A geochemist, from UC Santa Barbara, has been studying Samoan volcanoes and discovered evidence of the planet’s early formation is still trapped inside the earth. Known as hotspots, volcanic island chains such as Samoa can be ancient primordial signatures from the early solar system that have survived billions of years.
Matthew Jackson, an associate professor in UCSB’s Department of Earth Science, and colleagues used high-precision lead and helium isotope measurements to untangle the chemical the chemical composition and geometry of the deep mantle plume feeding Samoa’s volcanoes. Their findings were published yesterday in the journal Nature.
Volcanoes are usually located at the point where two tectonic places meet and are created when those plates collide or diverge. Hotspot volcanoes are an exception as they are not located at plate boundaries, but instead represent the anomalous melting in the interior of the plates.
Such intraplate volcanoes form above a plume-fed hotspot where the Earth’s mantle is melting. The plate moves over time- at about the same rate that human fingernails grow (3 inches a year)- and eventually the volcano moves from the hotspot and becomes extinct. A new volcano forms in its place over the hotspot and process repeats itself until a string of volcanoes evolves.
“So you end up with this linear trend of age-progressive volcanoes,” Jackson said. “On the Pacific plate, the youngest is in the east and as you go west, the volcanoes are older and more deeply eroded. Hawaii has two linear trends of volcanoes- most underwater- which are parallel to each other. There’s a southern trend and a northern trend.”
Due to the volcanic composition of parallel Hawaiian trends being fundamentally different, Jackson and his team made the decision to look for evidence in other hotspots. In Samoa, they found three volcanic trends exhibiting three different chemical configurations as well as a fourth group of a late-stage eruption on top of the third trend of volcanoes. These different groups demonstrate distinct compositions.
“Our goal was to figure out how we could use this distribution of volcano compositions at the surface to reverse-engineer how these components are distributed inside this upwelling mountain plume at depth,” Jackson said.
Each of the four distinct geochemical compositions, or endmembers, that the scientists identified in Samoan lavas contained low Helium-3 (He-3) and Helium-4 (He-4) ratios. The startling discovery was that they all showed evidence for mixing a fifth, rare primordial component consisting of high levels of He-3 and He-4.
“We have really strong evidence that the bulk of the plume is made up of the high Helium-3, -4 component,” Jackson said. “That tells us that most of this plume is primordial material and there are other materials hosted inside of this plume with low Helium-3, -4, and they are likely crustal materials sent into the mantle at ancient subduction zones.”
This unique isotope topology unveiled by the researchers’ analysis indicates that the four low-helium endmembers do not mix efficiently with one author. However, each of them mixes with the high He-3 and He-4 component.
“This unique set of mixing relationships requires a specific geometry for the four geochemical flavours within the upwelling plume: They must hosted within a matrix that is composed of the rare fifth component with the high He-3,” Jackson explained. “This new constraint on plume structure has important implications for how deep mantle material is entrained in plumes, and it gives us the clearest picture yet for the chemical structure of an upwelling mantle plume.”
Co-authors of the paper include Stanley R. Hart, Jerzy S. Blustajn and Mark D. Kurz from the Woods Hole Oceanographic Institution, Jasper G. Konter from the University of Hawaii and Kenneth A. Farley from the California Institute of Technology. The research was funded by the National Science Foundation.
Contributing Source: UC Santa Barbara
Header Image Source: WikiPedia
The mountain range was similar in size to the Himalayas and spanned at least 2,500 kilometres of what is now west Africa and northeast Brazil, which at the time were part of the supercontinent Gondwana.
“Just like the Himalayas, this range was eroded intensely because it was so huge. As the sediments washed into the oceans they provided the perfect nutrients for life to flourish,” said Professor Daniela Rubatto of the Research School of Earth Sciences at The Australian National University (ANU).
“Scientists have speculated that such a large mountain range must have been feeding the oceans because of the way life thrived and ocean chemistry changed at this time, and finally we have found it.”
The discovery is the earliest evidence of Himalayan-scale mountains on Earth.
“Although the mountains have long since washed away, rocks from their roots told the story of the ancient mountain range’s grandeur,” said co-researcher Professor Joerg Hermann.
“The range was formed by two continents colliding. During this collision, rocks from the crust were pushed around 100 kilometres deep into the mantle, where high temperatures and pressures formed new minerals.”
While the mountains eroded, the roots arose back to the surface, to be collated in Togo, Mali and northeast Brazil, by Brazilian co-researcher Carlos Ganade de Araujo, from the Universit of Sao Paolo.
Dr. Ganade de Araujo realised the samples were unique and brought the rocks to ANU where, using world-leading equipment, the research team accurately identified that the rocks were of a similar age, and had been formed at similar, great depths.
The research included specialists from various different areas of Earth Science sharing their knowledge, said Professor Rubatto.
“With everyone cooperating to study tiny crystals, we have managed to discover a huge mountain range,” she said.
Contributing Source: Australian National University
Header Image Source: Carlos Ganade de Araujo
Researchers from Syracuse University’s College of Arts and Sciences are pairing chemical analyses with micropalaeontology- the study of tiny fossilised organisms- to obtain a better understanding of how global marine life was affected by a rapid warming event over 55 million years ago.
Their findings are the subject of an article published in the journal Paleocenography (John Wiley & Sons, 2014).
“Global warming impacts marine life in complex ways, of which the loss of dissolved oxygen [a condition known as hypoxia] is a growing concern,” says Zunli Lu, assistant professor of Earth sciences and a member of Syracuse’s Water Science and Engineering Initiative. “Moreover, it’s difficult to predict future deoxygenation that is induced by carbon emissions, without a good understanding of our geologic past.”
Lu says this type of deoxygenation results in larger and thicker oxygen minimum zones (OMZs) in the wold’s oceans. An OMZ is the layer of water in an ocean where oxygen saturation is at its lowest.
Much of Lu’s work revolves around the Paleocene-Eocene Thermal Maximum (PETM), a well-studied analogue for modern climate warming. Documenting the expansion of OMZs during the PETM is problematic due to the lack of a sensitive, widely applicable indicator of dissolved oxygen.
In order to address the problem, Lu and his colleagues have started working with iodate, a type of iodine that is apparent in oxygenated waters only. By analysing the iodine-to-calcium ratios in microfossils, they are able to estimate the oxygen levels because of the lack of sensitive widely applicable indicator of dissolved oxygen.
Fossil skeletons of a group of protists known as foraminiferas have long been used for palaeo-environmental reconstructions. Developing an oxygenated proxy for foraminifera is important to Lu because it could allow him to study the extent of OMZs “in 3-D,” since these popcorn-like organisms have been abundant in ancient and modern oceans.
“By comparing our fossil data with oxygen levels simulated in climate models, we think OMZs were much more prevalent 55 million years ago than they are today,” he says, adding that OMZs likely expanded in the PETM, prompting mass extinction on the seafloor.”
Lu thinks analytical facilities that combine climate modeling with micropalaeontology will aid scientists in anticipating trends in ocean deoxygenation. Already, it’s been reported that modern-day OMZs, such as those in the Eastern Pacific Ocean, are beginning to expand. “They’re natural laboratories for research,” he says, regarding the interactions between oceanic oxygen levels and climate changes.
Contributing Source: Syracuse University
Header Image Source: Flickr
These, now extinct, giant kangaroos were most likely unable to hop and used a more rigid body posture to move their hindlimbs one at a time, says a study published October 15th, 2014 in the open-access journal PLOS ONE by Christine Janis from Brown University and colleagues.
The “short-faced”, large bodied sthenurine kangaroos- a now extinct relative to modern-day kangaroos- first appeared in the middle Miocene and became extinct in the late Pleistocene. The largest of these kangaroos had an estimated body mass of 240 kg, almost three times larger than that of the biggest currently living kangaroos. Scientists think that kangaroos of this size may not have had the physical ability to hop. Analysis of different sthenurine species limb bone when compared to other kangaroos indicates various anatomical differences, especially in the larger species.
The physical differences the authors of this study discovered suggest that the large kangaroo species lacked various specialised features for rapid hopping, but had anatomy suggesting they supported their body weight with an upright posture and were able to support their weight on one leg at a time using their larger hips, knees, and stabilised ankle joints. Previous studies described that sthenurines’ specialised forelimbs and rigid lumbar spine would limit their ability to move slowly, using the tail as a fifth limb, as is typical in smaller kangaroos.
Instead, the authors propose that sthenurines adopted a walking gait on two hind legs, in the smaller and earlier forms, this gait may have been used as an alternative gait to using the tails as fifth limb at slower speeds. Larger Pleistocene kangaroos may have used this gait exclusively as they evolved larger body sizes, where hopping quickly was no longer possible.
“People often interpret the behavior of extinct animals as resembling that of the ones known today, but how would we interpret a giraffe or an elephant known only from the fossil record? We need to consider that extinct animals may have been doing something different from any of the living forms, and the bony anatomy provides great clues,” said Christine Janis.
If you would like to read the full paper, free access is available: http://dx.plos.org/10.1371/journal.pone.0109888
Contributing Source: PLOS
Header Image Source: WikiPedia
Archaeologist Anna Ihr’s research has led to fascinating discoveries in two completely different regions of the world – in the old Swedish trade centre Old Lödöse along the Göta Älv river and in Qalhāt, the former capital of the Hormuz Kingdom in Oman. Ihr’s research shows that primary glass was produced in Sweden 300 years before the reign of King Gustav Vasa. It also shows that dried fish was once used to fuel ceramic kilns in Oman.
In Old Lödöse, Ihr has found pieces of a cracked clay crucible with glass remains inside and attached stones underneath. Nearly 100 kilos of this material has been uncovered.
‘The dating of my finds shows that glass was produced in Old Lödöse prior to 1260. That’s 300 years earlier than the previously oldest known written sources, which are from 1556. This means that Sweden’s history of glass production now has to be revised,’ she says.
The thesis describes how different vitrified, or glassy, materials can be interpreted and analysed. It can be very difficult to interpret how a piece of glass was made. It could have been made intentionally or unintentionally. Glaze is an example of intentionally produced glassy material. Glass describes a state of a processed material. Vitrified slag from blast furnaces is one example of unintentionally material.
‘In order to determine the difference between intentionally and unintentionally processed materials, you need a certain type of scientific analysis which is very rarely performed in Scandinavia. This is the reason why glass never has been studied in this perspective in Sweden,’ says Ihr.
Three ceramic kilns have been located and excavated in Qalhāt. The analyses show that they were fuelled with dried fish, and the ashes and the minerals in the sand fused and formed a glassy slag, vitrifying the inside of the kilns.
‘The use of dried fish was a conscious choice, though.’
Ihr hopes that her doctoral thesis will contribute to a broader understanding of how certain societies were organised. In glass artefacts which reflect a well-structured community, as in Old Lödöse, archaeologists can extract traces of trade specialisation, technology, rituals and decision making – so called advanced societies. In other cases, vitrified assemblages may reveal a community which-was not advanced. One example of this is the vitrified dung found in an old settlement in South Africa.
‘My studies show that glass production may be used as an indicator of an advanced society. From processed materials it is possible to extrat imanent social information, which may say much of a lost society’ says Anna Ihr.
The fossils belong to 500-million-year-old blind water creatures, known to scientists as “vetulicolians” (pronounced: ve-TOO-lee-coal-ee-ans).
These marine creatures, which have been described as alien-like in appearance, were “filter-feeder” creatures, shaped like a figure-of-8. Their odd anatomy has meant that they have not been placed correctly in the tree of life, that is, until now.
In a new paper published in BMC Evolutionary Biology, researchers at the University of Adelaide and the South Australian Museum argue for an alteration in the way that these creatures are viewed, placing them in the same group as vertebrate animals, such as humans.
“Although not directly related to humans in the evolutionary line, we can confirm that these ancient water creatures are among our distant cousins,” says the lead author of the paper, Dr. Diego Garcia-Bellido, ARC Future Fellow with the University’s Environment Institute.
“They are close relatives of vertebrates- animals with backbones, such as ourselves. Vetulicolians have a long tail supported by a stiff rod. This rod resembles a notochord, which is the precursor of the backbone and is unique to vertebrates and their relatives,” he says.
The first specimens were studied back in 1911, but it took until 1997 for the fossils to be classified as a group on their own: the vetulicolians. These fossils have now been discovered across the world including: Canada, Greenland, China and Australia.
The latest insights to vetulicolians have derived from new fossils found on Kangaroo Island off the coast of South Australia, which have been named Nesonektris (Greek for “Island Swimmer).
“Vetulicolians are further evidence that life was very rich in diversity during the Cambrian period, in some aspects more than it is today, with many extra branches on the evolutionary tree,” Dr. Diego Garcia-Bellido says. “They were simple yet successful creatures, large in number and in distribution across the globe, and one of the first representations of our cousins, which include sea squirts and salps.”
Contributing Source: University of Adelaide
Header Image Source: University of Adelaide/South Australian Museum
“Our study provides comprehensive insight into how nearly all the cotinga species are related to each other going all the way back to the common ancestor,” says lead author Jake Berv, a Ph.D in the Fuller Evolutionary Biology Lab at the Cornell Lab of Ornithology. “No previous attempts to understand the evolutionary history of this group have included genetic samples from nearly all the existing species.”
Berv began sequencing DNA samples and collecting data back in late 2010 whilst working as a lab technician at Yale University with co-author Prof. Rick Prum, a leading expert on cotingas. The understanding of how one species is related to another within this group enables scientists to trace the evolution of certain traits and behaviours.
Berv and Prum have already begun this process. They wanted to learn if the evolution of differently coloured males and females in this group of birds (sexual dimorphism) is directly linked the to the breeding system in which males have multiple mates (polygyny). Darwin first proposed the theory that the increased pressure of sexual selection in polygynous birds encouraged the development of colour differences between the sexes. This seems to be correct for many species- but not the cotingas. When Berv and Prum examined the patterns of evolution for these two traits across their new tree of life, it turned out that they didn’t quite match up perfectly. The statistics they calculated also supported the conclusion that these traits might be evolutionary “de-coupled” in the cotingas.
Sexual selections seems to have played a crucial role in the evolution on non-plumage gender differences in some cotinga species.
“In one case, the Screaming Piha, the males and females look alike but the male sings one of the loudest songs on the planet,” says Yale’s Rick Prum. “That means male-female plumage difference alone is not evidence for sexual selection because sexual selection is also driving other traits such as voice and behaviour.”
“One of the biggest analytical differences between what we’ve done and past work is that we used a ‘species tree’ approach, which is potentially more accurate than what is typically applied to genetic data,” says Berv. “We ran our data through more traditional types of analyses as well, and all of them strongly supported a consistent evolutionary ‘tree of life’. We hope other scientists who are interested in these birds take our phylogeny and do all sorts of great things with it.”
Contributing Source: Cornell University
Header Image Source: Wikimedia
Archaeologists from the University of Leicester have made what has been described by many as a “once-in-a-career” discovery of the decorated bronze remains of an Iron Age chariot.
A team from the University’s School of Archaeology and Ancient History has unearthed a vast array of rare bronze fittings from a 2nd or 3rd century BC chariot, which appears to have been buried as a religious offering.
The team of archaeologists discovered the remains during an ongoing excavation of the Burrough Hill Iron Age hillfort, located near Melton Mowbray in Leicestershire.
The School has led a 5-year project there since 2010, allowing students and volunteers to obtain valuable experience of archaeological excavations.
Burrough Hill is owned by the education charity, the Ernest Cook Trust, which has also funded site tours and school visits to the excavation.
While digging a large, deep pit near the remains of a house within the hillfort, a group comprising of four students uncovered a piece of bronze in the ground− before unveiling a concentration of further parts close by.
Taken together, the pieces are easily recognisable as a matching set of bronze fittings from a mid to late Iron Age chariot. As a group of two or more base metal prehistoric artefacts this assemblage is covered under the Treasure Act.
After being carefully cleaned, decorative patterns are clearly seen in the metalwork− including a triskele motif displaying three waving lines, similar to that of the flag of the Isle of Man.
Nora Batterman, from the University of Leicester was one of the students who made the discovery. She said: “Realising that I was actually uncovering a hoard that was carefully placed there hundreds of years ago made it the find of a lifetime. Looking at the objects now they have been cleaned makes me even more proud, and I can’t wait for them to go on display.”
It appears the pieces have been gathered in a box prior to being planted in the ground upon a layer of cereal chaff and burnt as part of a religious ritual. The chaff may have doubled as a “cushion” for the box and also the fuel for the fire.
After the burning, the entire deposit was covered with a layer of burnt cinder and slag− where it lay undisturbed for over 2,200 years until the team discovered it.
The archaeologists believe the burial might have taken place to mark a new season, or the final closure or dismantling of a house at the fort.
Dr. Jeremy Taylor, Lecturer in Landscape Archaeology at the University’s School of Archaeology and Ancient History and co-director of the Burrough Hill field project, said: “This is a matching set of high-decorated bronze fittings from an Iron Age chariot− probably from the 2nd or 3rd century BC.
“This is the most remarkable discovery of material we made at the Burrough Hill in the five years we worked on the site. This is a very rare discovery, and a strong sign of the prestige on the site.
“The atmosphere at the dig on the day was a mix of ‘tremendously excited’ and ‘slightly shell-shocked’. I have been excavating for 25 years and I have never found one of these pieces− let alone a whole set. It is a once-in-a-career discovery.”
John Thomas, co-director of the project added: “It looks like it was a matching set of parts that was collected and placed in a box as an offering, before being placed in the ground. Iron tools were placed around the box before it was then burnt, and covered in a thik layer of cinder and slag.
“The function of the iron tools is a bit of a mystery, but given the equestrian nature of the hoard, it is possible that they were associated with horse grooming. One piece in particular has characteristics of a modern curry comb, while two curved blades may have been used to maintain horses hooves or manufacture harness parts.”
The parts have been taken to the University of Leicester’s School of Archaeology and Ancient History for further analysis− and the archaeologists hope that the atrefacts will be put on display in due course.
Until then, there will be a temporary display of the objects at the Melton Carneige Museum, Melton Mowbray, Leicestershire, from Saturday October 18th until Saturday December 13th.
Contributing Source: University of Leicester
Header Image Source: University of Leicester
As Julio Cesar de A. Marsola and his colleagues explain in the journal Alcheringa, their discovery is of great importance due to a number of reasons. Compared to the abundance of eggs from non-avian dinosaurs, discoveries of complete eggs from Mezosoic birds are somewhat scarce.
Although there were no remains found inside this particular egg, known formally as LPRP USP-0359, the team’s extensive tests revealed crucial information about both the egg itself and its wider context. Their observations show that LPRP-USP0359 is, in fact, one of the smallest and thinnest shelled Mesozoic bird eggs ever discovered.
Furthermore, similarities between the Brazilian egg and specimens found in Argentina indicate an affinity between them as Ornithothoraces. Due to further similarities in where and how they eggs were found, the researchers suggest that the two birds may also have preferred the same types of breeding and nesting habitats- important clues that will aid palaeontologists in creating a more detailed picture of the South America’s Mesozoic past.
Contributing Source: Taylor & Francis
Header Image Source: Wikimedia
Parasites use their hosts to simplify their own lives. To do this, they evolved features that are so extreme that it is often impossible to compare them to other species. The evolution of these extreme adaptations is often too difficult to reconstruct. The research group lead by Prof. Dieter Ebert from the Department of Environmental Science at the University of Basel has now found the missing link that explains how this large group of extreme parasites, the microsporidia, has evolved. Scientists from Sweden and the U.S supported the team in their work.
Microsporidia are a large group of extreme parasites that occupy humans and animals and create substantial damage for health care systems and agriculture; there are over 1,200 known species. They live inside their host’s cells and have highly specialised features, including: They are only able to reproduce inside the host’s cells, they have the smallest known genome of all organisms containing a cell nucleus (eukaryotes) and they don’t posses any mitochondria of their own (the cell’s power plant). Along with all this, they developed a specialised infection apparatus, the polar tube, which they use to insert themselves into the cells of their host. As a result of their phenomenal high molecular evolution rate, genome analysis has thus far been rather unsuccessful: their great genomic divergence from all other known organisms further complicates the study of their evolutionary lineage.Between fungi and parasite
The team of zoologists lead by Prof. Dieter Ebert has been studying the evolution of microsporidia for a number of years. When they discovered a new parasite in water fleas a couple of years ago, they classified this undescribed species as a microsporidium, as it possessed the unique harpoon-like infection apparatus (the polar-tube), one of the classifying features of microsporidia. The analysis of the entire genome contained several surprises: The genome resembles more that of a fungi than a microsporidium and, in addition, also contains a mitochondrial genome. The new species, now named Mitosporidium daphniae, therefore represents the missing link between fungi and microsporidia.
With the help of scientists in Sweden and the U.S., the Basel researchers rewrote the evolutionary history of microsporidia. Firstly, they demonstrated that the new species derives from the ancestors of all known microsporidians and further, that the microsporidians are derivative from the most ancient fungi; there its exact place in the tree of life has finally been discovered. Further research has confirmed that the species does in fact have a microsporidic, intracellular and parasitic lifestyle, but that its genome is rather atypical for a microsporidium. It resembles much more the genome of their fungal ancestors.Genome modifications
The scientists came to the conclusion that the microsporidia adopted intracellular parasitism first and later altered their genome significantly. These genetic adaptations include the loss of mitochondria, as well as extreme metabolic and genomic simplification. “Our results are not only a milestone for the research on microsporidia, but they are also of great interest to the study of parasitic-specific adaptations in evolution in general”, explains Ebert.
Contributing Source: Universität Basel
Header Image Source: WikiPedia
Some dismiss the use of these techniques in archaeology, arguing the methods are old and demonstrate only evolutionary, rather than revolutionary, improvement. But Stonehenge is a World Heritage Site spread over a large area and while it has been intensively studied for decades, physical digs are now extremely restricted.
Instead, over the past four years, the Stonehenge Hidden Landscape Project (SHLP) – a collaboration between the universities of Birmingham, Vienna, Bradford, St Andrews, Nottingham and Ghent with the National Trust and English Heritage – used geophysical survey techniques such as earth resistance, magnetometry, ground-penetrating radar and electromagnetic induction.
It’s true that these have been standard issue in the geophysicist’s armoury for some time, so the sceptical observer may feel justified. But what is not apparent is the scale of the survey and the quantity and quality of data unearthed.Digging up new data
The main technique used by the project was magnetometry. This reveals patterns by recording the magnetic properties of ferrous elements in soil or as left behind by human activity such as burning. More than 12km2 around Stonehenge was surveyed using magnetometry, accomplished by using arrays of up to 10 fluxgate sensors to detect the magnetic fields, mounted on a customised non-magnetic cart pulled by quad bikes fitted with navigation aids. Sampling information at a resolution of 10cm x 25cm, this process generated a lot of data.
By way of comparison, using ground-penetrating radar – which beams radio waves into the earth and records their reflections bouncing back from solid objects underground – the team covered a smaller area at much higher resolution, using a system of 16 sensors at a resolution of 8cm x 8cm. The key to the success of both techniques is the ability to accurately pinpoint and record the location of each of the millions of measurements. The use of real time GPS and robotic guidance has shown that computerised, software-controlled techniques like these can provide huge amounts of accurate data and reveal buried features.
The data from the magnetometers is gathered as the sensor array is pulled at 20mph or more, while the ground radar sensors move at a fast walking pace. The difference in speed is due to the nature of the properties being measured. The first is a passive sensor which records the earth’s ambient magnetic field, while the second is an active system where radio energy is transmitted into the ground and a receiver waits to collect the energy reflected, which by necessity takes longer.
As a result magnetometer surveys will always be cheaper to conduct and this explains in part why they’re highly favoured by commercial surveyors. But for successful use of magnetometry there must be a measurable contrast in magnetic properties of the archaeological features being searched for, for example the backfill in pits or ditches, and the surrounding soil. Fortunately the chalk landscape at Stonehenge is blessed with a low magnetic background which provides the high contrast needed.New discoveries, new context
The results of the magnetic survey are a great starting point to consider how technological changes have altered our perspective of Stonehenge. Within the magnetic map we can see debris from the modern free festival in the 1970s-80s, trenches dug for troop practice during World War I a century ago, and evidence left from the earliest uses of the landscape.
These images show the variation in magnetic field. The mid range is based around zero, with black, positive values tending to show accumulations of magnetic soil. In these images we can see soil-filled ditches and pits, and the location of former timber posts that once made up henges or supports for barrows or buildings.
The surveying has revealed 17 entirely undiscovered monuments as well as radical new information about existing sites. The impression is that far from standing in splendid isolation, Stonehenge was really part of an complex, ordered, ritual landscape. It’s likely to have been peppered by small shrines that were part of the Stonehenge experience for the Neolithic Britons of the time.
Even if you were allowed to excavate freely at Stonehenge today it would be impossible to understand the site in its landscape context without the technology employed during the project. While the cynical observer may think that the geophysical techniques have only marginally improved with age, this underestimates the technological advances in how they are practically used, and the effect this has on the quality of data they can generate.
The classical historian Mary Beard recently suggested that archaeological discoveries are now more likely to be found by modern technology than by traditional excavation. Aerial photography was the first such technology, and in fact the first archaeological aerial picture, taken in 1906, was of Stonehenge, so perhaps it’s fitting that modern techniques continue to turn up discoveries at the same site. After all, why spend time (and money) digging down for the past when you make images of it from the surface?
Written by Chris Gaffney : Senior Lecturer in Archaeological Geophysics at University of Bradford
The shape of living organisms evolves over a long period of time. The questions raised by this transformation have led to the emergence of theories of evolution. In order to research how biological shapes alter over a geological time scale, researchers have recently begun to investigate how they are generated during an individual’s development and growth; this is known as morphogenesis. Due to an exceptional diversity of their shell shapes and patterns (particularly the ribs), ammonites have been widely studied from the point of view of evolution but the mechanisms underlying the coiled spirals were unknown until now. Researchers therefore attempted to elucidate the evolution of these shapes without knowing how they had emerged.
Régis Chirat and his team have developed a model that explains the morphogenesis of these shells. By using mathematical equations to describe how the shell is secreted by ammonite and grows, they have demonstrated the existence of mechanical forces specific to developing mollusks. These forces are dependent upon the physical properties of the biological tissues and on the geometry of the shell. They cause mechanical oscillations at the edge of the shell that create ribs, a sort of ornamental pattern on the spiral.
Through examining various fossil specimens in light of the simulations produced by the model, the researchers observed that the latter could predict the number and shape of ribs in several ammonites. The model displays that the ornamentation of the shell evolves as a function of variables such as tissue elasticity and shell expansion rate (the rate at which the diameter of the opening increases with each spiral coil).
By providing a biophysical explanation for how these ornaments form, this theoretical approach explains the diversity existing within and between species. It thus opens new perspectives for the study of the morphological evolution of ammonites, which appears to be largely governed by mechanical and geometric constraints. This new tool unveils new information on an old mystery. For almost 200 million years, the shells of nautili, distant “cousins” of ammonites, have remained essentially smooth and free of distinctive ornamentation. The model shows that having maintained this shell shape does not mean that nautili- incorrectly referred to as “living fossils”- have not evolved, but this is due to a high expansion rate, leading to the formation of smooth shells that are difficult to distinguish from one another.
More generally, this work highlights the value of studying the physical bases of biological development: understanding the “construction rules” underlying the morphological diversity of organisms makes it possible to partially predict how their shape evolves.
Contributing Source: CNRS (Délégation Paris Michel-Ange)
Header Image Source: WikiPedia
James Williams, Director of Tosca & Willoughby said ‘we are absolutely fascinated by the discovery of a perfectly preserved ancient loo seat, as our own seats are handcrafted we admire the Roman craftsmanship which in this case has certainly stood the test of time’.
Mr Williams approached the Vindolanda Trust to help support the conservation of this seat when discovering the Vindolanda Trust was funded by visitors to the site. Mr Williams went on to say ‘we realise our donation is a drop in the ocean when you consider the overall cost of excavation and the preservation of these fascinating artefacts but we hope our continued pledges will help even in a small way towards the work of the Trust’. Tosca & Willoughby will be producing a special edition version of their most popular Thunderbox seat, with a percentage of the sales going to the Vindolanda Trust.
Patricia Birley, Director of the Vindolanda Trust commented ‘the work undertaken at Vindolanda which includes annual excavations, conservation and public display of artefacts can only happen with the support of the general public. The Trust is therefore delighted to receive a donation towards the cost of preserving our Roman toilet seat. The Romans were well known for their fine craftsmanship and it is great to see these traditions continue in the U.K with companies like Tosca & Willoughby’.
The discovery of such a personal everyday item from nearly 2000 years ago has intrigued people across the world and its legacy will now continue with a special edition ‘Vindolanda’ Thunderbox seat being launched by Tosca & Willoughby in time for the ancient loo seat going on public display.
While historical chronologies traditionally place the end of the Greek Bronze Age at around 1025 BCE, this latest research suggests a date 70 to 100 years earlier.
Archaeologists from the University of Birmingham selected 60 samples of animal bones, plant remains and building timbers, excavated at Assiros in northern Greece, to be radiocarbon dated and correlated with 95.4% accuracy using Bayesian statistical methodology at the University of Oxford and the Akademie der Wissenschaften Heidelberg, Germany.
The findings are published in the journal PLOS One.
Dr Ken Wardle of the Department of Classics, Ancient History and Archaeology at the University of Birmingham said: ‘These new results tell a story that is totally independent of and rather different from the conventional historical accounts of the date of the end of the Greek Bronze Age.
‘Until very recently the chronology of the later part of the Greek Bronze Age was entirely based on historical dates derived from Egypt and the Near East with the aid of exported or imported objects such as Minoan or Mycenaean pottery or Egyptian scarabs.
‘But if we accept the 14C radiocarbon dating – and there is no good reason not to – we have to rethink our understanding of a long sequence of dates from the middle of the 14th century BCE to the beginning of the 11th century BCE.
‘This is a fundamental reassessment and is important not just for Greece but in the wider Mediterranean context. It affects the ways in which we understand the relationships between different areas, including the hotly debated dates of developments in Israel and Spain.’
The dates derived from the samples meticulously excavated at Assiros – 25km from modern-day Thessaloniki – represent the most complete data set for the Greek Bronze Age, covering 400 years from the mid-14th century to the 10th century BCE. They tell a similar story to those determined for the volcanic eruption in Santorini (Thera), which has been re-dated from 1525 BCE to 1625 BCE as a result of scientific evidence.
Spectacular finds from ancient greek shipwreck: New Antihythera discoveries prove luxury cargo survives
The Antikythera wreck was first discovered back in 1900 by sponge divers who were blown off course by a storm. They subsequently recovered an outstanding haul of ancient treasures including bronze and marble statues, jewellery, furniture, luxury glassware, and the surprisingly complex Antikythera Mechanism. However, they were forced to end their mission prematurely at the 55-meter-deep site after one diver died of the bends and two were paralysed. Ever since, archaeologists have been left wondering if the site is home to even more treasure buried beneath the seabed.
Now a team of international archaeologists including Brendan Foley from the Woods Hole Oceanographic Institution and Theotokis Theodoulou from the Hellenic Ephorate of Underwater Antiquities have returned to the treacherous site, this time accompanied with state-of-the-art technology. During the first excavation season, taking place from September 15th to October 7th 2014, the researchers have created a high-resolution, 3D map of the site using stereo cameras mounted on an autonomous underwater vehicle (AUV). Divers proceeded to recover a series of finds that prove that much of the ship’s cargo is indeed still preserved beneath the sediment.
Components of the ship, including multiple lead anchors over a metre long and a bronze rigging ring with fragments of wood still attached, prove that a large proportion of the ship survives. The discoveries were also scattered over a much larger area than the sponge divers anticipated, covering 300 metres of the seafloor. This, along with the huge size of the anchors and recovered hull planks, proves that the Antikythera ship was much larger than previously thought, possibly up to 50 metres long.
“This evidence shows that this is the largest ancient shipwreck ever discovered,” says Foley. “It’s the Titanic of the ancient world.”
The archaeologists also recovered a beautiful intact table jug, part of an ornate bed leg, and most impressive of all the finds, a two-metre-long bronze spear buried just beneath the surface of the sand. It is too large and heavy to have been used as a weapon, therefore, it must have belonged to a giant statue, perhaps a warrior or the goddess Athena, says Foley. In 1901, four giant marble horses were discovered on the wreck by sponge divers, it is thought that these possibly formed a complex of statues involving a warrior in a chariot that was pulled by four horses.
The shipwreck dates from 70 to 60 BC and is thought to have been carrying a luxury cargo of Greek treasures from the coast of Asia Minor west to Rome. Antikythera is located in the middle of this major shipping route and the ship probably sank when a violent storm smashed it against the island’s sheer cliffs.
The wreck is too deep to dive safely with regular scuba equipment, so the divers had to use rebreather technology, in which carbon dioxide is scrubbed from the exhaled air while oxygen is introduced and recirculated. This enabled them to dive on the site for up to three hours at a time.
The archaeologists plan to return next year to excavate the site further and recover more of the ship’s precious cargo. The finds, particularly the bronze spear, are “very promising,” says Theodolou. “We have a lot of work to do at this site to uncover its secrets.”
Contributing Source: Woods Hole Oceanographic Institution
Header Image Source: Wikimedia
A comprehensive, English-language, open access encyclopedia of what was deemed the “Great War” was introduced and released on Wednesday 8th October, in Brussels. The project “1914-1918-online. International Encyclopedia of the First World War” is managed by researchers at Freie Universität Berlin in cooperation with the Bavarian State Library. It is funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG). The encyclopaedia combines the latest historical research with the many advantages of the Semantic Web. The content was written and compiled by 1,000 experts from 54 countries, and is continuously being updated and expanded.
This year marks the centenary of World War I, which is considered to be the “great seminal catastrophe of the twentieth century”. This anniversary is an important reference point for the creation of a transitional and global historical consciousness, offering a chance to discuss the roots of and possibilities for European integration.
The online encyclopaedia “1914-1918-online” provides a comprehensive description of the “Great War” from a pan-European and global perspective. It is a user-friendly and easily allocable digital work resource. Prof. Dr. Oliver Janz, a historian at the Friedrich Meinecke Institute of Freie Universität de Berlin, along with Prof. Dr. Nicholas Apostolopoulos, the director of the Centre for Digital Systems, Freie Universität de Berlin have led the project.
The online encyclopaedia was presented during a meeting called “World War One goes World Wide Web- 1914-1918-online.” The meeting was jointly organised by the Berlin Senate Chancellery, the European minister in North Rhine-Westphalia, Freie Universität Berlin, and the Committee of the Regions, which also functioned as a host. The meeting received financial support from the German Foreign Office and Allianz SE, a German insurance and financial services company.
Contributing Source: Freie Universität Berlin
Header Image Source: Wikimedia
Bronze Age Palace and Grave Goods Discovered at the Archaeological Site of La Almoloya in Pliego, Murcia
La Almoloya resides on a steep plateau, one that dominated an extensive region. This both strategic and privileged position allowed over six centuries of occupation, from 2200 to 1550 before our common era. Emeterio Cuadrado and Juan de la Cierva discovered the site back in 1944.
The findings indicate that La Almoloya functioned as a primary centre of politics and wealth within the political territory of El Argar- located a few hundred kilometres to the south in Almeria- and unveils new information on the politics and gender relations in one of the first urban societies of the West.A Palatial Building and new Argaric Style
The discoveries made by the archaeological team include an urban tissue made up of fully equipped buildings, along with dozens of tombs, most of which included grave goods. According to archaeologists, this urban tissue, as well as the solidity and mastery of the construction techniques, are unique samples of prehistoric constructions in continental Europe.
The excavations demonstrate that the La Almoloya plateau, of 3,800 metres square, was densely populated and included several residential complexes of some 300 square metres, with eight to twelve rooms occupying each residence.
The building’s walls were constructed with stones and argamasa, and covered with layers of mortar. Some parts contain stucco decorated with geometric and naturalistic motifs, a novelty which represents the discovery of an Argan artistic style.
Among the discoveries made is a wide hall with high ceilings measuring 70 square metres, with a capacity for 64 people seated on the benches lining the walls. The hall contains a ceremonial fireplace and a podium of symbolic character. This unique building was used for political purposes and archaeologists think that it must have been used to celebrate hearings or government meetings.
Archaeologists confirm that this is the first time a building specifically dedicated to governing purposes has been discovered in Western Europe, and are believe that decisions were made here which impacted many of the region’s other communities.
The hall and adjoining rooms make up a large building, which the archaeologists have classified as a palace. They highlight the fact that only the most important Oriental civilisations had similar constructions during the Bronze Age, with comparable structures and functions.A Princely Tomb with Objects of Great Value
Of the fifty tombs excavated from under the La Almoloya buildings, one stands out in particular. Located in a privileged area, next to the main wall of the hall, the tomb exposes the remains of a man and a woman buried with their bodies in a flexed position and accompanied by thirty objects containing precious metals and semi-precious stones.
One of the most exceptional pieces is a silver diadem that encircled the skull of the woman. The silver diadem is of great scientific and patrimonial value, since the only other four diadems known to have existed were all discovered 130 years ago at the site of El Agar in Almeria, but none remain today in Spain.
Four ear dilators, which are unusual objects for the Bronze Age, were also discovered; two are made up of solid gold and two of silver.
The wealth of silver found at the site is especially notable, since archaeologists also discovered nine other objects made of silver, including rings, earrings and bracelets. They also discovered that the nails used to hold the handle of an elaborate bronze dagger were made of silver.
One of the most admirable items is a small ceramic cup with the rim and outer part covered in fine layers of silver, which constitutes a pioneering example of silverwork on vessels.
The last item worth mentioning is a metallic punch with bronze tip and a handle forged in silver. Archaeologists were in awe of the perfection with which the cup was crafted and the grooved designs which decorate the top of the punch.
According to researchers, the artefacts discovered at La Almoloya are of great historical and patrimonial relevance. Their interest transcends local sale and should be considered of first order for all of Europe. They assure that the items are unique and that in addition to their intrinsic value, there is also the fact that they are perfectly contextualised. The archaeologists also stress the need to conserve, study and publicise these findings.
La Almoloya contains many unknown answers and offers a vast amount of promising perspectives for future digs. The completion of the urban tissue and revealing the details of the first political structure of the West are some of the challenges remaining, archaeologists conclude.A team expert in the Argaric Culture
The team leading the archaeological dig at La Almoloya is led by Vicente Lull, Rafael Micó, Cristina Rihuete and Roberto Risch, professors at the Universitat Autònoma de Barcelona.
The same team had previously made crucial discoveries at the La Bastida site, another dig site in Murcia from the Bronze Age. From 2008-2012 the team was also able to unveil a large fortification and several constructions discovered in the Argaric city.
The digs carried out at La Almoloya received funding from the firm CEFU, SA, owner of the land on which the site is located, and from Universitat Autònoma de Barcelona. The Council of Education, Culture and Universities of the Region or Murcia also have offered support to the research.
Contributing Source: Universitat Autònoma de Barcelona
Header Image Source: Wikimedia
For a long time scientists have used DNA data to develop molecular clocks that measure the rate at which DNA changes, i.e. accumulates mutations, as a premier tool to delve into the past evolutionary timelines for the lineage of a given species. For example, in human evolution molecular clocks, when combined with fossil evidence, have aided in tracing the time of the last common ancestor of chimpanzees and humans to 5-7 million years ago, and contributed to the recent ‘out of Africa’ theory for a great human migration event 100,000 years ago.
In order to improve the modelling and reading of the branches on the human tree of life, authors Francois Balloux et al, compiled the most comprehensive DNA set to date, a new treasure trove of 146 ancient (including Neanderthal and Denisovian) and modern human full mitochondrial genomes (amongst a set of 320 available worldwide). Mitochondrial DNA (mtDNA) is a valuable resource for evolutionary scientists, because they have a high mutation rate, and unlike genomic DNA, are only inherited maternally.
Now, by using a variety of sophisticated calibration techniques, the authors have improved the accuracy of using mtDNA as a molecular clock by recalibrating the human evolutionary tree. They demonstrated that a molecular clock calibrated with ancient sequences was much more accurate that the traditional ones based on archaeological evidence. With this new recalibration, scientists are now able to trace back, with greater accuracy than ever before, the first ‘Eves’ of the many migrations leading to the colonisation of the earth by anatomically modern humans.
“The recent possibility to generate high-quality genome sequences from ancient remains represents an amazing progress in our ability to accurately reconstruct the past history of many species, including our own,” said author Adrien Rieux.
The research has been published this week in Molecular Biology and Evolution.
Contributing Source: Molecular Biology and Evolution (Oxford University Press)
Header Image Source: Wikimedia
“The genome and the information it contains about our ancestry and evolution is huge,” says lead author Mark Statham, an assistant project scientist with the UC Davis Veterinary Genetics Laboratory. “If you’re only looking at what your mother’s mother’s mother did, you’re only getting a small proportion of the story.”
The study has been published in the latest issue of the journal Molecular Ecology and represents the most globally comprehensive work yet to be conducted on the red fox.
Conventional thinking based on maternal genetics implied that red foxes from Eurasia and North America composed a single interconnected population across the Bering land bridge between Asia and Alaska. To contrast with this however, this new research indicates that the red foxes of North America and Eurasia have been almost entirely reproductively isolated from one another for approximately 400,00 years. During this time, the North American red fox evolved into a new species distinct from its Old World ancestors.
The previous view was misleading by the maternal picture because a single female line transferred from Asia to Alaska about 50,000 years ago.
The novel genetic research further suggests that the first red foxed originally came from the Middle East before beginning their journey of colonisation across Eurasia to Siberia, across the Bering Strait and into North America, where they eventually founded the North American population.
“That small group that got across the Bering Strait went on to colonise a whole continent and are on their own evolutionary path,” Statham said.
During the red foxes’ journey over millennia, ice sheet formation and fluctuating temperatures and sea levels offered periods of isolation and reconnection, impacting on their global distribution. Statham has said that understanding the evolutionary history of the red fox will allow an insight into how other species might have responded to climate change and those same environmental shifts.
The research effort, headed by Statham and Ben Sacks, associate adjunct professor and director of the UC Davis Mammalian Ecology and Conservation Unit, included a network of collaborators and contributors from around the globe and relied heavily on specimens in natural history museums.
The study received primary funding from the Systematic Research Fund through the Systematics Association of the Linnean Society of London and the Veterinary Genetics Laboratory at UC Davis.
Contributing Source: UC Davis
Header Image Source: Flickr
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