Barbequed clams on the menu for ancient Puerto Ricans

By: Thomas Schmitt Attorney on November 27, 2019 / comment : 0 Americas, Archaeology, Puerto Rico, South America

Scientists have reconstructed the cooking techniques of the early inhabitants of Puerto Rico by analysing the remains of clams.

Photographs of all shells analyzed in this study [Credit: Cardiff University]

Led by Philip Staudigel, who conducted the analysis as a graduate student at the University of Miami Rosenstiel School and is now a postdoctoral researcher at Cardiff University, the team has used new chemical analysis techniques to identify the exact cooking temperatures at which clams were cooked over 2500 years ago.

With cooking temperatures getting up to around 200oC according to the new analysis, the team believe the early Puerto Ricans were partial to a barbeque rather than boiling their food as a soup.

The study, which also involved academics from the University of Miami and Valencia College, has been published today in the journal Science Advances.

Whilst the results throw new light on the cultural practices of the first communities to arrive on the island of Puerto Rico, they also provide at least circumstantial evidence that ceramic pottery technology was not widespread during this period of history - it's likely that this would be the only way in which the clams could have been boiled.

Lead author of the study Dr Philip Staudigel, currently at Cardiff University's School of Earth and Ocean Sciences, said: "Much of peoples' identity draws upon on where they came from, one of the most profound expressions of this is in cooking. We learn to cook from our parents, who learned from their parents.

Measuring in excavation unit at CRNWR_P13 [Credit: Carlos Mora]

"In many parts of the world, written records extend back thousands of years, which often includes recipes. This is not the case in the Caribbean, as there were no written texts, except for petroglyphs. By learning more about how ancient Puerto Rican natives cooked their meals, we can relate to these long-gone peoples through their food."

In their study, the team analysed over 20kg of fossilised clam shells at the University of Miami's Rosenstiel School of Marine and Atmospheric Sciences Stable Isotope Lab, which were collected from an archaeological site in Cabo Rojo, Puerto Rico.

The pre-Arawak population of Puerto Rico were the first inhabitants of the island, arriving sometime before 3000 BC, and came from Central and/or South America. They existed primarily from fishing, hunting, and gathering near the mangrove swamps and coastal areas where they had settled.

The fossilised shells, dating back to around 700 BC, were cleaned and turned into a powder, which was then analysed to determine its mineralogy, as well as the abundance of specific chemical bonds in the sample.

When certain minerals are heated, the bonds between atoms in the mineral can rearrange themselves, which can then be measured in the lab. The amount of rearrangement is proportional to the temperature the mineral is heated.

Sample reacting with phosphoric acid, releasing CO2 gas which will then be analyzed using mass spectrometry [Credit: Philip Staudigel]

This technique, known as clumped isotope geochemistry, is often used to determine the temperature an organism formed at but in this instance was used to reconstruct the temperature at which the clams were cooked.

The abundance of bonds in the powdered fossils was then compared to clams which were cooked at known temperatures, as well as uncooked modern clams collected from a nearby beach.

Results showed that that the majority of clams were heated to temperatures greater than 100°C - the boiling point of water - but no greater than 200°C. The results also revealed a disparity between the cooking temperature of different clams, which the researchers believe could be associated with a grilling technique in which the clams are heated from below, meaning the ones at the bottom were heated more than the ones at the top.

"The clams from the archaeological site appeared to be most similar to clams which had been barbequed," continued Dr Staudigel.

"Ancient Puerto Ricans didn't use cookbooks, at least none that lasted to the present day. The only way we have of knowing how our ancestors cooked is to study what they left behind. Here, we demonstrated that a relatively new technique can be used to learn what temperature they cooked at, which is one important detail of the cooking process."

Source: Cardiff University [November 27, 2019]

5,000-year-old pyramid-like structure found in northern Peru

By: Thomas Schmitt Attorney on November 21, 2019 / comment : 0 Americas, Archaeology, Peru, South America

A pyramid-like structure at least 5,000 years old, allegedly devoted to ceremonial purposes, was unveiled thanks to excavation works conducted at Sechin archaeological complex in Casma Province of Ancash Region in northern Peru.

Credit: Andina

It is a stepped structure, at least 3.20 metres high and 5 metres wide. Sechin Archaeological Project archaeologists and workers had to excavate some 6 metres of soil and remove stones in order to unearth it.

Archaeologist Monica Suarez, coordinator at Sechin Archaeological Project, commented that the pyramid is located within the south-central part of the main building. It is believed that it was used for ceremonial purposes.

Credit: Andina

"It is of great importance in these ceremonial sites. It served a ceremonial purpose, but we need to make further analysis (…)," she said in statements to Andina news agency.

Additionally, the team of researchers discovered two skulls —one of an adult and one of a child— and a dismembered body on the side, which makes the theory of ceremonial practices gain traction.

Credit: Andina

The researcher stressed the possibility that the stepped, pyramid-shaped structure served as a ladder to get to a higher level.

"There is an adobe wall at the top, with fingerprints of Sechin inhabitants visible in the mud. They are believed to be a symbol of their work," she said.

Source: Andina [November 21, 2019]

Infants wearing ‘helmets’ made from skulls of other children unearthed in Ecuador

By: Thomas Schmitt Attorney on November 20, 2019 / comment : 0 Americas, Archaeology, Ecuador, South America

Two infants were buried more than 2,000 years ago wearing strange “helmets” made from the skulls of other children, researchers found.

The researchers found a small shell and a finger bone sandwiched between the two layered skulls [Credit: Sara Juengst/UNC Charlotte]

Scientists, led by study co-author Sara Juengst at the University of North Carolina’s department of anthropology, discovered the remains at a site called Salango, in Ecuador and published their findings recently in the journal Latin American Antiquity.

The researchers believe this is the only known instance of children’s skulls being used as helmets for the burial of infants and they don’t know what killed the infants and children.

Archaeologists unearthed 11 burials in South America, two of which were infants with 'helmets' made from the skulls of other children [Credit: Sara Juengst/UNC Charlotte]

One infant’s face “looked through and out of the cranial vault” — the space that holds the brain — Sara Juengst noted.

The sciencists report that a “hand phalanx,” which is a type of hand bone, was found between the infant’s head and the helmet. Researchers reportedly don’t know whose hand was involved.

Lesions were found on the remains of both of the infants (a and d), suggesting they had suffered some kind of bodily stress. Experts suggest they may have been sacrificed or suffered from malnutrition [Credit: Sara Juengst/UNC Charlotte]

The archaeologists also noted that it’s probable that the children’s skulls had flesh on them when they were turned into helmets, because the helmets likely would not have held together without flesh.

Juengst was joined by a colleague at UNC, along with scientists from Yale University and Universidad Tecnica de Manabi, in reporting on these findings.

Author: Christopher Carbone | Source: Fox News [November 20, 2019]

New fossils shed light on how snakes got their bite and lost their legs

By: Thomas Schmitt Attorney on November 20, 2019 / comment : 0 Australia, Fossils, Palaeontology, South America

New fossils of an ancient legged snake, called Najash, shed light on the origin of the slithering reptiles.

Lifelike rendition of Najash [Credit: Raul O. Gomez, Universidad de Buenos Aires]

The fossil discoveries published in Science Advances have revealed they possessed hind legs during the first 70 million years of their evolution. They also provide details about how the flexible skull of snakes evolved from their lizard ancestors.

The evolution of the snake body has captivated researchers for a long time - representing one of the most dramatic examples of the vertebrate body's ability to adapt - but a limited fossil record has obscured our understanding of their early evolution until now.

Dr Alessandro Palci, from Flinders University, was part of the international research team that performed high-resolution (CT) scanning and light microscopy of the preserved skulls of Najash to reveal substantial new anatomical data on the early evolution of snakes.

Najash specimens from LBPA [Credit: Garberoglio et al. 2019]

"Snakes are famously legless, but then so are many lizards. What truly sets snakes apart is their highly mobile skull, which allows them to swallow large prey items. For a long time we have been lacking detailed information about the transition from the relatively rigid skull of a lizard to the super flexible skull of snakes".

"Najash has the most complete, three-dimensionally preserved skull of any ancient snake, and this is providing an amazing amount of new information on how the head of snakes evolved. It has some, but not all of the flexible joints found in the skull of modern snakes. Its middle ear is intermediate between that of lizards and living snakes, and unlike all living snakes it retains a well-developed cheekbone, which again is reminiscent of that of lizards."

Flinders University and South Australian Museum researcher Professor Mike Lee, was also part of the study, and adds "Najash shows how snakes evolved from lizards in incremental evolutionary steps, just like Darwin predicted."

CT scan reconstructions of the articulated skull of Najash [Credit: Garberoglio et al. 2019]

The new snake family tree also reveals that snakes possessed small but perfectly formed hind legs for the first 70 million years of their evolution.

"These primitive snakes with little legs weren't just a transient evolutionary stage on the way to something better. Rather, they had a highly successful body plan that persisted across many millions of years, and diversified into a range of terrestrial, burowing and aquatic niches," says Professor Lee.

Source: Flinders University [November 20, 2019]

143 new Nazca geoglyphs discovered

By: Thomas Schmitt Attorney on November 19, 2019 / comment : 0 Americas, Archaeology, Peru, South America

Located in the Nazca Desert in southern Peru, the Nazca Lines are a collection of giant etchings that only make sense from a great height. Now AI is helping speed up the hunt for more hidden symbols -  and has already had some success.

A newly discovered geoglyph, left, in Peru's Nazca Lines has human form. The image, right, offers a clearer picture of what it depicts. The black rule at the bottom of the photo shows it is 4 meters wide [Credit: Yamagata University]

Since their discovery in the 1920s, the Nazca Lines have continued to mystify experts. Created between 200 BCE and 600 CE, they were made by removing stones to reveal the white sand beneath and depict various geometric shapes, people, and animals, known as geoglyphs. In 1994 they were designated a UNESCO World Heritage Site, but their purpose and meaning have continued to elude historians.

In 2004, a team led by Masato Sakai at Yamagata University in Japan began a concerted effort to map out all the lines in the hopes of preserving them and understanding their significance. Through over a decade of fieldwork and the analysis of high-resolution 3D data, the team has uncovered 142 new designs, it announced this week.

A geoglypth of a human figure, left, was discovered using AI technology. The image, right,  gives a clearer of idea of its shape [Credit: Yamagata University]

A geoglyph of what appears to be rat with a human figure on the right side [Credit: Yamagata University]

A cat-like geoglyph [Credit: Yamagata University]

The geoglyphs fall into two main categories. Larger animal-like designs, as long as 100 meters (330 feet), were likely used to demarcate places of ritual. Smaller symbols, some smaller than 5 meters (16 feet), probably served as waypoints for travelers.

This geoglyph is thought to depict a human [Credit: Yamagata University]

This image appears to be a two-headed snake feasting on humans [Credit: Yamagata University]

A geoglyph of what appears to be a human head headdress [Credit: Yamagata University]

There are many more etchings waiting to be discovered, but the process of finding them has become harder. Many of the lines have been damaged by floods, roads, and urban expansion. The researchers believe they also span a far larger area than previously imagined, which would take significantly more time to search using traditional methods.

This geoglyph is thought to depict a bird [Credit: Yamagata University]

This geoglyph appears to depict a human with animals [Credit: Yamagata University]

This geoglyph appears to depict someone wearing a headdress [Credit: Yamagata University]

In a collaboration with IBM Research, the team is now deploying deep-learning algorithms to help speed up the hunt. The researchers are using a cloud platform to stitch together massive amounts of geospatial data, including lidar, drone, and satellite imagery and geographical surveys, to create high-fidelity maps of the search areas.


They are then training a neural network to recognize the data patterns of known lines to look for new ones. Even during testing, the team discovered a new design - a smaller humanoid figure - that had been missed in previously collected data. The discovery took only two months; previous methods had typically taken years.

Source: MIT Tehnology Review [November 19, 2019]

3,000-year-old megalithic temple found in Peru

By: Thomas Schmitt Attorney on November 14, 2019 / comment : 0 Americas, Archaeology, Peru, South America

A 3,000-year-old megalithic 'water cult' temple used for fertility rituals has been discovered in Peru by a team of Peruvian archaeologists.

Aerial view of the El Toro excavation site, where remains of a 3,000-year-old megalithic temple were discovered in Oyotun, Chiclayo province, Labayeque department, Peru [Credit: AFP]

The religious monument is over 131ft long and is located in the springs of the Zana Valley river about 500miles from Lima, the modern capital of Peru.

Inside the temple archaeologists found a square with an altar that was likely used to offer important fertility rituals with water taken from the Zana Valley river.

The temple is located in what is called the tinkuy, that is, the union of two rivers that were sacred spaces in ancient cultures: the Nanchoc and Udima rivers to form the Zana [Credit: RPP News]

The religious monument is over 131ft long and includes the remains of large stone blocks and a central staircase

The megalith structure was found at the Huaca El Toro site in the Lambayeque region of Peru by a team led by Walter Alva, the archaeologist who discovered the tomb of the Lord of Sipan in 1987.

It is the only megalithic structure that exists in the Lambayeque region. The facade and all the side walls were built with large granite blocks [Credit: RPP News]

The temple still features the remains of large stone blocks and a long staircase. "This discovery is unique because it is the only megalithic architecture in Lambayeque," said Dr Alva.

The site was discovered in October but the news of its finding was delayed to reduce the risk of treasure hunters taking artefacts that hadn't been secured.

A staircase at the El Toro excavation site [Credit: RPP News]

Archaeologists from Peru, seen here, found stunning walls surrounding the monument as well as a central altar likely used for fertility rituals.

The megalith structure was found at the Huaca El Toro site in the Lambayeque region of Peru by a team led by Walter Alva, the archaeologist who discovered the tomb of the Lord of Sipan in 1987.

The graves date to after the temple was abandoned indicating that it was used by the Chimus as a burial ground [Credit: RPP News]

The temple comes from a time when water was considered divine and was used in a number of rituals and religious practices, researchers claim. They were able to determine this temple was home to a cult that worshipped water by studying the way the altar is positioned and how it looks. The altar includes holes similar to those found on other temples from the period.

"This is typical of water altars that are in other places, and it is located in the springs of the Zana Valley river", Mr Alva said.

Some 21 burials were found at the temple [Credit: RPP News]

The temple was discovered by Walter Alva - pictured - who also discovered the tomb of the Lord of Sipan in 1987 in northern Peru.

Scientists found metal and ceramic objects in the graves discovered on the site, however most of the graves date from the later Inca period. They found a staircase on the site that was 32ft wide and 49ft long

Some of the vessels placed as offerings in the graves [Credit: RPP News]

Mr Alva said they have identified a circular column, where evidence of sedimentation of rains and rituals was found. 'This temple is facing the mountain. This place is strictly ceremonial because of the signs of burning that took place. The rituals were performed for fertility,' he said.

Stunning walls surround the monument and there is a central staircase that is 32ft wide and 49ft long.

Peruvian archaeologist Walter Alva pointing to excavations  at the site of El Toro [Credit: AFP]

The Peruvian team discovered 21 tombs on the site of the temple which is thought to date back to about 1,500 BC to 292 AD. Inside the tombs they found ceramic pieces and metal objects such as knives that were placed next to the graves.

Mr Alva says it is likely the tombs were later re-used as 20 of burial sites were from the later Inca Chimu culture which dates back to about 1,000 to 1,470 AD.

Some of the huge blocks have petroglyphs suggesting that they were brought  from a sacred place [Credit: RPP News]

This isn’t the first major discovery made by Walter Alva and his team. The archaeologist also discovered the tomb of the Lord of Sipan in 1987. Sipan was a ruler of Mochica culture and his remains were found intact in Northern Peru.

In 2007 he discovered a number of 4,000-year-old murals in Peru. They show a deer caught in a net and are thought to be the oldest murals in the Americas.

Author: Ryan Morrison | Source: Daily Mail [November 14, 2019]

Oldest carnivorous dinosaur unearthed in southern Brazil

By: Thomas Schmitt Attorney on November 12, 2019 / comment : 0 Brazil, Dinosaurs, Fossils, Palaeontology, South America

An amazingly well-preserved skeleton of the world's oldest-known meat-eating dinosaur has been unearthed in the south of Brazil.

Illustration of Gnathovorax cabreirai [Credit: Marcio L. Castro]

The predator named 'Gnathovorax cabreirai' lived 230 million years ago when South America was still part of the supercontinent called Pangaea.

The skeleton is virtually intact — and includes razor-sharp teeth and claws that would have made it a ferocious killer. Its genus name means 'ravenous jaws'.

Experts were even able to reconstruct the dinosaur's brain — showing that it would have had good eyesight and co-ordination.

This would have made it an 'apex predator' which sat at the top of the food chain, said biologist Rodrigo Muller of Brazil's Federal University of Santa Maria.

The remarkable discovery may even help researchers better understand the evolution of T Rex, one of Gnathovorax's distant ancestors.

In life, Gnathovorax would have stood at around 10 feet (3 metres) in length and likely weighed as much as half a ton.

The rock block with the fossil was discovered in 2014 in Sao Joao do Polesine by paleontologist Sergio  Furtado Cabreira [Credit: Universidade Federal de Santa Maria, Rodrigo Temp Muller]

According to the researchers, it is the oldest-known carnivorous dinosaur by about 30 million years.

Dinosaurs ruled the Earth for most of the so-called Mesozoic Era — between around 250–65 million years ago.

However, most of the 'super predators' like Tyrannosaurus rex and Allosaurus lived over tens of millions of years later than Gnathovorax, during the Jurassic and Cretaceous Periods.

'The oldest predatory dinosaurs — that lived during the Triassic around 230 million years before the present — are, however, still rare findings,' said Dr Muller.

'Gnathovorax cabreirai is represented by an almost complete skeleton excavated in southern Brazil.'

'The beast measured about three meters in length and is one of the oldest dinosaurs in the world.'

Illustration of Gnathovorax cabreirai in life, along with fantosaurs, in a graphic recreation by paleoartist  Marcio Castro [Credit: Universidade Federal de Santa Maria]

'Moreover, it was one of the largest carnivores of its area 230 million years ago — much before its larger cousins from [the] Jurassic and Cretaceous.'

The only other known dinosaurs to date back to this time period were less than twice the size of Gnathovorax — barely reaching five feet (1.5 metres) in length.

These include a plant-eating sauropod — dubbed Buriolestes schultz — which was unearthed from a nearby fossil site three years ago.

Gnathovorax was one of the original beast-footed (theropod) dinosaurs that would eventually give rise to T Rex.

'The outstanding skeleton possesses sharp teeth and claws, which may have been used by Gnathovorax to capture its prey,' said Dr Muller.

(A) Right lateral view. (B) Three-dimensional rendering of the skull in right lateral view. (C) Three-dimensional rendering  of the skull in left/dorsal lateral view. (D) Schematic drawing in right lateral view. an, angular; anf, antorbital fenestra;  d, dentary; emf, external mandibular fenestra; en, external naris; j, jugal; l, lacrimal; m, maxilla; n, nasal; of, oval  fenestra; p, parietal; pm, premaxilla; prf, prefrontal; pt, pterygoid; q, quadrate; qj, quadratojugal; sa, surangular;  snf, subnarial foramen; sq, squamosal; stf, supratemporal fenestra [Credit: Cristian Pacheco et al. 2019]

'Additionally, the exquisitely preserved skeleton allowed us to reconstruct the shape of the brain of the animal.'

Using a CT scanner — like those found in hospitals — researchers were able to examine the skull's interior, shedding light on Gnathovorax's faculties.

'The effort revealed features shared with other predators, including well-developed areas related to visual coordination and balance,' Dr Muller added.

'This combination of assets indicate that the new dinosaur was an active predator of its time.'

The researchers have referenced this in their naming of the new species, with 'Gnathovorax' meaning 'ravenous jaws'.

Meanwhile, the species name — 'cabreirai' — 'honours palaeontologist Dr Sergio Furtado Cabreira who made the discovery while excavating near the city of Santa Maria in the state of Rio Grande do Sul,' explained Dr Muller.

(A) Strict consensus tree depicting the phylogenetic position of Gnathovorax cabreirai (numbers represent Bremer  support values higher than 1). (B) Bivariate plot showing the result of the morphological disparity analysis. Green  convex hull corresponds to morphospace of sauropodomorphs, blue convex hull corresponds to morphospace  of ornithischians, yellow convex hull corresponds to morphospace of theropods, purple convex hull corresponds  to morphospace of herrerasaurids, and ‘X’, are other archosaurs. (C) Geochronological distribution of  herrerasaurids, sauropodomorphs, and theropods. Note: silhouettes are composites  from different sources [Credit: Cristian Pacheco et al. 2019]

'[Our] analysis places the new dinosaur closely related to Herrerasauridae, a group of predatory dinosaurs known from Argentina and Brazil,' said Dr Muller.

These early hunting dinosaurs first roamed the Earth around 233 million years ago — and died out around 30 million years later.

'The new skeleton is, however, the most complete single individual ever discovered for the group.'

The only other herrerasaur known from Brazil — dubbed 'Staurikosaurus pricei' — is represented only by an incomplete skeleton recovered back in 1936, more than eight decades ago.

'Much information has been already gathered about the largest predatory dinosaurs from the Jurassic and Cretaceous Periods,' added paper author and palaeontologist Cristian Pereira Pacheco, also of the Federal University of Santa Maria.


However, he added, 'their early evolutionary history is still poorly understood, given the scarcity of fossils.'

'Here, we describe Gnathovorax cabreirai, a new herrerasaurid based on an exquisite specimen found in southern Brazil.'

'Given its superb state of preservation and completeness, the new specimen sheds light into poorly understood aspects of the herrerasaurid anatomy - including soft tissues.'

The full findings of the study were published in the journal PeerJ.

Author: Ian Randall | Source: Daily Mail Online [November 12, 2019]

Evolutionary diversity is associated with Amazon forest productivity

By: Thomas Schmitt Attorney on November 11, 2019 / comment : 0 Biodiversity, Ecosystems, Evolution, Genetics, Rainforests, South America

An international team of researchers led by the University of Leeds have revealed for the first time that Amazon forests with the greatest evolutionary diversity are the most productive.

The Amazon canopy [Credit: Fernanda Coelho,  University of Leeds]

The team used long term-records from 90 plots as part of the Amazon Forest Inventory Network (RAINFOR) and ForestPlots.net to track the lives and productivity of individual trees across the Amazon region. By combining these records with DNA sequence data - which identified the evolutionary relationships among all the species - the team was able to investigate the links between how fast different forests grow and their diversity.

Their study demonstrated that the plots with the greatest evolutionary diversity were a third more productive compared to areas with the least evolutionary diversity.

The finding suggest that evolutionary diversity should be an important consideration when identifying priority areas for conservation.

Study lead author Fernanda Coelho from the School of Geography at Leeds said: "Understanding how biodiversity affects productivity in tropical forests is important because it allows us to understand how conservation strategies can best be designed to maximise protection of species and the services that these ecosystems provide.

"Our results indicate that we should include evolutionary history in conservation priorities - because ecosystem function may be higher in areas where species come from right across the tree of life'.

The paper is published in Nature Ecology & Evolution.

Source: University of Leeds [November 11, 2019]

Human activities drying out the Amazon: NASA study

By: Thomas Schmitt Attorney on November 06, 2019 / comment : 0 Amazonia, Biodiversity, Brazil, Ecosystems, Environment, Natural Heritage, Rainforests, South America

A new NASA study shows that over the last 20 years, the atmosphere above the Amazon rainforest has been drying out, increasing the demand for water and leaving ecosystems vulnerable to fires and drought. It also shows that this increase in dryness is primarily the result of human activities.

The Amazon rainforest [Credit: Marcio Isensee e Sa/Adobe Stock]

Scientists at NASA's Jet Propulsion Laboratory in Pasadena, California, analyzed decades of ground and satellite data over the Amazon rainforest to track both how much moisture was in the atmosphere and how much moisture was needed to maintain the rainforest system.

"We observed that in the last two decades, there has been a significant increase in dryness in the atmosphere as well as in the atmospheric demand for water above the rainforest," said JPL's Armineh Barkhordarian, lead author of the study. "In comparing this trend to data from models that estimate climate variability over thousands of years, we determined that the change in atmospheric aridity is well beyond what would be expected from natural climate variability."

So if it's not natural, what's causing it?

Barkhordarian said that elevated greenhouse gas levels are responsible for approximately half of the increased aridity. The rest is the result of ongoing human activity, most significantly, the burning of forests to clear land for agriculture and grazing. The combination of these activities is causing the Amazon's climate to warm.

When a forest burns, it releases particles called aerosols into the atmosphere—among them, black carbon, commonly referred to as soot. While bright-colored or translucent aerosols reflect radiation, darker aerosols absorb it. When the black carbon absorbs heat from the sun, it causes the atmosphere to warm; it can also interfere with cloud formation and, consequently, rainfall.

Why It Matters

The Amazon is the largest rainforest on Earth. When healthy, it absorbs billions of tons of carbon dioxide (CO2) a year through photosynthesis—the process plants use to convert CO2, energy and water into food. By removing CO2 from the atmosphere, the Amazon helps to keep temperatures down and regulate climate. But it's a delicate system that's highly sensitive to drying and warming trends.

The image shows the decline of moisture in the air over the Amazon rainforest, particularly across the south  and southeastern Amazon, during the dry season months - August through October - from 1987 to 2016. The measurements are shown in millibars [Credit: NASA/JPL-Caltech, NASA Earth Observatory]

Trees and plants need water for photosynthesis and to cool themselves down when they get too warm. They pull in water from the soil through their roots and release water vapor through pores on their leaves into the atmosphere, where it cools the air and eventually rises to form clouds. The clouds produce rain that replenishes the water in the soil, allowing the cycle to continue. Rainforests generate as much as 80% of their own rain, especially during the dry season.

But when this cycle is disrupted by an increase in dry air, for instance, a new cycle is set into motion—one with significant implications, particularly in the southeastern Amazon, where trees can experience more than four to five months of dry season.

"It's a matter of supply and demand. With the increase in temperature and drying of the air above the trees, the trees need to transpire to cool themselves and to add more water vapor into the atmosphere. But the soil doesn't have extra water for the trees to pull in," said JPL's Sassan Saatchi, co-author of the study. "Our study shows that the demand is increasing, the supply is decreasing and if this continues, the forest may no longer be able to sustain itself."

Scientists observed that the most significant and systematic drying of the atmosphere is in the southeast region, where the bulk of deforestation and agricultural expansion is happening. But they also found episodic drying in the northwest Amazon, an area that typically has no dry season. Normally always wet, the northwest has suffered severe droughts over the past two decades, a further indication of the entire forest's vulnerability to increasing temperatures and dry air.

If this trend continues over the long term and the rainforest reaches the point where it can no longer function properly, many of the trees and the species that live within the rainforest ecosystem may not be able to survive. As the trees die, particularly the larger and older ones, they release CO2 into the atmosphere; and the fewer trees there are, the less CO2 the Amazon region would be able to absorb—meaning we'd essentially lose an important element of climate regulation.

The study was published in Scientific Reports.

Author: Esprit Smith | Source: NASA [November 06, 2019]

Fifteen pre-Hispanic burials discovered in Colombia

By: Thomas Schmitt Attorney on November 05, 2019 / comment : 0 Americas, Archaeology, Colombia, South America

Archaeologists have uncovered 15 burials with the remains of a pre-Hispanic indigenous community on the grounds of the Pedagogical and Technological University of Colombia (UPTC) located in the city of Tunja in Northern Colombia.

Credit: UPTC - Universidad Pedagógica y Tecnológica de Colombia

The burials, which are believed to date back over 500 years, were found approximately 50 centimetres deep over an area of 1,500 square metres on the University grounds. About 500 kg of ceramic and lithic remains were also recovered at the site.

Credit: UPTC - Universidad Pedagógica y Tecnológica de Colombia

According to archaeologists, the characteristics of the findings suggest the remains belong to the Muisca people, who occupied the Andean Highland region of Colombia prior to the arrival of the Spaniards in 1537. There is a population of around 14,000 indigenous Muiscans still living in present-day Colombia.

Credit: UPTC - Universidad Pedagógica y Tecnológica de Colombia

Anthropologist working on the site Fabian Alvarez said: “We have the footprints, the vestiges of the footprints of the house and the graves of the people who probably lived here. Once we have cleaned and classified all these findings, they will help us answer a lot of questions.”


The findings will be given to the UPTC’s forensic laboratory, where they will be analysed for scientific purposes.

Source: UPTC - Universidad Pedagógica y Tecnológica de Colombia [November 05, 2019]