вторник, 4 февраля 2020 г.

Iron Age ‘warrior’ burial uncovered in West Sussex

A richly-furnished grave belonging to an Iron Age ‘warrior’ buried 2,000 years ago has been uncovered in West Sussex by UCL archaeologists.

Iron Age ‘warrior’ burial uncovered in West Sussex
Iron Age warrior grave excavated in West Sussex 
[Credit: Archaeology South-East (ASE)]
Iron weapons had been placed inside the grave, including a sword in a highly-decorated scabbard and a spear.

The burial was discovered during an excavation commissioned by Linden Homes, who are developing a site on the outskirts of Walberton, near Chichester, to create 175 new homes.

The team that made the discovery were from Archaeology South-East (ASE), the commercial branch of UCL’s Institute of Archaeology.

ASE archaeologist Jim Stevenson, who is managing the post-excavation investigations into the burial, said: “There has been much discussion generally as to who the people buried in the ‘warrior’ tradition may have been in life. Were they really warriors, or just buried with the trappings of one?

Iron Age ‘warrior’ burial uncovered in West Sussex
Sword midway through conservation and its X-rays 
[Credit: Archaeology South-East (ASE)]
“Although the soil conditions destroyed the skeleton, the items discovered within the grave suggest that the occupant had been an important individual.”

The grave is dated to the late Iron Age/ early Roman period (1st century BC – AD 50). It is incredibly rare, as only a handful are known to exist in the South of England.

X-rays and initial conservation of the sword and scabbard reveal beautiful copper-alloy decoration at the scabbard mouth, which would have been highly visible when the sword was worn in life.

Dotted lines on the X-ray may be the remains of a studded garment worn by the occupant when buried. This is particularly exciting for the archaeologists as evidence of clothing rarely survives.

Iron Age ‘warrior’ burial uncovered in West Sussex
Ceramic jar found in grave [Credit: Archaeology South-East (ASE)]
The grave also held the remains of a wooden container, preserved as a dark stain, likely used to lower the individual into the grave.

Four ceramic vessels were placed outside of this container, but still within the grave. The vessels are jars made from local clays and would usually have been used for food preparation, cooking and storage. It is likely that they were placed in the grave as containers for funerary offerings, perhaps intended to provide sustenance for the deceased in the afterlife.

Archaeologists are continuing to investigate this new discovery. By looking at other burials with weapons from the same time, they hope to find out more about the identity and social status of this individual, and the local area and landscape around that time.

Source: University College London [January 30, 2020]

* This article was originally published here

Researchers develop method to assess geographic origins of ancient Native Americans

Working with lead isotopes taken from tooth enamel of prehistoric animals, researchers at the University of Arkansas have developed a new method for assessing the geographic origins of ancient humans.

Researchers develop method to assess geographic origins of ancient Native Americans
Early Caddo village scene as envisioned by artist George C. Nelson. All of the details are based on archaeological
evidence from the Davis site or on early historical descriptions of Hasinai Caddo groups
[Credit: Institute of Texan Cultures]
John Samuelsen, doctoral candidate in anthropology and research assistant at the Arkansas Archeological Survey, analyzed linear patterning of lead isotopes on teeth from a 600- to 800-year-old skull and mandible cemetery at the Crenshaw site in southwest Arkansas. The new method allowed the researchers to compare the ancient human teeth to those of prehistoric animals, as well as rocks and soil samples, taken from the same area.

The Crenshaw site along the Red River is a culturally significant multiple-mound ceremonial center of the Caddo Indians. Previous studies have yielded conflicting interpretations of what the human skulls and mandibles reflect. Some research suggests the remains belonged to victims of violence who came from outside the region, while other research suggests the remains represent a local Caddo Indian burial practice of their own ancestors.

Samuelsen emphasized that a full evaluation of the human remains will be addressed in a future study, but he and Potra found that teeth of five of the 352 individuals tested with the new method contained isotopic signatures consistent with those found in the teeth of prehistoric animals from several sites in the area. Moreover, their isotopic signatures were inconsistent with isotopes from humans and animals from other regions.

"While our focus in this article is to establish a method for using lead isotopes to evaluate ancient human geographic origins," Samuelsen said, "this does suggest that at least these five individuals were from southwest Arkansas."

Researchers develop method to assess geographic origins of ancient Native Americans
A map showing the location of the Northern and Southern Caddo Area
[Credit: University of Arkansas]
Lead is a toxic trace metal that affects the health of biological organisms, but it is useful for determining geographic origins. Its isotopic content within human and animal tooth enamel, via food chain pathways, reflects the geology of the region in which an organism grew up. While the lead isotopes from animal teeth were successful at identifying local human remains, versus those from other geographical areas, those isotopes taken from nearby rocks were far too variable to be useful for the same purpose, Samuelsen said. Rock analysis was done by Adriana Potra, associate professor of geosciences, who co-authored the paper.

A major research concern with lead isotope studies is modern, human-caused lead contamination found on soil, rocks and human and animal remains. If modern lead from gas, mines or industrial sources has contaminated the remains, then the lead isotopes will not reflect their original locations. Even if they are uncontaminated by modern lead, the natural soil contains lead that can affect the results similarly. For these reasons, the researchers' study used three different methods to assess contamination and provided recommendations for future research.

With these concerns in mind, the researchers performed isotopic work within the metal-free, modular Radiogenic Isotope Laboratory, a "room inside a room" clean lab at the University of Arkansas. The isotopic and trace element data were collected at the Trace Element and Radiogenic Isotope Laboratory, with help from Erik Pollock, scientific research technician in the Department of Biological Sciences, and Barry Shaulis, research associate in the Department of Geosciences. High accuracy isotopic data were collected on a multi-collector, inductively coupled plasma mass spectrometer. Drilling of teeth was performed with a Leica M80 binocular microscope, housed by Celina Suarez, associate professor of geosciences.

The research project is supervised by George Sabo, director of the Arkansas Archeological Survey. Sabo is Samuelsen's graduate advisor. The research was funded by the Department of Anthropology and the Arkansas Archeological Society, in addition to the National Science Foundation. The study is being conducted in collaboration with the Caddo Nation of Oklahoma to help answer questions the tribe has about the cultural affiliation and origin of the remains.

The research, sponsored in part by the National Science Foundation, was published in the Journal of Archaeological Science.

Author: Matt McGowan | Source: University of Arkansas [January 29, 2020]

* This article was originally published here

Meteorites reveal high carbon dioxide levels on early Earth

Tiny meteorites no larger than grains of sand hold new clues about the atmosphere on ancient Earth, according to scientists.

Meteorites reveal high carbon dioxide levels on early Earth
Iron micrometeorites, like seen here under a microscope, can provide new clues about the composition
of the Earth's upper atmosphere 2.7 billion years ago [Credit: Andrew Tomkins]
Iron micrometeorites found in ancient soils suggest carbon dioxide made up 25 to 50 percent of Earth's atmosphere 2.7 billion years ago, and that pressure at sea level may have been lower than today, Penn State researchers said.

The meteorites melted as they streaked through the atmosphere and oxidized as they encountered atmospheric gases. Evidence of the oxidation remains on the tiny fragments that landed on Earth. The samples serve as a unique proxy for conditions in the upper atmosphere, the scientists said.

"This is a promising new tool for figuring out the composition of the upper atmosphere billions of years in the past," said Rebecca Payne, a doctoral candidate in geosciences and astrobiology at Penn State. Payne is lead author of the study, published recently in the journal Proceedings of the National Academy of Sciences.

The work builds on previous studies of the micrometeorites that suggested free oxygen molecules in the upper atmosphere oxidized the meteorites. Those findings would require oxygen levels on ancient Earth to be near modern day levels, a surprising conclusion that contradicts conditions expected on the young planet, Payne said.

The researchers conducted a new analysis using photochemical and climate models and determined carbon dioxide, not oxygen, likely served as the main oxidant. For this to be possible, they found carbon dioxide had to comprise at least 25 percent of the atmosphere.

Those levels of carbon dioxide would suggest a warm planet, but other climate evidence finds Earth was cool at the time and partly covered by glaciers. Lower nitrogen levels resulting in lower pressure would allow for both high carbon dioxide levels and cool conditions.

"There are data, referenced in our paper, that support lower nitrogen concentrations during this time," said Jim Kasting, Evan Pugh University Professor in the Department of Geosciences at Penn State and Payne's adviser. "Our study of micrometeorite oxidation falls in line with that interpretation. The possibility that our major atmospheric gas, nitrogen, was less abundant in the distant past is really intriguing."

The findings may help reconcile disagreements in previous studies on carbon dioxide in the deep past and climate model estimates, according to the researchers.

Previous estimates of carbon dioxide levels from billions of years ago rely on paleosols, or ancient soils, which may better reflect conditions in the lower atmosphere. Regional differences like weather or ground cover also can impact paleosols samples, and the findings from these studies often contradict each other and climate models, the scientists said.

"It was getting difficult to figure out where the agreement should have been between different paleosol studies and climate models," Payne said. "This is interesting, because it's a new point of comparison. It may help us find the right answer about atmospheric carbon dioxide in the deep past."

Don Brownlee, professor at the University of Washington, also contributed to this research.

Author: Matthew Carroll | Source: Pennsylvania State University [January 29, 2020]

* This article was originally published here


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Channel: Terry's Theories  

Apollo 17 launched on Dec.7th 1972 and landed on Dec12th 1972.There were three astronauts Commander Eugene Cernan, Lunar Module Pilot Harrison Schmitt & Command Module Pilot Ronald Evans. There mission was to explore Taurus Littrow Valley in the Taurus Mountain Range.During their mission they took a few thousand photos.I found one photo with what closely resembles what the general census thinks the Black Knight satellite looks like.If you liked the video please donate if you can. https://www.paypal.com/paypalme2/Franklin1275?locale.x=en_US
Source Photo https://www.lpi.usra.edu/resources/apollo/images/print/AS17/148/22720.jpg

Video length: 5:55
Category: Science & Technology

‘Wheeldale Road’ or 'Wade’s Causeway’, North Yorkshire Moors,...

‘Wheeldale Road’ or 'Wade’s Causeway’, North Yorkshire Moors, 2.2.20.

Initially thought to be a Roman Road travelling east to west, this view has been revised and it is likely that this track predates the Romans. A medieval stone slabbed surface makes it difficult to date but the shape, nature and camber of the route suggest Roman use. It is thought that this was a major route to the coast throughout the Iron Age.

* This article was originally published here

Mystery Planet Size Object

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Channel: Terry's Theories  

Very Large and mysterious object moving around our sun.I can't find any information on this celestial object.I know that it appears to have shown up in early 2007 as far as I can tell. It is in a small orbit at the top of our star. It is very resident to the tremendous heat of our sun.If your in the position to donate a little of your hard earned money to a hard working reacher for the truth it would go a long way https://www.paypal.com/paypalme2/Franklin1275?locale.x=en_US
Source JHelioviewer http://www.jhelioviewer.org/

Video length: 6:24
Category: Science & Technology

Did Caucasus hunter-gatherers ever live in what is now Iran?

Nope, they only lived in the Caucasus Mountains. See that's probably why they're called Caucasus hunter-gatherers, or CHG for short. But what about the hunter-gatherers from the Belt and Hotu caves in northern Iran, you might ask? Well, what about them? They're not CHG, nor are they significantly more closely related to CHG than the early farmers of the Zagros Mountains. To illustrate the point

* This article was originally published here

Wheeldale Moor Boundary or Waymarker Stones, Wheeldale Moor, North Yorkshire Moors, 2.2.20.There are...

Wheeldale Moor Boundary or Waymarker Stones, Wheeldale Moor, North Yorkshire Moors, 2.2.20.

There are six stones along the Wheeldale Moor route; these are not prehistoric but are thought to be 17th or 18th century boundary and waymarker stones.

* This article was originally published here

Making amino acids with electricity

New research from Kyushu University in Japan could one day help provide humans living away from Earth some of the nutrients they need to survive in space or even give clues to how life started.

Making amino acids with electricity
A schematic image of a flow-type electrochemical reactor for the electrochemical
amino acid synthesis [Credit: Kyushu University]
Researchers at the International Institute for Carbon-Neutral Energy Research reported a new process using electricity to drive the efficient synthesis of amino acids, opening the door for simpler and less-resource-intensive production of these key components for life.

In addition to being the basic building blocks of proteins, amino acids are also involved in various functional materials such as feed additives, flavor enhancers, and pharmaceuticals.

However, most current methods for artificially producing amino acids are based on fermentation using microbes, a process that is time and resource intensive, making it impractical for production of these vital nutrients in space-limited and resource-restricted conditions.

Thus, researchers have been searching for efficient production methods driven by electricity, which can be generated from renewable sources, but efforts so far have used electrodes of toxic lead or mercury or expensive platinum and resulted in low efficiency and selectivity.

Takashi Fukushima and Miho Yamauchi now report in Chemical Communications that they succeeded in efficiently synthesizing several types of amino acids using abundant materials.

"The overall reaction is simple, but we needed the right combination of starting materials and catalyst to get it to actually work without relying on rare materials," says Yamauchi.

Making amino acids with electricity
Electrochemical production of various amino acids from the corresponding alpha-keto acids
and hydroxylamine [Credit: Kyushu University]
The researchers settled on a combination of titanium dioxide as the electrocatalyst and an organic acid called alpha-keto acid as the key source material. Titanium dioxide is abundantly available on Earth, and alpha-keto acid can be easily extracted from woody biomass.

Placing the alpha-keto acid and a source of nitrogen, such as ammonia or hydroxylamine, in a water-based solution and running electricity through it using two electrodes, one of which was titanium dioxide, led to synthesis of seven amino acids -- alanine, glycine, aspartic acid, glutamic acid, leucine, phenylalanine, and tyrosine -- with high efficiency and high selectivity even under mild conditions.

Hydrogen, which is also needed as part of the reaction, was generated during the process as a natural result of running electricity between electrodes in water.

In addition to demonstrating the reaction, the researchers also built a flow reactor that can electrochemically synthesize the amino acids continuously, indicating the possibilities for scaling up production in the future.

"We hope that our approach will provide useful clues for the future construction of artificial carbon and nitrogen cycles in space," comments Yamauchi.

"Electrochemical processes are also believed to have played a role in the origin of life by producing fundamental chemicals for life through non-biological pathways, so our findings may also contribute to the elucidation of the mystery of the creation of life," she adds.

Source: Kyushu University [January 29, 2020]

* This article was originally published here

New CIA Spy Cloud!!

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Channel: Terry's Theories  

Sisters Terra and Latonya Scruggs find them selves face to face with a CLOUD traveling down the street as if it new where it was going. This took place in Newman Village in Virginia.
Please donate if you can it would be a great help https://www.paypal.com/paypalme2/Franklin1275?locale.x=en_US

Video length: 3:16
Category: Science & Technology

Harwood Dale Prehistoric Stone Circle or Ring Cairn, North Yorkshire, 2.2.20.

Harwood Dale Prehistoric Stone Circle or Ring Cairn, North Yorkshire, 2.2.20.

* This article was originally published here

Research sheds light on the evolutionary puzzle of primate coupling

A UTSA researcher has discovered that, whether in a pair or in groups, success in primate social systems may also provide insight into organization of human social life.

Research sheds light on the evolutionary puzzle of primate coupling
UTSA and German collaborators have discovered that, whether in a pair or in groups, success
in primate social systems may also provide insight into organization of human social life
[Credit: German Primate Center-Leibniz Institute for Primate Research]
Assistant professor Luca Pozzi in UTSA's Department of Anthropology in collaboration with Peter Kappeler, a colleague at the German Primate Center-Leibniz Institute for Primate Research, investigated how different primate societies evolved and which factors may be responsible for transitions among them.

Their reconstructions showed that the evolution from a solitary way of life to group living usually occurred via pair living. Pair living thus served as a stepping stone for group living and therefore plays a key role in the evolution of social systems.

In the course of evolution, species had to adapt to changing environmental conditions, according to Pozzi. A crucial adaptation in this process is the modification of social behavior. About half of all primate species live in groups and around one third in pairs; the rest live solitarily.

Why these different forms of social complexity evolved, how many transitions among them occurred and which factors led to the transitions was analyzed on the basis of genetic data and behavioral observations of 362 primate species.

"Living as a pair represents an evolutionary puzzle in the evolution of mammalian social systems because males could achieve higher rates of reproduction if they did not bond to a single female," says Pozzi.

Yet evolutionary biologists still struggle to find the advantages of pair living for males, according to Peter Kappeler, who is one of the lead researchers of the study.

At first glance the two current hypotheses on the development of pair living--the female distribution hypothesis and the paternal care hypothesis--seem to be mutually exclusive.

Yet results in this work indicate that the two factors may be complementary. Initially it was believed that an ecological change in the habitat led to female spatial separation and that solitary males, which previously had several females living in their territory, were subsequently only able to gain access to one female. Paternal care resulting from the pair formation in turn increased the survival probability of the offspring and thus reinforced pair living.

The further transition to group living was possible through an improvement of the ecological situation, which allowed related females to live in close proximity. These could then be joined by one or more males.

"However, the pair bond typical for humans within larger social units cannot be explained with our results, since none of our recent ancestors lived solitarily. Nevertheless, the advantages of paternal care also may have led to a consolidation of pair living in humans," said Kappeler.

"The evolution of complex social systems in mammals, and more specifically in primates, is a challenging and exciting area of research. Our study shows that pair living--although rare--might have played a critical role in it," says Pozzi.

The research was published in Science Advances.

Author: Milady Nazir | Source: University of Texas at San Antonio [February 03, 2020]

* This article was originally published here

New UFOs found in old NASA Apollo 17 images from 48 years ago.

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Apollo 17 launched from John F. Kennedy Space Center on Dec. 7th at 5:33 AM.
The Apollo 17 had a three man crew Commander Eugene Cernan, Lunar Module Pilot Harrison Schmitt & Command Module Pilot Ronald Evans.
There mission was to explore Taurus Littrow (it is a valley located in the Taurus Mountain range).Theses photos that I am showing you were taken by these astronauts & these photos also show triangular shaped objects in the background in a low earth orbit. Now I ask you are we looking at maybe something that we weren't meant to see. Were these crafts, UFOs, UAPs
whatever you want to call them caught on film by accident 43 years ago? Or is it space junk in the
shape of a triangle or dust on the lens. You tell me. If you feel like donating that wood be great thanks Terry https://www.paypal.com/paypalme2/Franklin1275?locale.x=en_US

Video length: 8:27
Category: Science & Technology

Prehistoric Inspired Sculpture, Whitby Museum and Gallery, Whitby, North Yorkshire, 2.2.20.

Prehistoric Inspired Sculpture, Whitby Museum and Gallery, Whitby, North Yorkshire, 2.2.20.

* This article was originally published here

One single primitive turtle resisted mass extinction in the northern hemisphere

Sixty-six million years ago, in the emerged lands of Laurasia -now the northern hemisphere- a primitive land tortoise, measuring about 60 cm, managed to survive the event that killed the dinosaurs. It was the only one to do so in this area of the world, according to a Spanish palaeontologist who has analysed its peculiar fossils, found in France.

One single primitive turtle resisted mass extinction in the northern hemisphere
A reconstruction of Laurasichersis relicta which lived in the northen hemisphere 66 millons years ago
[Credit: José Antonio Peñas (SINC)]
All turtle species we know of today are descendants of two lineages that separated during the Jurassic, more than 160 million years ago. But their members were not the only ones that existed. There had been many groups of primitive tortoises before them, in an earlier evolutionary position.

Some of these ancient reptiles managed to survive at a time when dinosaurs dominated the Earth. However, virtually all of the early groups of turtles disappeared after an asteroid impact that took place 66 million years and wiped out 70% of life on the planet.

Only the so-called "horned turtles" or meiolaniids managed to hold out, more specifically in Gondwana, the current southern hemisphere, according to fossils found in Oceania and South America. Their last representatives managed to co-exist relatively recently with humans, who hunted them to extinction. No other primitive turtle had appeared in the records of the last 66 million years.

After 10 years of study, the palaeontologist Adán Pérez García, from the Evolutionary Biology Group of the National University of Distance Education (UNED, Spain), now confirms that, in the northern hemisphere, on the ancient continent called Laurasia, a primitive land turtle also survived the mass extinction of the late Cretaceous period.

This was Laurasichersis relicta, an extinct turtle genus and species that corresponds to a new form, with very peculiar anatomical characteristics, and whose lineage evolved independently from that of the Gondwana tortoises, from which it separated 100 million years earlier.

"The reason why Laurasichersis survived the great extinction, while none of the other primitive North American, European or Asian land turtles managed to do so, remains a mystery," Pérez García, the sole author of the paper published in Scientific Reports, has confided to Sinc.

The impact of the asteroid plunged the Earth into a spiral of gas emissions, molten material and acid rain that caused a sudden warming of the climate and transformed the landscapes in which the turtles lived.

One single primitive turtle resisted mass extinction in the northern hemisphere
Laurasichersis relicta, an extinct turtle genus and species that corresponds to a new form
[Credit: José Antonio Peñas (SINC)]
"The fauna of European turtles underwent a radical change: most of the forms that inhabited this continent before the extinction disappeared, and their role in many ecosystems was left vacant until the relatively rapid arrival of new groups from various places in North America, Africa and Asia," the palaeontologist points out.

All of them, identified in these new ecosystems, seemed to belong to the two lineages that have persisted to this day, but the new study allows us to recognize that they were not alone. The appearance in a site in northeastern France of fossils of the shell, limbs and skull of Laurasichersis relicta shows that this primitive species also survived the mass extinction event in Laurasia.

However, its origin stems from another continent: "It is the last representative of a group previously identified in China and Mongolia, where it was known since the Jurassic, more than 100 million years before the new European Laurasichersis turtle existed. This group arrived on this continent very shortly after the end of the Mesozoic, 66 million years ago," says the researcher.

The shell of the newly discovered turtle was just over 60 cm long during adulthood and, like other primitive reptiles, it could not retract its neck into its shell to conceal its head from predators. This physical limitation allowed it to develop other protective mechanisms such as an armor with large, mutually linked spikes, which were hard structures located on the neck, legs and tail.

Its peculiar shell is one of the most remarkable features of this reptile and one of the characteristics that make it unique. This complex structure was made up of numerous plates. "Although the number of plates is usually the same in most turtles, the ventral shell region of the new species was provided with a greater number of these elements than those known in any other turtle," Pérez García stresses.

After the 10-km-diameter meteorite hit the Earth, the large dinosaurs ceased to be part of the landscape, but the turtle, which lived in humid environments with forest areas, coexisted with new predators. The latter quickly dominated the positions of the food chain that had remained available when most animals disappeared.

Author: Adeline Marcos | Source: Spanish Foundation for Science and Technology (FECYT) [February 03, 2020]

* This article was originally published here

Extremely Fast Moving White Object Or UFO Over Ukraine.

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Channel: Terry's Theories  

If you like the channel and the videos and your able please donate at https://www.paypal.me/Franklin1275?locale.x=en_US

I had two videos emailed to me by YouTube channel Strannik Vechnyi that was recorded by his drone over a forest close to chernobyl. The video shows white objects hard to make out a shape but they are moving at extreme speeds. If you have a video you would like me to look at that has to do with Ufology please email me at terrystheories@outlook.cok
Source YouTube channel is Strannik Vechnyi https://www.youtube.com/channel/UC5eFuuafr7jVLy0wweXDGFg

Video length: 4:25
Category: Science & Technology

‘Rudston Monolith’ Bronze Age Standing Stone, Rudston, North Yorkshire, 2.2.20.

‘Rudston Monolith’ Bronze Age Standing Stone, Rudston, North Yorkshire, 2.2.20.

* This article was originally published here

How and when spines changed in mammalian evolution

A new study from Harvard University and the Field Museum of Natural History sheds light on how and when changes in the spine happened in mammal evolution. The research reveals how a combination of developmental changes and adaptive pressures in the spines of synapsids, the extinct forerunners of mammals, laid the groundwork for the diversity of backbones seen in mammals today.

How and when spines changed in mammalian evolution
Illustration of Dimetrodon, pelycosaur synapsid, showing the elaborate backbone sail. This study shows that despite
their bizarre sails, it is likely that their vertebral movements were relatively uniform along their back, more
similar to living lizards or salamanders than to mammals [Credit: Copyright 2019 Mark Witton]
By comparing the biomechanics of two modern animals, cat and lizard, and CT scans of synapsid fossils, the researchers overturned the traditional notion that the gradual accumulation of different regions (or independent sections) of the spine alone account for its evolving complexity. New evidence suggests that regions (like the thorax and lower back) evolved long before new spinal functions, such as bending and twisting. The study points to the idea that the right selective pressures or animal behaviors combined with existing physical regions played a significant role in the evolution of their unique functions.

The findings by Stephanie Pierce, Associate Professor of Organismic and Evolutionary Biology and Curator of Vertebrate Paleontology at Harvard, and postdoctoral researcher Katrina Jones tap into the larger question of how mammals, including humans, evolved over millions of years.

Modern mammals, for instance, have developed compartmentalized spinal regions that take on a number of diverse shapes and functions without affecting other spinal regions. This has allowed the animals to adapt to different ways of life, explained Jones.

In previous research, the authors showed that extinct pre-mammalian land animals developed these small but distinct regions during evolution.

"What we were able to show in 2018 was that even though all the vertebrae looked very similar in early mammal ancestors they had subtle differences and those subtle differences created distinct developmental regions," Pierce said. "What we're showing with this new study is that those distinct regions were really important as they provided the raw material that facilitated functional differentiation to happen. Basically, if you don't have these distinct developmental regions in place and you have a selective pressure, all the vertebrae are going to adapt in the same way."

It's long been thought that developing different spinal regions is one important step in evolving backbones with many functions, but Pierce and Jones show that this isn't enough. An evolutionary trigger was also required, in this case the evolution of a highly active lifestyle that put new demands on the backbone.

How and when spines changed in mammalian evolution
Exhibit specimen of Edaphosaurus, a pelycosaur synapsid, from the collections
 at the Museum of Comparative Zoology. Pelycosaurs are the most ancient fore-
runners of mammals. This study shows that despite their bizarre sails, it is
likely that their vertebral movements were relatively uniform along their
back, more similar to living lizards or salamanders than to mammals
[Credit: Harvard University Museum of Comparative Zoology]
Jones said, "We're trying to get at something that's quite a fundamental evolutionary question which is: How does a relatively simple structure evolve into a complex one that can do lots of different things? Is that determined by the limitations of development or natural selection related to the behavior of the animal?"

The researchers compared the spines of two animals essentially on opposite ends of the evolutionary and anatomical spectrum: cat, which has highly developed spinal regions, and lizard, which has a pretty uniform backbone. They looked at how each animal's spinal joints bent in different directions to measure how the form of the vertebrae reflects their function. They determined that while some spinal regions can function differently from one to the other, others do not; for example, the lizard's backbone comprised several distinct regions, but they all acted in the same way.

Researchers including Kenneth Angielczyk from the Field Museum of Natural History then turned their focus to finding out when different regions started taking on different functions in the evolution of mammals. They took the cat and lizard data showing that if two joints in the spine looked different, then they tended to have different functions. With that, they mapped out how spinal function in those fossils changed through time.

"The earliest ancestors of mammals have a remarkably good fossil record, considering that those animals lived between about 320 and 250 million years ago," Angielczyk said.

The researchers found that despite having developmental regions capable of performing different functions, the level of functional variation seen in mammals today did not start to take hold until late in synapsid evolution.

"We then hypothesized that maybe it was the evolution of some new mammalian behaviors that helped trigger this [in these late synapsids] and provided the natural selection that could exploit the regions that were already there," Jones said.

Their findings fit with observations that the group in which this functional diversity occurs -- the cynodonts, which directly preceded mammals -- have a number of mammalian features, including evidence they could breathe like a mammal. The researchers believe that these mammal-like features shifted the job of breathing away from the backbone and ribs to the newly evolved diaphragm muscle, releasing the spine from an ancient biomechanical constraint. This enabled the backbone to adapt to interesting new behaviours, such as grooming fur, and take on new functions.

The next step for Pierce and Jones is to clarify what those functions looked like in these extinct animals.

The study is published in Nature Ecology and Evolution.

Source: Harvard University [February 03, 2020]

* This article was originally published here


322 views   40 likes   2 dislikes  

Channel: Terry's Theories  

This is the last part in what turned into a three part series on some of the footage that I acquired over 2019. I hope you guys enjoy. All source information can be found in my previous videos.

Video length: 13:14
Category: Science & Technology


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