1519 to prevent his troops from deserting.
Cortés landed in Veracruz 500 years ago, in April 1519. By August 1521 he had defeated the Aztec empire.











Anchor dating to Spanish conquest found off Mexico's Gulf coast
Dr. Chris Horrell taking anchor measurements to make a plan and establish its typology
[Credit: Jonathan Kingston, Nat Geo Image Collection]











Anchor dating to Spanish conquest found off Mexico's Gulf coast
Dr. Horrell taking measurements of the anchor wood clamp
[Credit: Jonathan Kingston, Nat Geo Image Collection]

The National Institute of Anthropology and History said the anchor hasn’t been proven to be from Cortés’ ships, but the search for evidence continues.
Another Spanish expedition came to the area just after Cortés, so the anchor could have been from those ships.











Anchor dating to Spanish conquest found off Mexico's Gulf coast
Dr. Junco, Dr. Damour and Dr. Horrell taking a sample of the wood stock to send to the laboratory
[Credit: Jonathan Kingston, Nat Geo Image Collection]

The institute said Tuesday the anchor’s wooden crosspiece was still intact, which allowed it to be dated to a tree that grew between 1450 and 1530. The wood was identified as a type of oak that grows in northern Spain.


Mexico has struggled with how to mark the 500th anniversary of the conquest, which resulted in the death of a large part of the country’s pre-Hispanic population.


President Andrés Manuel López Obrador has demanded an apology from Spain for the conquest


Source: The Associated Press [April 30, 2019]



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First examples of Iberian prehistoric ‘imitation amber’ beads at gravesites

Prehistoric Iberians created «imitation amber» by repeatedly coating bead cores with tree resins, according to a study published in the open-access journal PLOS ONE by Carlos Odriozola from Universidad de Sevilla, Spain, and colleagues.











First examples of Iberian prehistoric 'imitation amber' beads at gravesites
Amber bead samples examined in the study
[Credit: Odriozola et al., 2019]

Many studies have confirmed the ornamental and symbolic importance of amber to European prehistoric peoples. This study is the first to discuss potential prehistoric Iberian «imitation amber» beads made using the application of repeated resinite coatings on top of a bead core.


The authors obtained beads from two prehistoric sites in Spain: two from a cave tomb at the La Molina site in Sevilla, dating from the 3rd millennium BC, and four from a burial site in Cova del Gegant near Barcelona, dating from the 2nd millennium BC. Using infrared spectroscopy, an electron microscope probe, x-ray diffraction, and spectroscopy, the authors were able to study the chemical composition and structure of all six bead cores and coatings.


The beads from Cova del Gegant had a mollusk shell core, covered by a multilayered coating made up of tree resins, most likely pine. The beads were covered by a calcium-containing white deposit, which likely precipitated post-burial from the bone tissue of buried individuals. The beads from La Molina were also composed of a core covered by an amber-like resin, as well as two topmost layers of cinnabar and calcite which probably coated the beads post-burial.


The authors speculate these coating technologies were used to imitate amber’s translucence, shine, and color, since during this prehistoric period, amber was relatively rare and highly in demand. However, both tomb sites contained other exotic materials such as ivory, gold and cinnabar, so it’s not clear why individuals able to obtain these rare goods would use amber alternatives. The authors speculate that, especially in the Cova del Gegant where «imitation amber» was found directly alongside true amber beads, unscrupulous traders may have substituted low-cost fake amber to cheat their buyers. The authors also suggest chemical analysis of apparent «amber» artifacts could prevent erroneous amber identification in future studies of such Iberian sites.


Source: Public Library of Science [May 01, 2019]



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Observing Gaia from Earth to improve its star maps


ESA — Gaia Mission patch.


2 May 2019


While ESA’s Gaia mission has been surveying more than one billion stars from space, astronomers have been regularly monitoring the satellite’s position in the sky with telescopes across the world, including the European Southern Observatory in Chile, to further refine Gaia’s orbit and ultimately improve the accuracy of its stellar census.


One year ago, the Gaia mission released its much-awaited second set of data, which included high-precision measurements – positions, distance indicators and proper motions – of more than one billion stars in our Milky Way galaxy.



Gaia among the stars

The catalogue, based on less than two years of observations and almost four years of data processing and analysis by a collaboration of about 450 scientists and software engineers, has enabled transformational studies in many fields of astronomy, generating more than 1000 scientific publications in the past twelve months.


Meanwhile in space, Gaia keeps scanning the sky and gathering data that is being crunched for future releases to achieve even higher precision on the position and motion of stars and enable ever deeper and more detailed studies into our place in the cosmos. But to reach the accuracy expected for Gaia’s final catalogue, it is crucial to pinpoint the position and motion of the satellite from Earth.


To this aim, the flight dynamics experts at ESA’s operations centre make use of a combination of techniques, from traditional radio tracking and ranging to simultaneous observing using two radio antennas – the so-called delta-DOR method.



Gaia scanning the sky

In a unique and novel approach for ESA, the ground-based tracking of Gaia also includes optical observations provided by a network of medium-size telescopes across the planet.


The European Southern Observatory’s (ESO) 2.6-metre VLT Survey Telescope (VST) in Chile records Gaia’s position in the sky for about 180 nights every year.


“This is an exciting ground-space collaboration, using one of ESO’s world-class telescopes to anchor the trailblazing observations of ESA’s billion star surveyor,” says Timo Prusti, Gaia project scientist at ESA.


“The VST is the perfect tool for picking out the motion of Gaia,” adds Ferdinando Patat, head of the ESO’s Observing Programmes Office. “Using one of ESO’s first-rate ground-based facilities to bolster cutting-edge space observations is a fine example of scientific cooperation.”


In addition, the two-metre Liverpool telescope located on La Palma, Canary Islands, Spain, and the Las Cumbres Optical Global Telescope Network, which operates two-metre telescopes in Australia and the US, have also been observing Gaia over the past five years as part of the Ground Based Optical Tracking (GBOT) campaign.



ESO’s VLT Survey Telescope

“Gaia observations require a special observing procedure,” explains Monika Petr-Gotzens, who has coordinated the execution of ESO’s observations of Gaia since 2013. “The spacecraft is what we call a ‘moving target’, as it is moving quickly relative to background stars – tracking Gaia is quite the challenge!”


In these images Gaia is a mere dot of light among the many stars that the satellite itself has been measuring, so painstaking calibration is needed to transform this body of observations into meaningful data that can be included in the determination of the satellite’s orbit.


This required using data from Gaia’s second release to identify the stars in each of the images collected over the past five years and calculate the satellite’s position in the sky with a precision of 20 milliarcseconds or better (one arcsecond is equivalent to the size of a Euro coin seen from a distance of about four kilometres).


“This is a challenging process: we are using Gaia’s measurements of the stars to calibrate the position of the Gaia spacecraft and ultimately improve its measurements of the stars,” explains Timo.



Gaia’s sky in colour

The ground-based observations also provide key information to improve the determination of Gaia’s velocity through space, which must be known to the precision of a few millimetres per second. This is necessary to correct for a phenomenon known as aberration of light – an apparent distortion in the direction of incoming light due to the relative motion between the source and an observer – in a way similar to tilting one’s umbrella while walking through the rain.


“After careful and lengthy data processing, we have now achieved the accuracy required for the ground-based observations of Gaia to be implemented as part of the orbit determination,” says Martin Altmann, lead of the GBOT campaign from the Astronomisches Rechen-Institut, Centre for Astronomy of Heidelberg University, Germany, who works in close collaboration with colleagues from the Paris Observatory in France.


The GBOT information will be used to improve our knowledge of Gaia’s orbit not only in observations to come, but also for all the data that have been gathered from Earth in the previous years, leading to improvements in the data products that will be included in future releases.


Notes for editors


ESA’s Gaia satellite was launched in 2013 to create the most precise three-dimensional map of one billion of the stars within the Milky Way. The mission has released two lots of data so far: Gaia Data Release 1 on 14 September 2016, and Gaia Data Release 2 on 25 April 2018 (the latter of which was used in this study). More releases will follow in coming years.


The European Southern Observatory (ESO) is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor.


The VLT Survey Telescope (VST) is currently the largest survey telescope observing the sky in visible light. This state-of-the-art 2.6-m telescope is located at ESO’s Paranal Observatory.


On 20 August 2015, the ESA and ESO Directors General signed a cooperation agreement between the two organisations.


In order to foster exchanges between astrophysics-related spaceborne missions and ground-based facilities, as well as between their respective communities, ESA and ESO are joining forces to organise a series of international astronomy meetings.


The first ESA-ESO joint workshop, with a focus on multi-messenger astronomy, will take place in November 2019 at ESO’s headquarters in Garching, Germany, and a call for proposals for the second workshop, to take place in 2020 at ESA’s astronomy centre near Madrid, Spain, is currently open.


Related links:


Gaia Data Release 1: http://www.esa.int/Our_Activities/Space_Science/Gaia/Gaia_s_billion-star_map_hints_at_treasures_to_come


Gaia Data Release 2: https://www.esa.int/Our_Activities/Space_Science/Gaia/Gaia_creates_richest_star_map_of_our_Galaxy_and_beyond


GBOT information: http://gaiainthesky.obspm.fr/index_gaia.php?page=FOV&sous_menu=public


First ESA-ESO joint workshop: http://www.eso.org/sci/meetings/2019/eso_esa_conference.html


European Southern Observatory’s (ESO): https://www.eso.org/


European Southern Observatory’s (ESO) release: https://www.eso.org/public/news/eso1908/?lang


VLT Survey Telescope (VST): https://www.eso.org/public/teles-instr/paranal-observatory/surveytelescopes/vst/


Gaia: http://www.esa.int/Our_Activities/Space_Science/Gaia


Images, Video, Text, Credits: ESA/Markus Bauer/Timo Prusti/ESO/Calum Turner/Astronomisches Rechen-Institut/Centre for Astronomy of Heidelberg University/Martin Altmann/ESO/Y. Beletsky; CC BY 4.0/ESA/Gaia/DPAC, CC BY-SA 3.0 IGO.


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2019 May 2 Manicouagan Impact Crater from Space Image Credit:…


2019 May 2


Manicouagan Impact Crater from Space
Image Credit: NASA, International Space Station Expedition 59


Explanation: Orbiting 400 kilometers above Quebec, Canada, planet Earth, the International Space Station Expedition 59 crew captured this snapshot of the broad St. Lawrence River and curiously circular Lake Manicouagan on April 11. Right of center, the ring-shaped lake is a modern reservoir within the eroded remnant of an ancient 100 kilometer diameter impact crater. The ancient crater is very conspicuous from orbit, a visible reminder that Earth is vulnerable to rocks from space. Over 200 million years old, the Manicouagan crater was likely caused by the impact of a rocky body about 5 kilometers in diameter. Currently, there is no known asteroid with a significant probability of impacting Earth in the next century. But a fictional scenario to help practice for an asteroid impact is on going at the 2019 IAA Planetary Defense Conference.


∞ Source: apod.nasa.gov/apod/ap190502.html


Staying Healthy Longer in Space


ISS — Biotechnology Facility patch.


May 1, 2019


Falling ill while traveling is an unfortunate yet common occurrence. Even a minor bug can ruin an entire trip. But for astronauts, getting sick on a long space voyage would have far more serious consequences than a little spoiled fun.


The Rodent Research 12 (RR-12) investigation joins a series of studies aboard the International Space Station with the common goal of keeping astronauts healthy in space.



Image above: Nina Nishiyama, Stephen Chapes, Trisha Rettig, and Claire Ward prepare preliminary work on the RR-12 investigation. Image Credit: Loma Linda University.


Research has shown that spaceflight causes significant changes in the human immune system. These changes seem to depend on the length of time spent in space, and more research is needed to confirm these findings and significance for long term health.


Scientists also want to know exactly how the immune system responds when exposed to a pathogen that can cause illness while in space. Mice have immune systems very similar to that of humans, so RR-12 is sending mice to the space station in an effort to answer that question.


“First, we are looking at the primary immune response, which will show how well the immune system produces antibodies the first time it sees an immune challenge,” said principal investigator Michael J. Pecaut at Loma Linda University in California. “Then, we look at how well the memory response works in space.” Pecaut leads the experiment with co-investigator Stephen K. Chapes at Kansas State University in Manhattan, Kansas.



Animation above: NASA astronaut Anne McClain works on setting up a Habitat Unit in the Life Sciences Glovebox for the Rodent Research 12 investigation. Animation Credit: NASA.


Because infectious organisms are unwelcome on the space station, the researchers are using a vaccine that is similar to the one commonly used for tetanus to generate an antibody or immune response in the mice. The vaccine toxoid poses no risk to crew members because all have already received the same vaccine.


One group of mice receives its first exposure to the vaccine after two weeks aboard the space station with researchers examining the number and type of antibodies produced as a result. This part of the study helps determine if the immune system can respond to a challenge it has never seen before while in space. The investigators expect to see fewer immune cells and different types of them than the vaccine typically triggers on the ground.


A second set of mice receives the vaccine on the ground so it can develop an antibody response and immunological memory before flying to the space station, just as a person would after receiving a vaccination. The mice receive a second vaccination two weeks into the flight. This allows researchers to test whether immunological memory is effective in space by comparing the responses in the two groups of mice.



Image above: NASA astronaut Anne McClain working with a Mouse Habitat Unit. McClain tweeted:“@ISS_Research is really phenomenal; every day we get to play a part in learning about our universe, our Earth, and the creatures that live on it. Getting to do science on the ceiling? Well, now that’s just cool!” Image Credit: NASA.


“If the diversity and number of immune cells that are produced changes in space, that affects the ability of astronauts to respond to some sort of immune challenge such as bacteria on the station,” Pecaut said.


The investigators plan to analyze the immune response of the mice in orbit so they can be sure the changes they see are caused by spaceflight and not by the experience of re-entry or return to Earth.


In addition to establishing a link between spaceflight and reduced immune system activation, the investigation could lead to measures that counteract the reduced activation to help protect crew members on long-duration missions.


The investigation also may advance research on antibody production and response to vaccines, helping to improve the effectiveness of vaccines and other therapies for treating diseases and cancers.


“Because NASA is so careful with its astronauts, very few people get sick during spaceflight and it’s not a major concern now,” Pecaut said. “But as we start sending astronauts on longer trips, or as opportunities for space commercialization or tourism ramp up, we need to know that the immune system is still effective. We want to be sure that astronauts can respond to an immune system challenge in space the same as on Earth.”



International Space Station (ISS), the space laboratory. Image Credit: NASA

After all, no one wants a trip to the Moon or Mars ruined by an illness.


This investigation, sponsored by NASA Space Life and Physical Science-Space Biology (NASA-SLPS-Space Biology), is the first time rodents have flown to the space station from NASA’s Wallops Flight Facility aboard a Cygnus spacecraft. This mission tests a new late load capability, allowing time-sensitive experiments to be loaded into Cygnus just 24 hours before launch rather than the previous four-day requirement.


Stay tuned with up-to-date information on Northrop Grumman’s 11th Commercial Resupply Mission (CRS-11) launch here: https://sites.wff.nasa.gov/wmsc/#/home


Related links:


Rodent Research 12 (RR-12): https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7868


NASA-SLPS-Space Biology: https://www.nasa.gov/spacebio


NASA’s Wallops Flight Facility: https://www.nasa.gov/centers/wallops/home


NASA’s Johnson Space Center (JSC): http://www.nasa.gov/centers/johnson/home/index.html


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


Images (mentioned), Text, Credits: NASA/Michael Johnson/JSC/International Space Station Program Science Office/Melissa Gaskill.


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6 Things You Didn’t Know About Our ‘First’ Space Flight Center


When NASA began operations on Oct. 1, 1958, we consisted mainly of the four laboratories of our predecessor, the National Advisory Committee for Aeronautics (NACA). Hot on the heels of NASA’s first day of business, we opened the Goddard Space Flight Center. Chartered May 1, 1959, and located in Greenbelt, Maryland, Goddard is home to one of the largest groups of scientists and engineers in the world. These people are building, testing and experimenting their way toward answering some of the universe’s most intriguing questions.


To celebrate 60 years of exploring, here are six ways Goddard shoots for the stars.


image

For the last 60 years, we’ve kept a close eye on our home planet, watching its atmosphere, lands and ocean.


Goddard instruments were crucial in tracking the hole in the ozone layer over Antarctica as it grew and eventually began to show signs of healing. Satellites and field campaigns track the changing height and extent of ice around the globe. Precipitation missions give us a global, near-real-time look at rain and snow everywhere on Earth. Researchers keep a record of the planet’s temperature, and Goddard supercomputer models consider how Earth will change with rising temperatures. From satellites in Earth’s orbit to field campaigns in the air and on the ground, Goddard is helping us understand our planet.


image

We seek to answer the big questions about our universe: Are we alone? How does the universe work? How did we get here?


We’re piecing together the story of our cosmos, from now all the way back to its start 13.7 billion years ago. Goddard missions have contributed to our understanding of the big bang and have shown us nurseries where stars are born and what happens when galaxies collide. Our ongoing census of planets far beyond our own solar system (several thousand known and counting!) is helping us hone in on which ones might be potentially habitable.


image

We study our dynamic Sun.


Our Sun is an active star, with occasional storms and a constant outflow of particles, radiation and magnetic fields that fill the solar system out far past the orbit of Neptune. Goddard scientists study the Sun and its activity with a host of satellites to understand how our star affects Earth, planets throughout the solar system and the nature of the very space our astronauts travel through.


image

We explore the planets, moons and small objects in the solar system and beyond. 


Goddard instruments (well over 100 in total!) have visited every planet in the solar system and continue on to new frontiers. What we’ve learned about the history of our solar system helps us piece together the mysteries of life: How did life in our solar system form and evolve? Can we find life elsewhere?


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Over 60 years, our communications networks have enabled hundreds of NASA spacecraft to “phone home.”


Today, Goddard communications networks bring down 98 percent of our spacecraft data – nearly 30 terabytes per day! This includes not only science data, but also key information related to spacecraft operations and astronaut health. Goddard is also leading the way in creating cutting-edge solutions like laser communications that will enable exploration – faster, better, safer – for generations to come. Pew pew!


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Exploring the unknown often means we must create new ways of exploring, new ways of knowing what we’re “seeing.” 


Goddard’s technologists and engineers must often invent tools, mechanisms and sensors to return information about our universe that we may not have even known to look for when the center was first commissioned.


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Behind every discovery is an amazing team of people, pushing the boundaries of humanity’s knowledge. Here’s to the ones who ask questions, find answers and ask questions some more!


Make sure to follow us on Tumblr for your regular dose of space: http://nasa.tumblr.com.


InSight Captures Sunrise and Sunset on Mars


NASA — InSight Mission patch.


May 1, 2019


NASA’s InSight lander captured a series of sunrise and sunset images.



Image above: NASA’s InSight lander used its Instrument Deployment Camera (IDC) on the spacecraft’s robotic arm to image this sunrise on Mars on April 24, 2019, the 145th Martian day (or sol) of the mission. This was taken around 5:30 a.m. Mars local time.Image Credits: NASA/JPL-Caltech.



Image above: NASA’s InSight lander used the Instrument Deployment Camera (IDC) on the end of its robotic arm to image this sunset on Mars. This color-corrected version more accurately shows the image as the human eye would see it. Image Credits: NASA/JPL-Caltech.


A camera on the spacecraft’s robotic arm snapped the photos on April 24 and 25, the 145th Martian day, or sol, of the mission. In local Mars time, the shots were taken starting around 5:30 a.m. and then again starting around 6:30 p.m. As a bonus, a camera under the lander’s deck also caught clouds drifting across the Martian sky at sunset.


These images are available as both «raw» and color-corrected versions. It’s easier to see some details in the raw versions, but the latter more accurately show the images as the human eye would see them. Much farther from Mars than it is from Earth, the Sun appears only about two-thirds the size that it does when viewed from Earth.



Image above: NASA’s InSight lander used the Instrument Deployment Camera (IDC) on the end of its robotic arm to image this sunset on Mars on April 25, 2019, the 145th Martian day, or sol, of the mission. This was taken around 6:30 p.m. Mars local time. Image Credits: NASA/JPL-Caltech.



Image above: NASA’s InSight lander used the Instrument Deployment Camera (IDC) on the end of its robotic arm to image this sunset on Mars. This color-corrected version more accurately shows the image as the human eye would see it. Image Credits: NASA/JPL-Caltech.


This is actually the second time InSight has captured these daily events: The camera took practice shots on March 2 and 10. «It’s been a tradition for Mars missions to capture sunrises and sunsets,» said Justin Maki, InSight science team co-investigator and imaging lead at NASA’s Jet Propulsion Laboratory in Pasadena, California. «With many of our primary imaging tasks complete, we decided to capture the sunrise and sunset as seen from another world.»


The first mission to send back such images was the Viking 1 lander, which captured a sunset on Aug. 21, 1976; Viking 2 captured a sunrise on June 14, 1978. Since then, both sunrises and sunsets have been recorded by the Spirit, Opportunity and Curiosity rovers, among other missions.



Animation above: NASA’s InSight used its Instrument Context Camera (ICC) beneath the lander’s deck to image these drifting clouds at sunset. This series of images was taken on April 25, 2019, the 145th Martian day, or sol, of the mission, starting at around 6:30 p.m. Mars local time. Animation Credits: NASA/JPL-Caltech.



Animation above: NASA’s InSight used its Instrument Context Camera (ICC) beneath the lander’s deck to image these drifting clouds at sunset. This color-corrected version more accurately shows the image as the human eye would see it. Animation Credits: NASA/JPL-Caltech.


About InSight


JPL manages InSight for NASA’s Science Mission Directorate. InSight is part of NASA’s Discovery Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama. Lockheed Martin Space in Denver built the InSight spacecraft, including its cruise stage and lander, and supports spacecraft operations for the mission.


A number of European partners, including France’s Centre National d’Études Spatiales (CNES) and the German Aerospace Center (DLR), are supporting the InSight mission. CNES provided the Seismic Experiment for Interior Structure (SEIS) instrument to NASA, with the principal investigator at IPGP (Institut de Physique du Globe de Paris). Significant contributions for SEIS came from IPGP; the Max Planck Institute for Solar System Research (MPS) in Germany; the Swiss Federal Institute of Technology (ETH Zurich) in Switzerland; Imperial College London and Oxford University in the United Kingdom; and JPL. DLR provided the Heat Flow and Physical Properties Package (HP3) instrument, with significant contributions from the Space Research Center (CBK) of the Polish Academy of Sciences and Astronika in Poland. Spain’s Centro de Astrobiología (CAB) supplied the temperature and wind sensors.


Related links:


Seismic Experiment for Interior Structure (SEIS): https://mars.nasa.gov/insight/mission/instruments/seis/


Heat Flow and Physical Properties Package (HP3): https://mars.nasa.gov/insight/mission/instruments/hp3/


For more about InSight, visit: https://mars.nasa.gov/insight/


Images (mentioned), Animations (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Andrew Good.


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NASA and Blue Origin Help Classrooms and Researchers Reach Space


NASA logo.


May 1, 2019


“We are now on the verge of giving students and teachers the ability to build and fly affordable experiments in space. When teachers are this excited about putting experiments in space, their students can’t help but get excited about space, too.”



Image above: As human explorers venture to the Moon and Mars, what are the biological and physiological effects they must contend with? Nanoracks is hoping to give researchers a new tool to answer that question with a new centrifuge designed for suborbital rockets like Blue Origin’s New Shepard. Image Credit: NASA.


Elizabeth Kennick, president of Teachers in Space, does not take the opportunity to fly an experiment to space for granted. The nonprofit organization has worked with educators and engineers to design and test standard equipment for classroom-developed experiments, including 3D-printed frames, customizable processors, power adaptors and more. The equipment first flew on high-altitude balloons and more recently on a stratospheric glider. Now, thanks to support from NASA’s Flight Opportunities program, the equipment will fly higher than ever before: to space on the next launch of Blue Origin’s New Shepard rocket.



Image above: A sustainable human presence on the Moon will require manufacturing materials and structures on the surface. Space-based 3D printing capabilities will be key to this endeavor. On the next Blue Origin launch, researchers from the University of Kentucky will test 3D printing techniques that could be the first to produce metal components in space. Image Credit: NASA.


Nine NASA-supported payloads are expected to ride on New Shepard, targeting liftoff from Blue Origin’s West Texas launch site no earlier than May 2 at 9:30 a.m. EDT. Blue Origin’s live launch webcast will air on NASA Television and the agency’s website.


“It’s such a huge milestone,” said Kennick. “This opens the door to flying more experiments for more schools, and that means exposing more teachers and students to the promise of spaceflight.”



Image above: Teachers in Space will fly a standardized framework for classroom-developed space experiments on Blue Origin’s next flight. Comprised of 3D-printed CubeSat frames, a standard set of customizable processors and a fireproof cabinet housing, the equipment will provide a turnkey solution for housing student- and teacher-developed payloads on future flights to space. Image Credit: Teachers in Space.


That promise is bolstered by Flight Opportunities, which lets researchers test technologies in a relevant environment—particularly innovations that will help NASA return to the Moon and send crewed missions to Mars.


The payloads will experience the rigors of a rocket launch and the challenges of a zero-gravity environment. These conditions will give researchers valuable insights into how their technologies would hold up on exploration missions.


A 3D printing experiment from the University of Kentucky could further advance in space manufacturing—a critical capability for long-term stays on the lunar surface. While there are 3D printers on the International Space Station, the university’s experiment, if successful, would provide the capability to manufacture metal components in space.



Image above: The nonprofit Teachers in Space aims to engage educators in spaceflight and inspire the next generation of space explorers along the way. Emily, Drucilla, and Jadalynn (left to right), students at New York’s Central Square Middle School, have developed a method of testing whether moss could survive a trip to the stratosphere, and flew it on a Perlan glider in El Calafate, Argentina. The equipment tested on Blue Origin’s upcoming flight will open the door to putting their moss experiment—and many others—in space. Here, the girls work on assembling a CubeSat frame, similar to one that will fly on New Shepard. Image Credits: Teachers in Space/Jim Kuhl.


Future explorers will need protection from potentially negative effects of deep space travel. With a new suborbital centrifuge from NanoRacks, researchers may be able to collect biological and physical data on suborbital rocket flights. A space-based centrifuge can simulate the gravity environment on the Moon or Mars. The capability could make it faster and cheaper to gather critical data.


Missions to the Moon and the Red Planet will also require advanced fuel gauging systems— giving accurate measurements of the amount of propellant onboard vehicles operating in deep space without the need for complex procedures. A propellant gauging experiment from Purdue University aims to do just that.



Blue Origin’s New Shepard reusable, suborbital rocket. launch. Image Credit: Blue Origin

The other Flight Opportunities—supported payloads aboard this launch are:


Evolved Medical Microgravity Suction Device


Orbital Medicine, Inc., Richmond, Virginia
This medical device could assist in treating space-based emergencies, such as a collapsed lung. It would collect blood in microgravity, allow lungs to continuously inflate, and store blood for transfusion.


Suborbital Flight Experiment Monitor-2


NASA’s Johnson Space Center, Houston
This instrumentation package is designed to characterize the flight environment (e.g., acceleration, acoustics, temperature, pressure, humidity) of suborbital vehicles that are candidates for testing new space technologies.


Flow Boiling in Microgap Coolers


NASA’s Goddard Space Flight Center, Greenbelt, Maryland
This thermal management technique addresses the limitations of current cooling methods for miniaturized devices and electronics needed for technology payloads on space-bound missions.


BioChip SubOrbitalLab


HNu Photonics, LLC, Kahului, Hawaii
This experiment aims to enable researchers to observe cell function in real time during flight, in order to understand how microgravity and space exposure effects human physiology—critical insights for long-duration missions.


Strata-S1


University of Central Florida, Orlando
This payload addresses the need for detailed understanding of the behavior of space dust, regolith and other particles on the surfaces of small bodies in space, to inform both robotic and human space exploration.


About Flight Opportunities


The Flight Opportunities program is funded by NASA’s Space Technology Mission Directorate at the agency’s Headquarters in Washington and managed at NASA’s Armstrong Flight Research Center in Edwards, California. NASA’s Ames Research Center in California’s Silicon Valley manages the solicitation and evaluation of technologies to be tested and demonstrated on commercial flight vehicles.


Standardized Stacks Provide Easy Payload Support



Image above: The Crew Capsule is designed to accommodate up to six payload stacks with as many as 36 individual Payload Lockers. Future flights will replace some of these stacks with seats to support human-tended payload flights, allowing researchers to conduct their own hands-on work in space. Image Credit: Blue Origin.


Blue Origin and other U.S. commercial spaceflight providers are contracted to provide flight services to NASA for flight testing and technology demonstration. Researchers from academia and industry with concepts for exploration, commercial space applications or other space utilization technologies of potential interest to NASA can receive grants from the Flight Opportunities program to purchase suborbital flights from these and other U.S. commercial spaceflight providers.


Related links:


NASA’s Flight Opportunities program: https://www.nasa.gov/directorates/spacetech/flightopportunities/index.html


NASA Television: https://www.nasa.gov/live


3D printing experiment: https://flightopportunities.nasa.gov/technologies/178/


Evolved Medical Microgravity Suction Device: https://flightopportunities.nasa.gov/technologies/162/


Suborbital Flight Experiment Monitor-2: https://flightopportunities.nasa.gov/technologies/168/


Flow Boiling in Microgap Coolers: https://flightopportunities.nasa.gov/technologies/173/


BioChip SubOrbitalLab: https://flightopportunities.nasa.gov/technologies/181/


Strata-S1: https://flightopportunities.nasa.gov/technologies/182/


NASA’s Space Technology Mission Directorate: https://www.nasa.gov/directorates/spacetech/home/index.html


NASA’s Armstrong Flight Research Center: https://www.nasa.gov/centers/armstrong/home/index.html


NASA’s Ames Research Center: https://www.nasa.gov/ames


Blue Origin: https://www.blueorigin.com/


Images (mentioned), Text, Credits: NASA/Loura Hall/Armstrong Flight Research Center, by Nicole Quenelle.


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Astronauts Relax Today Before Robotics Work and Dragon Cargo Mission


ISS — Expedition 59 Mission patch.


May 1, 2019


The Expedition 59 astronauts are off-duty today relaxing before the planned launch and capture of the SpaceX Dragon resupply ship this weekend. In Mission Control, robotics engineers are preparing to swap a failed power distributor outside the International Space Station.


On April 29, the space station team identified an issue with one of the station’s Main Bus Switching Units (MBSU) that distributes power to two of the eight power channels on the station.  There are no immediate concerns for the crew or the station. Flight controllers are scheduled to perform a series of maneuvers to robotically swap the failed MBSU for a spare on Wednesday, May 1 and Thursday, May 2. After the swap is complete, flight controllers will conduct a series of checkouts on the newly installed MBSU and take steps to return the station to full power capability to support SpaceX capture and berthing.



Image above: Astronauts David Saint-Jacques (foreground) and Nick Hague are pictured April 24 training to capture the SpaceX Dragon cargo craft on the robotics workstation inside the U.S. Destiny laboratory module. Image Credit: NASA.


CRS-17 Liftoff No Earlier Than Friday, May 3, at 3:11 EDT


NASA and SpaceX are pressing ahead to launch Dragon no earlier than Friday May 3 at 3:11 a.m. EDT to deliver nearly 5,500 pounds of science, supplies and hardware. Astronauts David Saint-Jacques and Nick Hague will be in the cupola Sunday to command the Canadarm2 robotic arm to capture Dragon around 7 a.m.



International Space Station (ISS). Animation Credit: NASA

Flight Engineers Anne McClain and Christina Koch will help unpack and activate the time critical experiments after Dragon is installed on the Harmony module. New lab mice will be quickly transferred and housed in specialized habitats for an immune system study. Fresh biological samples, such as kidney cells, will be also stowed in science freezers and incubators for later analysis.


Related links:


Expedition 59: https://www.nasa.gov/mission_pages/station/expeditions/expedition59/index.html


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


Canadarm2: https://www.nasa.gov/mission_pages/station/structure/elements/mobile-servicing-system.html


Immune system study: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7868


Kidney cells: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7819


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


Image (mentioned), Animation (mentioned), Text, Credits: NASA/Mark Garcia.


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Flowering plants, new teeth and no dinosaurs: New study sheds light on the rise of...

A new study published in the Proceedings of the National Academy of Sciences identified three factors critical in the rise of mammal communities since they first emerged during the Age of Dinosaurs: the rise of flowering plants, also known as angiosperms; the evolution of tribosphenic molars in mammals; and the extinction of non-avian dinosaurs, which reduced competition between mammals and other vertebrates in terrestrial ecosystems.











Flowering plants, new teeth and no dinosaurs: New study sheds light on the rise of mammals
Well-preserved fossils ― like this Yanoconodon allini (Specimen No.: NJU P06001; Formation: Yixian;
Age: 122.2–124.6 million years ago; Provenance: China) ― enabled the team to infer ecology
of these extinct mammal species and look at changes in mammal community structure during
the last 165 million years [Credit: Meng Chen]

Previously, mammals in the Age of Dinosaurs were thought to be a relatively small part of their ecosystems and considered to be small-bodied, nocturnal, ground-dwelling insectivores. According to this long-standing theory, it wasn’t until the K-Pg mass extinction event about 66 million years ago, which wiped out all non-avian dinosaurs, that mammals were then able to flourish and diversify. An astounding number of fossil discoveries over the past 30 years has challenged this theory, but most studies looked only at individual species and none has quantified community-scale patterns of the rise of mammals in the Mesozoic Era.
Co-authors are Meng Chen, a University of Washington alumnus and current postdoctoral researcher at Nanjing University; Caroline Strömberg, a University of Washington biology professor and curator of paleobotany at the UW’s Burke Museum of Natural History & Culture; and Gregory Wilson, a UW associate professor of biology and Burke Museum curator of vertebrate paleontology. The team created a Rubik’s Cube-like structure identifying 240 «eco-cells» representing possible ecological roles of mammals in a given ecospace. These 240 eco-cells cover a broad range of body size, dietary preferences, and ways of moving of small-bodied mammals. When a given mammal filled a certain type of role or eco-cell, it filled a spot in the ‘Rubik’s Cube.’ This method provides the first comprehensive analysis of evolutionary and ecological changes of fossil mammal communities before and after K-Pg mass extinction.











Flowering plants, new teeth and no dinosaurs: New study sheds light on the rise of mammals
Diagrams of the Rubik’s Cube-like method the team created in order to visually see how past
and present mammals fill a certain type of role or eco-cell in their ecospace
[Credit: Meng Chen et al. 2019]

«We cannot directly observe the ecology of extinct species, but body size, dietary preferences and locomotion are three aspects of their ecology that can be relatively easily inferred from well-preserved fossils,» said Chen. «By constructing the ecospace using these three ecological aspects, we can visually identify the spots filled by species and calculate the distance among them. This allows us to compare the ecological structure of extinct and extant communities even though they don’t share any of the same species.»
The team analyzed living mammals to infer how fossil mammals filled roles in their ecosystems. They examined 98 small-bodied mammal communities from diverse biomes around the world, an approach that has not been attempted at this scale. They then used this modern-day reference dataset to analyze five exceptionally preserved mammal paleocommunities ? two Jurassic Period and two Cretaceous Period communities from northeastern China, and one Eocene Epoch community from Germany. Usually Mesozoic Era mammal fossils are incomplete and consist of fragmentary bones or teeth. Using these remarkably preserved fossils enabled the team to infer ecology of these extinct mammal species, and look at changes in mammal community structure during the last 165 million years.











Flowering plants, new teeth and no dinosaurs: New study sheds light on the rise of mammals
Diagram showing the relative expansion of mammal communities
[Credit: Meng Chen et al. 2019]

The team found that, in current communities of present-day mammals, ecological richness is primarily driven by vegetation type, with 41 percent of small mammals filling eco-cells compared to 16 percent in the paleocommunities. The five mammal paleocommunities were also ecologically distinct from modern communities and pointed to important changes through evolutionary time. Locomotor diversification occurred first during the Mesozoic, possibly due to the diversity of microhabitats, such as trees, soils, lakes and other substrates to occupy in local environments. It wasn’t until the Eocene that mammals grew larger and expanded their diets from mostly carnivory, insectivory and omnivory to include more species with diets dominated by plants, including fruit. The team determined that the rise of flowering plants, new types of teeth and the extinction of dinosaurs likely drove these changes.
Before the rise of flowering plants, mammals likely relied on conifers and other seed plants for habitat, and their leaves and possibly seeds for food. By the Eocene, flowering plants were both diverse and dominant across forest ecosystems. Flowering plants provide more readily available nutrients through their fast-growing leaves, fleshy fruits, seeds and tubers. When becoming dominant in forests, they fundamentally changed terrestrial ecosystems by allowing for new modes of life for a diversity of mammals and other forest-dwelling animals, such as birds.











Flowering plants, new teeth and no dinosaurs: New study sheds light on the rise of mammals
Akidolestes cifellii (Specimen No.: NIGPAS 139381; Formation: Yixian; Age: 122.2–124.6 million years ago;
Provenance: China) is one of many of the early mammals discovered over the past 30 years
[Credit: Meng Chen]

«Flowering plants really revolutionized terrestrial ecosystems,» said Strömberg. «They have a broader range of growth forms than all other plant groups — from giant trees to tiny annual herbs — and can produce nutrient-rich tissues at a faster rate than other plants. So when they started dominating ecosystems, they allowed for a wider variety of life modes and also for much higher ‘packing’ of species with similar ecological roles, especially in tropical forests.»


Tribosphenic molars — complex multi-functional cheek teeth — became prevalent in mammals in the late Cretaceous Period. Mutations and natural selection drastically changed the shapes of these molars, allowing them to do new things like grinding. In turn, this allowed small mammals with these types of teeth to eat new kinds of foods and diversify their diets.


Lastly, the K-Pg mass extinction event that wiped out all dinosaurs except birds 66 million years ago provided an evolutionary and ecological opportunity for mammals. Small body size is a way to avoid being eaten by dinosaurs and other large vertebrates. The mass extinction event not only removed the main predators of mammals, but also removed small dinosaurs that competed with mammals for resources. This ecological release allowed mammals to grow into larger sizes and fill the roles the dinosaurs once had.


«The old theory that early mammals were held in check by dinosaurs has some truth to it,» said Wilson. «But our study also shows that the rise of modern mammal communities was multifaceted and depended on dental evolution and the rise of flowering plants.»


Author: Andrea Godinez | Source: University of Washington [April 30, 2019]



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