All posts by Archaeology World Team

ASIA, JAPAN, WORLD

Japanese scientists ‘reawaken’ cells of 28,000 Old woolly mammoth

Japanese scientists ‘reawaken’ cells of 28,000 Old woolly mammoth

Japanese scientists 'reawaken' cells of 28,000 Old woolly mammoth

Her name is Yuka: an ancient woolly mammoth that last lived some 28,000 years ago, before becoming mummified in the frozen permafrost wastelands of northern Siberia.

But now that icy tomb is no longer the end of Yuka’s story.

The mammoth’s well-preserved remains were discovered in 2010, and scientists in Japan have now reawakened traces of biological activity in this long-extinct beast – by implanting Yuka’s cell nuclei into the egg cells of mice.

“This suggests that, despite the years that have passed, cell activity can still happen and parts of it can be recreated,” genetic engineer Kei Miyamoto from Kindai University told AFP.

In their experiment, the researchers extracted bone marrow and muscle tissue from Yuka’s remains, and inserted the least-damaged nucleus-like structures they could recover into living mouse oocytes (germ cells) in the lab.

Red and green dyed proteins around a mammoth cell nucleus (upper right) in a mouse oocyte (Kindai University)

In total, 88 of these nuclei structures were collected from 273.5 milligrams of mammoth tissue, and once some of these nuclei were injected into egg cells, a number of the modified cells demonstrated signs of cellular activity that precede cell division.

“In the reconstructed oocytes, the mammoth nuclei showed the spindle assembly, histone incorporation, and partial nuclear formation,” the authors explain in the new paper.

“However, the full activation of nuclei for cleavage was not confirmed.”

Despite the faintness of this limited biological activity, the fact anything could be observed at all is remarkable and suggests that “cell nuclei are, at least partially, sustained even in over a 28,000-year period”, the researchers say.

Calling the accomplishment a “significant step toward bringing mammoths back from the dead”, Miyamoto acknowledges there is nonetheless a long way to go before the world can expect to see a Jurassic Park-style resurrection of this long-vanished species.

“Once we obtain cell nuclei that are kept in better condition, we can expect to advance the research to the stage of cell division,” Miyamoto told The Asahi Shimbun.

Less-damaged samples, the researchers suggest, could hypothetically enable the possibility of inducing further nuclear functions, such as DNA replication and transcription.

Another thing needed is better technology. Previous similar work in 2009 by members of the same research team didn’t get this far – which the scientists at least partially put down to “technological limitations at that time”, and the state of the frozen mammoth tissues used.

To that end, the researchers think their new research could provide a new “platform to evaluate the biological activities of nuclei in extinct animal species” – an incremental progression to perhaps one day, maybe, seeing Yuka’s kind roam again.

The findings are reported in Scientific Reports.

MEXICO, NORTH AMERICA, WORLD

Traces of Possible Zapotec Temple Detected in Southern Mexico

Traces of Possible Zapotec Temple Detected in Southern Mexico

The Catholic Church of San Pablo in Mitla is built on the footprint of an earlier Zapotec temple.

A hidden “entrance to the underworld” built by the ancient Zapotec culture has been discovered beneath a Catholic church in southern Mexico, according to a team of researchers using cutting-edge ground-scanning technology.

The complex system of underground chambers and tunnels was built more than a millennium ago by the Zapotec, whose state arose near modern-day Oaxaca in the late sixth century B.C. and grew in grandeur as people created monumental buildings and erected massive tombs filled with lavish grave goods. 

The architectural complex at Mitla, 27 miles (44 kilometers) southeast of Oaxaca, boasts unique and intricate mosaics, having functioned as the main Zapotec religious center until the late 15th century, when the Aztec conquest likely resulted in the abandonment of the site.

The Spanish then reused stone blocks from the ruins to build the San Pablo Apostol church a century later. 

Traces of Possible Zapotec Temple Detected in Southern Mexico
Researchers use a georadar to scan the plaza in front of the Palace of the Columns.

Oral histories have long suggested that the main altar of the church was purposefully built over a sealed entrance to a vast underground labyrinth of pillars and passages that originally belonged to a Zapotec temple known as Lyobaa, which means “the place of rest.” 

Investigating this claim with modern geophysical methods, the Project Lyobaa research team announced on May 12 that they had found a complex system of caves and passageways beneath the church.

The project is a collaboration of 15 archaeologists, geophysical scientists, engineers, and conservation experts with the Mexican National Institute of Anthropology and History (INAH), the National Autonomous University of Mexico, and the ARX Project.

A seismic tomography scan shows areas of low velocity (blue) that may indicate underground chambers or natural cavities.

Using three nondestructive methods — ground penetrating radar, electrical resistivity tomography and seismic noise tomography — the team produced a virtual 3D model of the subterranean ruins.

These methods work by measuring reflection properties of electromagnetic and seismic waves as they pass through different subsoil layers and other material underground.

A number of measuring devices placed around the church recorded information about a large void below the main altar and two connecting passages, all at a depth of 16 to 26 feet (5 to 8 meters). 

“The newly discovered chambers and tunnels directly relate to the ancient Zapotec beliefs and concepts of the Underworld,” Marco Vigato, founder of the ARX Project, told Live Science in an email, “and confirm the veracity of the colonial accounts that speak of the elaborate rituals and ceremonies conducted at Mitla in subterranean chambers associated with the cult of the dead and the ancestors.” 

A ground-penetrating radar scan shows a stairway under the surface.

Although the team suspected that the underground temple existed, they were surprised by its scale and depth, according to Vigato. “More research is needed to accurately determine the full extent of these subterranean features,” he said.

José Luis Punzo Díaz, an archaeologist at Centro INAH Michoacán who was not involved in the research, told Live Science in an email that “geophysical methods are very important in current archaeology.”

These methods have helped find anomalies at other Mesoamerican sites, such as Teotihuacán, which have also been interpreted as entrances to the underworld.

As a result, these methods “should be contrasted with archaeological excavations,” Punzo noted, “because although the geophysical data are interesting, it is always essential to verify them in the field.” 

The joint research team has plans for a second season of geophysical investigation in September, which will focus on additional groups of structures at Mitla, and they hope to get permission from authorities to conduct further work at San Pablo Apostol as well, Vigato said.

All told, “these findings will help rewrite the history of the origins of Mitla and its development as an ancient site,” the team members wrote in a statement.

AFRICA, EGYPT, WORLD

Paint like an Egyptian: X-rays reveal creative process behind ancient tomb art

Paint like an Egyptian: X-rays reveal creative process behind ancient tomb art

Every painter has a process, but the painstaking revisions and countless tiny edits are invisible to those who only see the final product. In a study published today in PLOS ONE, researchers used x-rays to reveal how 3000-year-old paintings inside Egypt’s Theban Necropolis unfolded step by step.

Paint like an Egyptian: X-rays reveal creative process behind ancient tomb art
Inside the Theban Necropolis, researchers used an x-ray fluorescence machine to peek behind the surface layers of ancient paintings lining tomb walls

The findings hint at the creative process used to produce these ancient masterworks.

Applying the x-ray method to ancient Egyptian wall paintings “is really a game changer,” says Marine Cotte, a chemist at the European Synchrotron Radiation Facility, who previously collaborated with the study’s authors but was not involved with this work.

In recent years, scientists and art historians around the world have teamed up to use a technology known as x-ray fluorescence to identify paint colors and traced lines buried beneath the surface of famous works of art.

Every paint color has a distinct chemical composition. By bombarding paintings with x-rays and measuring how they are absorbed, scientists can fingerprint the pigments both at the surface and below.

The technique allows scientists to see the mistakes artists covered up, as well as the layer-by-layer iterations that resulted in famous end results.

Most of this work has happened in museums or laboratories, where smaller, portable objects can be brought to the machine. That’s tough to do with paintings on the wall of an underground tomb. So, using two portable x-ray machines, an interdisciplinary team of art historians, Egyptologists, and engineers brought the lab to the tombs instead, allowing the researchers to look beneath the surface without destroying it.

The Theban Necropolis—which includes Tutankhamun’s tomb—features hundreds of tombs, each chock full of paintings memorializing the dead.

Many art historians consider them to represent the peak of ancient Egyptian painting. X-raying them wasn’t easy: Getting the devices into the tombs meant carrying the sensitive machines through the desert into hard-to-reach areas off-limits to tourists.

Once inside the warm, humid funerary chapels, the work was slow and painstaking.

A small area could take 3 hours to scan, as crouching scientists worked centimeter by centimeter in total silence. “You feel in the heart of humanity,” says study co-author Catherine Defeyt, an art conservation scientist at the University of Liège, of working in the tombs.

When the researchers emerged to analyze their data, the results surprised them.

Many Egyptologists believed the sheer number of Egyptian paintings inside the Necropolis would have required an assembly line process, with no room for artists to return and redo work.

Yet x-rays of a well-known portrait of Rameses II, who ruled Egypt from 1279 B.C.E. to 1213 B.C.E., revealed traces of an earlier version underneath.

The previous depiction of Rameses II had a shorter crown, a different scepter, and an altered necklace—“a remarkable encounter with the ghost of the painters at work,” the team writes in the paper.

Thomas Christiansen—an Egyptologist with the Danish National Encyclopedia who wasn’t involved with the research—says the amount of reworking surprised him.

The hidden details, he says, help us “understand and appreciate the ancient Egyptian artist.” But just why the painters revised their work, changing small details like an arm’s position, may be “impossible to fathom” today, the authors note.

Christiansen speculates that the revisions suggest a master artist envisioned the project, whereas apprentices applied the paint, and the master later issued corrections. “More effort went into realizing a preconceived artistic idea than we thought,” he says.

The fact that they altered paintings at all challenges many historians’ assumptions about Egyptian art as preplanned and precise, says Philippe Martinez, lead author on the study and an Egyptologist at Sorbonne University. “What we see is that nothing is perfect. And that’s great, because they were human beings.”

EUROPE, IRELAND, WORLD

Dublin hotel dig unearths 1,000-year-old burial site

Dublin hotel dig unearths 1,000-year-old burial site

Dublin hotel dig unearths 1,000-year-old burial site
A member of the archaeology team examines skeletal remains discovered during preparatory works for a new hotel in central Dublin

About 100 skeletal remains from the Middle Ages have been unearthed during excavations for a Northern Ireland firm’s new hotel in Dublin.  Burial sites dating back more than 1,000 years were found at Capel Street where an abbey, St Mary’s, once stood.

At least two of the remains are believed to date back to the early 11th Century. The excavations have been commissioned by Beannchor, which is building its new Bullitt Dublin hotel on the site.

The abbey used by the Savigniac and Cistercian orders opened in the 12th Century. Carbon dating of one of the discovered graves predates that by 100 years, indicating the presence of a Christian settlement on the site prior to St Mary’s being built.

The archaeological investigations at the site, which formerly housed Boland’s Bakery, also unearthed the foundations of buildings dating back to the 1600s.

Edmond O’Donovan, director of excavations for Courtney Deery Heritage Consultancy (CDHC), at the Capel Street site

The finds were discovered close to a former Presbyterian meeting house dating from 1667. Parts of a domestic house known as the ‘Dutch Billies’ have also been found.

It was constructed in about 1700 by settlers who came to Dublin after William of Orange ascended to the thrones of England, Scotland and Ireland in 1689.

Incorporated into design

While the skeletal remains will be painstakingly excavated, cleaned and sent for further analysis, before ultimately being given to the National Monuments Services, the other structures found during the examination of the site are set to be incorporated into the design of the new hotel complex.

Beannchor Group, which runs high-profile hotels and bars in Northern Ireland, has undertaken similar restoration of historic buildings in the past, including Belfast’s Merchant Hotel, which was a former bank.

It said the Dublin project is by far its biggest and most complex project to date.

The 17th Century Presbyterian meeting house will be central to the development of a new bar and restaurant concept.

The ‘Dutch Billies’ house will also be preserved while a building with surviving ovens from the Boland’s Bakery dating from 1890 will be renovated and repurposed.

Edmond O’Donovan, director of excavations for Courtney Deery Heritage Consultancy (CDHC, said St Mary’s Abbey was Ireland’s largest and most wealthy medieval abbey in its day.

Archaeologists examine remains at the site of the medieval St Mary’s Abbey

“It was demolished after 1540 when the monastery was disbanded by Henry VIII and was later the site of a 17th Century Presbyterian meeting house.

“One of the things that was intriguing and exciting about the excavation is that we found an early burial or at least a number of burials that we suspect to be quite early.

“We have one that’s carbon dated to the 11th Century and we have a second burial that was found with a diagnostic stick pin from the 11th Century.

“And that suggests that there was an earlier Christian and potentially monastic foundation here which predates the Savigniac and Cistercian Abbey.”

Bill Wolsey, managing director of Beannchor, said it was impossible to have foreseen what the project would entail at its outset in 2017.

“As time went on, we began to understand just how complex this project may be,” he said.

Skeletal remains unearthed at the site of a new hotel being developed by Belfast-based Beannchor Group in Dublin

“Great care has been taken to preserve and incorporate elements of these early surviving buildings into the new development, on what we now know is one of the most significant heritage sites in the city.”

The new Bullitt Dublin hotel is expected to open in 2025.

AFRICA, EGYPT, WORLD

Archaeologists Find Massive 3,000-Year-Old Statue in Cairo Slum

Archaeologists Find Massive 3,000-Year-Old Statue in Cairo Slum

A woman walks past the head of a statue at the site of the new discovery in Cairo’s Mattarya district on Thursday.

Archaeologists have found a 26-foot statue submerged in ground water in a Cairo slum that the Antiquities Ministry has hailed as one of the most important discoveries ever.

Experts say it probably depicts the revered Pharaoh Ramses II, who ruled Egypt more than 3,000 years ago.

The was unearthed near the ruins of Ramses II’s temple in the ancient city of Heliopolis, which is located in the eastern part of modern-day Cairo.

“Last Tuesday they called me to announce the big discovery of a colossus of a king, most probably Ramses II, made out of quartzite,” Antiquities Minister Khaled al-Anani said Thursday.

The quartzite colossus possibly of Ramses II and the limestone bust of Seti II were unveiled on Thursday.

The most powerful and celebrated ruler of ancient Egypt, the pharaoh also known as Ramses the Great was the third of the Nineteenth Dynasty of Egypt.

He led several military expeditions and expanded the Egyptian Empire to stretch from Syria in the east to Nubia in the south. His successors called him the “Great Ancestor.”

On Thursday, archaeologists, officials, local residents, and members of the news media looked on as a massive forklift pulled the statue’s head out of the water

The joint Egyptian-German expedition also found the upper part of a life-sized limestone statue of Pharaoh Seti II, Ramses II’s grandson, that is 31 inches long.

The torso of the statue of Pharaoh Ramses II was unveiled on Thursday.

The sun temple in Heliopolis was founded by Ramses II, lending weight to the likelihood the statue is of him, archaeologists say.

It was one of the largest temples in Egypt, almost double the size of Luxor’s Karnak, but was destroyed in Greco-Roman times.

Many of its obelisks were moved to Alexandria or to Europe and stones from the site were looted and used for building as Cairo developed.

“It is one of the most important excavations in Egypt,” Dr. Salima Ikram, an archaeologist and professor of Egyptology at the American University in Cairo who was part of the dig this week told NBC News. She described the new find as “spectacular, the things are astonishing.”

She said the ongoing work at the site is “crucially important because it is basically rescue archaeology of one of the most important religious places in ancient Egyptian history. It is the birthplace of the Sun God and indeed of Egypt and its civilization in terms of Egyptian mythology.”

Experts will now attempt to extract the remaining pieces of both statues before restoring them. If they are successful and the colossus is proven to depict Ramses II, it will be moved to the entrance of the Grand Egyptian Museum, set to open in 2018.

The discovery was made in the working-class area of Matariya, among unfinished buildings and mud roads.

Egyptian Antiquities Minister Khaled el-Anani poses for a picture with workers next to the head of a statue on Thursday.
EUROPE, IRELAND, WORLD

The Newgrange of Ireland is older than the Egyptian pyramids and Stonehenge

The Newgrange of Ireland is older than the Egyptian pyramids and Stonehenge

The Newgrange of Ireland is older than the Egyptian pyramids and Stonehenge
The Newgrange tomb in County Meath, Ireland, just north of Dublin.

Newgrange is a 5,200-year-old ancient tomb located in the Boyne Valley in Ireland’s Ancient East. Archaeologists have classified Newgrange as a passage tomb, but Newgrange is now considered to be much more than a passage tomb.

Newgrange was built about 5,200 years ago (3,200 BC). While the name is not as unheard of as they are, that makes it older than Stonehenge and the Great Pyramids of Giza.

The mound is 85m (279ft) in diameter and 13m (43ft) high, an area of about 1 acre. A passage measuring 19m (62ft) leads into a chamber with 3 alcoves. The passage and chamber are aligned with the rising sun on the mornings around the Winter Solstice.

Newgrange is surrounded by 97 large stones called kerbstones some of which are engraved with megalithic art; the most striking is the entrance stone.

Newgrange was founded by a farming community that thrived in the Boyne Valley’s fertile soils. Knowth and Dowth are two comparable mounds that, along with Newgrange, have been listed as UNESCO World Heritage Sites.

The engraved stone at the entrance to Newgrange.
William Frederick Wakeman’s map of the burial chambers inside the tomb

An ancient temple is a more appropriate description, a location of astrological, spiritual, religious, and ceremonial importance, similar to how modern cathedrals are sites of prestige and reverence where dignitaries might be put to rest.

Newgrange is a massive kidney-shaped mound that spans over an acre and is held together at the base by 97 kerbstones, some of which are highly adorned with megalithic art.

The inner corridor is 19m long and leads to a cruciform room with a corbelled ceiling. The amount of time and labor put into Newgrange’s development shows a well-organized society with specialized organizations in charge of various parts of the building.

Newgrange is part of the Brú na Bóinne group of monuments erected around a bend of the Boyne River. Knowth (the biggest) and Dowth are the other two major monuments, though there are up to 35 lesser mounds scattered around the region.

Newgrange is best known for the illumination of its passage and chamber by the winter solstice sun.
A young girl stands in front of the entrance to Newgrange in about 1905

Winter Solstice

Newgrange is well renowned for the winter solstice sun’s lighting of its corridor and chamber.

A roof-box is an aperture above the entrance to the route at Newgrange. This baffling orifice held a great surprise for those who unearthed it. Its aim is to allow sunlight into the chamber on the shortest days of the year, which occur around December 21st, the winter solstice.

As the sun rises higher in the sky, the beam within the chamber expands, illuminating the entire space significantly. This event lasts 17 minutes and starts at about 9 a.m. When one considers that Newgrange was created 500 years before the Great Pyramids and almost 1,000 years before Stonehenge, its precision as a time-telling device is amazing.

The intent of the Stone Age farmers who build Newgrange was undoubtedly to mark the beginning of the new year. In addition, it may have served as a powerful symbol of the victory of life over death.

Every year, the winter solstice celebration in Newgrange draws a lot of attention.

Many people assemble at the old tomb to await daybreak, just as they did 5,000 years ago.  So great is the demand to be one of the few inside the chamber during the solstice that there is a free annual lottery (application forms are available at the Visitor Centre)

EUROPE, NORWAY, WORLD

Viking sword from warrior’s grave unearthed in family’s yard in Norway

Viking sword from warrior’s grave unearthed in family’s yard in Norway

Viking sword from warrior's grave unearthed in family's yard in Norway
The sword was found in a yard belonging to Anne and Oddbjørn Holum Heiland, where they were clearing land to build an extension to their house.

A man digging in his yard to build an extension of his house in southern Norway has unearthed the 1,100-year-old grave of a Viking warrior who was buried with weapons.

The finds include a rusty iron sword in two pieces; its hilt style enabled archaeologists to date the burial to the late 800s or early 900s, during the Viking Age, Joakim Wintervoll — an archaeologist who works for the local government of Agder County, where the relics were found — told Live Science.

“We have a good record of how the ‘fashion’ in the shapes of sword handles developed in Norway, from early ages up to more modern eras,” he said. “Comparing it to other known sword handles, we believe this sword is from the late ninth century to the 10th century.” 

The sword and other artifacts are from a Viking Age grave. A similar Viking grave was found in the 1930s at a farm nearby.

Other artifacts found in the grave included a long spear designed to be used on horseback, called a lance; glass beads and a belt buckle gilded with gold; and a bronze brooch. Neither human nor animal remains have yet been discovered there.

The artifacts seem to have belonged to a Viking warrior. “The lance suggests that this was someone that was proficient in combat from horseback,” Wintervoll said. And the warrior was “definitely someone of means, based on the gold-gilded jewelry.”

The grave can be dated from the style of the sword’s hilt, which indicates it was made at the turn of the ninth and 10th centuries.
The blade of a lance — a long spear designed to be used from horseback — was also found in the grave, but no human or animal remains were found.

Viking burial

The grave and its artifacts were discovered in late June in the yard of a house in the mainly rural district of Setesdal, beside a lake about 125 miles (200 kilometers) southwest of Oslo. Homeowner Oddbjørn Holum Heiland had started using a mechanical digger to clear the spot in his yard where he and his wife Anne planned to extend their house, according to Science Norway.

“I wasn’t going to dig a lot, just a little bit in the slope behind the house, to get some more space between the house and the land,” he told the news outlet.

Although rare, the Viking sword is not unique. Viking graves often contained a warrior’s weapons, and more than 3,000 have been found in Norway.
Other artifacts from the Viking grave include a bronze brooch, part of a metal belt buckle and glass beads gilded with gold.

He first found an oblong slab just below the surface; it’s now been recognized as a gravestone. Further digging revealed the hilt of the sword; Holum Heiland then realized his yard must hold other Viking artifacts, so he stopped digging and called the county archaeologists.

Wintervoll and Jo-Simon Frøshaug Stokke, an archaeologist from Oslo’s Museum of Cultural History, visited the site a few days later. No Viking artifacts had been found before at the property, Wintervoll said, but a Viking grave containing a sword, spear, glass beads and a horse bridle were discovered on a nearby farm in the 1930s.

Although it’s “a bit too early to say” whether these two graves have a connection, “it is interesting that they are relatively close and have almost identical finds in them,” he said.

Ancient claim 

It is possible that a Viking warrior was buried at the site as a way for their descendants to claim ownership of the land around it, Wintervoll said. Or, perhaps it had only family significance.

“No grave mound was known to have been on this homestead,” Wintervoll said. In Norway, this type of grave is known as a “flatmarksgrav,” which translates to “flat field grave,” he added.

The person interred there might have been buried whole, or cremated ashes may have been laid down in the grave. “At this point in time, the practice varied a bit from place to place, but we have yet to find any burnt bones,” he said. 

The grave seems to have been dug on an almost east-west axis, which would align with sunrise and sunset, and the only grave marker seems to have been the oblong stone above it.

“Right now, we don’t think this is a grave that was meant to be visible at a great distance,” Wintervoll said. “These types of graves might have a more family or private function.” 

ASIA, CHINA, WORLD

Tiny, 540-Million-Year-Old Human Ancestor Didn’t Have an Anus

Tiny, 540-Million-Year-Old Human Ancestor Didn’t Have an Anus

The Oldest Signs of Modern Humans From 86,000 Years Ago Found in Laotian Cave
A scanning election microscope (SEM) took this detailed image of the deuterostome with the extra-large mouth. 

A speck-size creature without an anus is the oldest known prehistoric ancestor of humans, a new study finds. Researchers found the remains of the 540-million-year-old critter — a bag-like sea organism — in central China.

The creature is so novel, it has its own family (Saccorhytidae), as well as its own genus and species (Saccorhytus coronaries), named for its wrinkled, sac-like body. (“Saccus” means “sac” in Latin, and “rhytis” means “wrinkle” in Greek.)

S. coronaries, with its oval body and large mouth, is likely a deuterostome, a group that includes all vertebrates, including humans, and some invertebrates, such as starfish.

“We think that as an early deuterostome, this may represent the primitive beginnings of a very diverse range of species, including ourselves,” Simon Conway Morris, a professor of evolutionary palaeobiology at the University of Cambridge, said in a statement. “To the naked eye, the fossils we studied look like tiny black grains, but under the microscope the level of detail is jaw-dropping.”

At first glance, however, S. coronaries do not appear to have much in common with modern humans. It was about a millimeter (0.04 inches) long, and likely lived between grains of sand on the seafloor during the early Cambrian period.

While the mouth onS. coronaries were large for its teensy body, the creature doesn’t appear to have an anus.

“If that was the case, then any waste material would simply have been taken out back through the mouth, which from our perspective sounds rather unappealing,” Conway Morris said.

Tiny ancestor

Other deuterostome groups are known from about 510 million to 520 million years ago, a time when they had already started to evolve into vertebrates, as well as sea squirts, echinoderms (starfish and sea urchins), and hemichordates (a group that includes acorn worms).

However, these incredibly diverse animals made it hard for scientists to figure out what the common deuterostome ancestor would have looked like, the researchers said.

The newfound microfossils answered that question, they said. The researchers used an electron microscope and a computed tomography (CT) scan to construct an image of S. coronaries.

“We had to process enormous volumes of limestone — about 3 tonnes [3 tons] — to get to the fossils, but a steady stream of new finds allowed us to tackle some key questions: Was this a very early echinoderm or something even more primitive?” study co-researcher Jian Han, a paleontologist at Northwest University in China, said in the statement. “The latter now seems to be the correct answer.”

The analysis indicated that S. coronaries had a bilaterally symmetrical body, a characteristic it passed down to its descendants, including humans. It was also covered with thin, flexible skin, suggesting it had muscles of some kind that could perhaps help it wriggle around in the water and engulf food with its large mouth, the researchers said.

Small, conical structures encircling its mouth may have allowed the water it swallowed to escape from its body. Perhaps these structures were the precursor of gill slits, the researchers said.

An artist’s interpretation of Saccorhytus coronaries, which measured about a millimeter in size.

Molecular clock

Now that researchers know that deuterostomes existed 540 million years ago, they can try to match the timing to estimates from biomolecular data, known as the “molecular clock.”

Theoretically, researchers can determine when two species diverged by quantifying the genetic differences between them. If two groups are distantly related, for instance, they should have extremely different genomes, the researchers said.

However, there are few fossils from S. coronaries’ time, making it difficult to match the molecular clocks of other animals to this one, the researchers said. This may be because animals before deuterostomes were simply too minuscule to leave fossils behind, they said.

The findings were published online in the journal Nature.

In another paper, researchers reported on the discovery of another type of tiny animal fossil from the late Cambrian. These creatures, called loriciferans, measured about 0.01 inches (0.3 mm) and, like S. coronaries, lived between grains of sand, the researchers said in a study published online today in the journal Nature Ecology and Evolution.

The newly identified species, Eolorica deadwoodensis, discovered in western Canada, shows when multicellular animals began living in areas once inhabited by single-celled organisms, the researchers said.