School lesson gone wrong leads to new, bigger megalodon size estimate

FLORIDA MUSEUM OF NATURAL HISTORY

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IMAGE: SCIENTISTS HAVE BEEN TRYING TO ESTIMATE THE SIZE OF OTODUS MEGALODON FOR MORE THAN A CENTURY, USING THE MANY FOSSIL TEETH THE GIANT SHARK LEFT BEHIND. A NEW, MORE RELIABLE... view more 

CREDIT: KRISTEN GRACE/FLORIDA MUSEUM OF NATURAL HISTORY

GAINESVILLE, Fla. --- A more reliable way of estimating the size of megalodon shows the extinct shark may have been bigger than previously thought, measuring up to 65 feet, nearly the length of two school buses. Earlier studies had ball-parked the massive predator at about 50 to 60 feet long.

The revised estimate is the result of new equations based on the width of megalodon's teeth - and began with a high school lesson that went awry.

Victor Perez, then a doctoral student at the Florida Museum of Natural History, was guiding students through a math exercise that used 3D-printed replicas of fossil teeth from a real megalodon and a set of commonly used equations based on tooth height to estimate the shark's size. But something was off: Students' calculations ranged from about 40 to 148 feet for the same shark. Perez snapped into trouble-shooting mode.

"I was going around, checking, like, did you use the wrong equation? Did you forget to convert your units?" said Perez, the study's lead author and now the assistant curator of paleontology at the Calvert Marine Museum in Maryland. "But it very quickly became clear that it was not the students that had made the error. It was simply that the equations were not as accurate as we had predicted."

Although the equations have been widely used by scientists since their publication in 2002, the classroom exercise revealed they generate varying size estimates for a single shark, depending on which tooth is measured.

"I was really surprised," Perez said. "I think a lot of people had seen that study and blindly accepted the equations."

For more than a century, scientists have attempted to calculate the size of megalodon, whose name means "big tooth." But the only known remains of the fearsome shark that dominated oceans from about 23 to 3.6 million years ago are fossilized teeth and a few, rare vertebrae. Like other sharks, the rest of megalodon's skeleton, including its jaw, was composed of lightweight cartilage that decomposed quickly after death. Tooth enamel, however, "preserves really well," Perez said. "It's probably the most structurally stable thing in living organisms." Megalodon sharks shed thousands of teeth over a lifetime, leaving abundant traces of the species in the fossil record.

The most accepted methods for estimating the length of megalodon have used great white sharks as a modern proxy, relying on the relationship between tooth size to total body length. While great white sharks and megalodon belong to different families, they share similar predatory lifestyles and broad, triangular teeth serrated like steak knives - ideal adaptations for hunting large, fleshy marine mammals such as whales and dolphins, Perez said.

But these methods also present a challenge: To generate body length estimates, they require the researcher to correctly identify a fossil tooth's former position in a megalodon jaw. As in humans, the size and shape of shark teeth vary depending on where they're located in the mouth, and megalodon teeth are most often found as standalone fossils.

So, Perez was ecstatic when fossil collector Gordon Hubbell donated a nearly complete set of teeth from the same megalodon shark to the Florida Museum in 2015, reducing the guesswork. After museum researchers CT scanned the teeth and made them available online, Perez collaborated with teacher Megan Higbee Hendrickson on a plan to incorporate them into her middle school curriculum at the Academy of the Holy Names school in Tampa.

"We decided to have the kids 3D-print the teeth, determine the size of the shark and build a replica of its jaw for our art show," Hendrickson said.

Perez and Hendrickson co-designed a lesson for students based on the then-most popular method for estimating shark size: Match the tooth to its position in the shark jaw, look up the corresponding equation, measure the tooth from the tip of the crown to the line where root and crown meet and plug the number into the equation.

After a successful pilot test of a few teeth with Hendrickson's students, he expanded the lesson plan to include the whole set of megalodon teeth for high school students at Delta Charter High School in Aptos, California. Perez expected a slight variability of a couple millimeters in their results, but this time, variations in students' estimates shot to more than 100 feet. The farther a tooth position was from the front of the jaw, the larger the size estimate.

After Perez detailed the lesson's results in a fossil community newsletter, he received an email from Teddy Badaut, an avocational paleontologist in France. Badaut suggested a different approach. Why not measure tooth width instead of height? Previous research had suggested tooth width was limited by the size of a shark's jaw, which would be proportional to its body length.

Ronny Maik Leder, then a postdoctoral researcher at the Florida Museum, worked with Perez to develop a new set of equations based on tooth width.

By measuring the set of teeth from Hubbell, "we could actually sum up the width of the teeth and get an even better approximation of the jaw width," Perez said.

The researchers analyzed sets of fossil teeth from 11 individual sharks, representing five species, including megalodon, its close relatives and modern great white sharks.

By measuring the combined width of each tooth in a row, they developed a model for how wide an individual tooth was in relation to the jaw for a given species. Now when a paleontologist unearths a lone megalodon tooth the size of their hand, they can compare its width to the average obtained in the study and get an accurate estimate of how big the shark was.

"I was quite surprised that indeed no one had thought of this before," said Leder, now director of the Natural History Museum in Leipzig, Germany. "The simple beauty of this method must have been too obvious to be seen. Our model was much more stable than previous approaches. This collaboration was a wonderful example of why working with amateur and hobby paleontologists is so important."

Perez cautioned that because individual sharks vary in size, the team's methods still have a range of error of about 10 feet when applied to the largest individuals. It's also unclear exactly how wide megalodon's jaw was and difficult to guess based on teeth alone - some shark species have gaps between each tooth while the teeth in other species overlap.

"Even though this potentially advances our understanding, we haven't really settled the question of how big megalodon was. There's still more that could be done, but that would probably require finding a complete skeleton at this point," he said.

Perez continues to teach the megalodon tooth lesson, but its focus has changed.

"Since then, we've used the lesson to talk about the nature of science - the fact that we don't know everything. There are still unanswered questions," he said.

For Hendrickson, the lesson sparked her students' enthusiasm for science in ways that textbooks could not.

"Victor was an amazing role model for the kids. He is the personification of a young scientist that followed his childhood interest and made a career out of it. So many of these kids had never worked with or spoken to a scientist who respected their point of view and was willing to answer their questions."

Leder and Badaut co-authored the study.

CAPTION

Like other sharks, megalodon's skeleton was made of cartilage, which quickly decomposes after death. Researchers rely on its fossil teeth to estimate its size, using the great white shark as a proxy. While the two species belong to different families, they share similar lifestyles and tooth structure.

CREDIT

Kristen Grace/Florida Museum of Natural History

 

Ancient chickens lived significantly longer than modern fowl because they were seen as sacred, not food -- study shows

UNIVERSITY OF EXETER

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IMAGE: IRON AGE COCKEREL FROM HOUGHTON DOWN, HAMPSHIRE, RADIOCARBON DATED TO THE 4TH-3RD CENTURY BC. ANALYSIS OF THE SPURS SUGGESTS THE BIRD LIVED TO AT LEAST TWO YEARS OLD. view more 

CREDIT: JULIA BEST

Ancient chickens lived significantly longer than their modern equivalents because they were seen as sacred - not food - archaeologists have found.

Experts have developed the first reliable method of finding the age of fowl who lived thousands of years ago. Their research shows they lived to advanced ages, and were kept for ritual sacrifice or cockfighting rather than meat or egg production.

Chickens today live for a few weeks (in the UK poultry birds live for between 33 and 81 days), but during the Iron Age, Roman and Saxon period they lived up to the age of two, three or even four years old.

Calculating the age of bird remains is hard because techniques used for mammals, such as bone fusion and tooth wear, are not available. Researchers have devised a new method based on size of the tarsometatarsal spur which develops on the leg of adult cockerels.

The new method was tested on modern birds of known-age and then applied to ancient specimens. This has allowed the experts to reconstruct the demographics of domestic fowl from Iron Age to Early Modern sites in Britain to reveal changes in relationships between humans and fowl.

Of the 123 Iron Age, Roman and Saxon bones analysed, over 50 per cent were of chickens aged over two years, and around 25 per cent over three years.

Dr Sean Doherty, from the University of Exeter, who led the study, said: "Domestic fowl were introduced in the Iron Age and likely held a special status, where they were viewed as sacred rather than as food. Most chicken bones show no evidence for butchery, and were buried as complete skeletons rather than with other food waste"

"The study confirms the special status of these rare and highly prized birds, showing that from the Iron Age to Saxon period they were surviving well past sexual maturity. Most lived beyond a year, with many reaching the age of two, three and four years old. The age of which cockerels then started to die at becomes younger after this period."

Experts carried out analysis on modern leg bones from domestic fowl and red jungle fowl of known age and sex from multiple collections. This revealed that the bony spur only develops in older birds.

Of the 69 cockerels aged below 1 year, only 14 (20 per cent) had developed a spur. The only age in which all cockerels had a spur was those aged over 6 years. Consequently, there is the potential for archaeologists to misidentify young cockerels without a spur as hens.

Once fully developed, the spur increases in size and its length in relation to the length of the leg can be used to estimate age.

The researchers also took measurements from 1,368 domestic fowl leg bones from British sites dating from the Iron Age to modern period to reconstruct the age when they had died and their sex. This suggested during the Iron Age and Roman period there were significantly more cockerels than hens, likely due to the popularity of cockfighting in this period.

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The research was carried out by Sean Doherty, Caroline Skelton, Rebecca Smallman, and Naomi Sykes from the University of Exeter; Alison Foster; Peta Sadler; Julia Best from the University of Cardiff and Bournemouth University, Sheila Hamilton Dyer from Bournemouth University; James Morris from the University of Central Lancashire; Helina Woldekiros from Washington University in St. Louis and Richard Thomas from the University of Leicester.

This study, Estimating the age of domestic fowl (Gallus gallus domesticus L. 1758) cockerels through spur development, is published in the International Journal of Osteoarchaeology. https://doi.org/10.1002/oa.2988.

 

Paleontologists for the first time discover the pierced skull of a Pleistocene cave bear

Probably the find is the only evidence in the world that ancient people hunted Pleistocene small cave bears

URAL FEDERAL UNIVERSITY

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IMAGE: SUCH ARROWHEAD (LEFT) WAS PROBABLY USED TO KILL THE BEAR. view more 

CREDIT: URFU / ELIZAVETA VERETENNIKOVA.

Russian paleontologists discovered the skull of a Pleistocene small cave bear with artificial damage in the Imanay Cave (Bashkiria, Russia). A bear aged 9-10 years was killed with a spear during hibernation about 35 thousand years ago. If the assumptions of scientists are confirmed, the find will become the world's first direct evidence of a Paleolithic man hunting for a small cave bear. The description of the skull was published in the Vestnik Archeologii, Anthropologii I Ethnographii.

"The hole in the skull could be either natural or artificial," said senior researcher of the laboratories at the Ural Branch of the Russian Academy of Sciences and the Ural Federal University Dmitry Gimranov. "In the first case, for example, a stone could fall on the bear's head, or water dripped onto the skull during thousands of years. But this is highly unlikely. Most likely the animal was killed by ancient people."

To establish whether the bear was killed or not, scientists have to find out when the hole was made - during life or after the death of the animal. In the second case, the hole can be evidence of a ritual.

"In the Paleolithic, ritual, sacred practices were widespread," said Dmitry Gimranov. "These are handicrafts made of bones, and drawings on the walls of caves not only mammoths' and much more. Therefore, a hole in the skull could have been made after the death of the bear as a ritual practice. The facts of hunting for bears in general at that time are extremely rare. For example, in Europe, many cave bears' bones of were found. But for millions of finds, only 20-30 bones have traces of felling, which means that the meat was removed from the animal for eating. And there is only one fact of the hunt. European researchers have found a stone tip in the vertebra of a bear. There have been no such finds in Russia before. Moreover, all found with traces of human hands belong to large cave bears."

As Gimranov said, hunting for large mammals was essential for life support of ancient humans. However, hunting for small cave bears was not a specialty of the ancient hunters who left traces of their stay in the Imanay cave. At the same time, Paleo human has such strength that he could pierce the bear skull with a spear at close range with relative ease.

Note

The excavations in the Imanay cave, which is located in the Bashkiria National Park, have been carried out by researchers for three years. During this time, paleontologists have collected more than 10 thousand remains of the Late Pleistocene period. Researchers from Yekaterinburg, Moscow, Ufa take part in this study.

Cave bears inhabited the territory of northern Eurasia in the Late Pleistocene (250-10 thousand years ago). These animals were often found in the faunas of Western Europe, the Russian Caucasus, and the Urals. Finds of cave bear bones are common in caves and sometimes form huge clusters. But the caves were inhabited not only by animals but also by ancient man. Therefore, the joint finding of the bones of a cave bear and artifacts is not uncommon. However, the Pleistocene small cave bear is not a very common type of cave bear. For the first time, its remains were found in Great Britain in 1922. Later, the Russian academician Aleksey Borisyak collected and described more voluminous material in Krasnodar (Russia). He named the new species the Russian cave bear. Subsequently, it became known as the "small cave bear". Both in Russia and the West, "traces" of this species are very rare.

Really large finds are associated with excavations in the 1970s - 1980s in the Kizel Cave in the Perm Region (the finds are stored in St. Petersburg). Ural paleontologists were fortunate enough to discover the Imanay cave, where the bones of a small cave bear turned out to be several times larger than in Kizel Cave. Today, Imanay Cave is the largest deposit of the remains of a small cave bear in the world.

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Fragility fractures cost European health care systems €56.9 billion annually

New International Osteoporosis Foundation report provides unique overview of osteoporosis in Europe, revealing the enormous disease burden and an unacceptable treatment gap; 71% of women at high risk of fracture are not receiving much-needed medication

INTERNATIONAL OSTEOPOROSIS FOUNDATION

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IMAGE: SCOPE 2021 SCORECARD FOR OSTEOPOROSIS IN EUROPE ILLUSTRATES THE SCORES ACROSS FOUR DOMAINS FOR 29 COUNTRIES IN EUROPE (EU27 +2). THE ELEMENTS OF EACH DOMAIN IN EACH COUNTRY WERE SCORED... view more 

CREDIT: INTERNATIONAL OSTEOPOROSIS FOUNDATION

June 7, 2021 - Nyon, Switzerland -- A new report by the International Osteoporosis Foundation (IOF) draws attention to the burden of osteoporosis and the gaps and inequalities in the provision of primary and secondary prevention of fractures due to osteoporosis across Europe. 'SCOPE 2021: a new scorecard for osteoporosis in Europe' provides detailed findings for the 27 countries of the European Union as well as Switzerland and the United Kingdom (referred to as 'EU27+2'), covering key indicators for four domains: burden of disease, policy framework, service provision and service uptake.

Professor John A. Kanis, IOF Honorary President and lead author of SCOPE, stated:

"Osteoporosis is a major concern in Europe as it results in 4.3 million fragility fractures and health care costs in excess of €56 billion annually. Seeking to prioritize osteoporosis prevention in the EU27+2 countries, the SCOPE 2021 report has tracked key indicators of burden and service uptake which will help Europeans measure how well their country is able to provide quality care, including access to risk assessment and medications. It also provides a new benchmark to follow trends in osteoporosis management, and to measure future progress."

Osteoporosis is a progressive chronic disease that causes bones to become fragile and weak, leaving individuals at high risk of fragility fractures. Such fractures can have a serious impact on the sufferer, leading to pain, long-term disability and even premature death. In the EU27+2, there were estimated to be more than a quarter of a million fragility fracture-related deaths in 2019. This number is comparable to, or exceeds, other common causes of death such as lung cancer, diabetes, or chronic lower respiratory diseases.

Osteoporosis and fragility fractures place a heavy burden on Europe's population

SCOPE 2021 examined the burden of osteoporosis and fragility fractures in the EU27+2 countries, finding:

• The total direct cost of fragility fractures was immense at €56.9 billion in 2019. This comprises €36.3 billion for direct costs of incident fractures, €19.0 billion for ongoing long-term disability costs (from fractures that occurred before 2019), and €1.6 billion for assessment and pharmacological treatment.

• The average direct cost of osteoporotic fractures was €109.1 for each individual - in comparison, in 2010 the average for the EU27 was €85 (after adjusting for inflation).

• Based on the WHO / bone mineral density criteria, there were approximately 32.0 million individuals with osteoporosis, of which 6.5 million were men and 25.5 million were women (2019).

• An estimated 4.3 million new fragility fractures occurred in 2019--equivalent to 11,705 fractures/day (or 487 per hour).

• Based on ten-year probability of a major fracture, 23.8 million Europeans had a probability of major fracture above the thresholds for high risk.

• There was a marked difference in fracture risk among the countries. The probability of future hip fracture in men and women at the age of 50 years varied from 3.8-10.9% in men and 7.0-25.1% in women.

• Given the projected increase in the aged population, the annual number of osteoporotic fractures in the EU27+2 is projected to rise by +24.8%; from 4.28 million in 2019 to 5.34 million in 2034.

Service provision lags in many countries

SCOPE 2021 also found notable inadequacies in service provision that hinder many Europeans from getting the care they need to prevent osteoporosis and fragility fractures:

• In many countries there is suboptimal availability of DXA scanners, which are used to diagnose and monitor osteoporosis. Ten countries reported having less than the estimated minimum DXA units required, and only 15 of the 29 countries provide full reimbursement.

• A wide variety of approved medications is available for the management of osteoporosis. Less than half of the countries offered full reimbursement for these medications.

• Post-Fracture Care Coordination Programs (or Fracture Liaison Services) in hospitals were lacking in eight countries. Based on expert opinion, approximately half of the remaining countries reported that less than 10% of hospitals had such vital programs in place.

Large treatment gap indicates need for strategies to improve service uptake

Among the most startling findings of SCOPE 2021 is the enormous 'treatment gap' which is leaving the most high risk individuals unprotected against fragility fractures. Other measures of service uptake were also found to be suboptimal:

• In 2019 an average of 71% of women at high fracture risk did not receive therapy for osteoporosis, ranging from 32% (Ireland) to 87% (Bulgaria).

• In 2010 the gap was estimated at 55% (or 10.6 million women) who were eligible for treatment but were untreated - this number has risen to 14.8 million in 2019.

• FRAX, the most commonly used risk assessment tool, is available for 24 of the 29 countries. However, its web-based usage varied widely from 49 to 41,874 sessions per million population. This indicates that the tool is underutilized in most countries.

• Waiting times between admission to hospital and surgical intervention were on average greater than 48 hours in five of the 29 countries. Early surgery within 48 hours of a hip fracture has been shown to significantly reduce mortality and increase the proportion of patients returning to their original residence.

Professor Cyrus Cooper, President of IOF, welcomed the publication of SCOPE 2021 and urged European health authorities to prioritize osteoporosis and fracture prevention:

"This important publication clearly shows that osteoporosis is a major health care burden in Europe, resulting in enormous, and growing, costs to national health care systems. As well as revealing wide discrepancies in service provision and uptake within the EU, SCOPE has exposed an unacceptable treatment gap and poor provision of post-fracture care programs to prevent secondary fractures. Despite the wide availability of treatments to prevent fractures, only a minority of patients at high risk receive treatment even after their first fracture."

"IOF joins national osteoporosis societies in Europe in calling for a Europe-wide strategy and parallel national strategies to provide coordinated osteoporosis care and to reduce debilitating fractures and their impact on individual lives and health care systems. Given the projected increase in fracture burden, urgent action must be taken."

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Further reading

Kanis JA, Norton N, Harvey NC, Jacobson T, Johansson H, Lorentzon M, McCloskey EV, Willers C, Borgström F. SCOPE 2021: a new scorecard for osteoporosis in Europe. Arch Osteoporos 16, 82 (2021). https://doi.org/10.1007/s11657-020-00871-9

SCOPE 2021 resources: https://www.osteoporosis.foundation/scope-2021

About SCOPE

The mission of the scorecard for osteoporosis in Europe (SCOPE) project is to raise awareness of osteoporosis care in Europe. SCOPE permits an in-depth comparison of the quality of care of osteoporosis across the 27 member states of the European Union (EU27), together with the UK and Switzerland (termed EU27+2).

SCOPE summarises key indicators of the burden of osteoporosis and its management in each of the member states of the European Union to draw attention to the disparities in healthcare provision that can serve in the setting of benchmarks to inform patients, healthcare providers and policy makers in the EU. This update of the original SCOPE publication and scorecard compares the original results from 2010 to data as recent as 2019. The newer data provides a more recent overview, as well as a way to compare management of osteoporosis over time, within and between the EU27+2 countries.

In developing this scorecard, the aim is to stimulate a balanced, common and optimal approach to the management of osteoporosis throughout the EU27+2.

About IOF

The International Osteoporosis Foundation (IOF) is the world's largest nongovernmental organization dedicated to the prevention, diagnosis and treatment of osteoporosis and related musculoskeletal diseases. IOF members, including committees of scientific researchers as well as 268 patient, medical and research societies, work together to make fracture prevention and healthy mobility a worldwide heath care priority. https://www.osteoporosis.foundation @iofbonehealth

 

Antarctica: How have temperatures varied since the last glacial period?

CNRS

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IMAGE: TESTING THE PROTOTYPE OF THE MINI-SUBGLACIOR EXPERIMENTAL PROBE. view more 

CREDIT: © THIBAUT VERGOZ/IPEV/LGGE/CNRS PHOTOTHÈQUE

• Scientists have established the most reliable estimates to date of past temperature variations in Antarctica.
• They highlight significant differences in behaviour between West and East Antarctica.
• This study makes it possible to test and consolidate future climate projections.

Antarctica has experienced significant temperature changes, especially since the last glacial period. An international collaboration including scientists from the CNRS1 has now challenged previously accepted estimates of these variations, using new measurements published on June 4, 2021 in Science. Their study highlights differences in behaviour between East and West Antarctica, connected in particular to differing variations in their altitude.

Surface temperatures in Antarctica have risen sharply since the last glacial period. Understanding this increase is key to understanding changes in climate at any given time and to testing our ability to model them. A study involving French scientists now provides the most reliable estimates to date of past temperature variations in Antarctica. Whereas warming since the last glacial period was until now estimated at +9 °C across the entire continent, the new measurements reveal a variation of +10 °C in West Antarctica and between +4 and +7 °C in East Antarctica.

Scientists previously estimated past temperatures using an isotopic thermometer, in other words, by analysing the ratio of different isotopic forms of water. However, the accuracy of this method relies on a calibration that is hard to implement in Antarctica. Now, two new independent methods have been developed in order to overcome this problem. The first consists in measuring the temperature in the boreholes resulting from coring2. The tremendous thickness of the Antarctic ice sheet means that records are well-preserved and can be used to reconstruct past temperatures. The second method is based on the process of snow densification, which is temperature-sensitive and can be measured by analysing the air trapped in ice cores. The two measurements gave similar results, confirming their reliability.

This work highlights the impact on temperature changes in Antarctica caused by variations in the altitude of the ice. It demonstrates the significant differences between East Antarctica, whose elevation has increased slightly since the last glacial period, and West Antarctica, where it has decreased considerably. The data was compared with climate models3 in order to better understand past temperature changes and improve confidence in future projections.

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CAPTION

Temperature probe developed at the Institute of Environmental Geosciences (OSUG, CNRS / IRD / UGA / Grenoble INP) to collect data from the EPICA borehole at Concordia.

CREDIT

© Catherine Ritz/IPEV

 

Study sheds light on pre-Columbian life in understudied area of SW Amazon

Evidence showing intensive land use for farming and fishing more than 3,500 years ago helps researchers better understand the history of a culturally significant area and is counter to the often-held notion of a pristine Amazon before Europeans arrived

UNIVERSITY OF CENTRAL FLORIDA

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IMAGE: AS PART OF THIS STUDY, THE RESEARCHERS COMMISSIONED AN ILLUSTRATION BY ARTIST KATHRYN KILLACKEY. THE ILLUSTRATION IS A REPRESENTATION OF THE PRE-COLUMBIAN LANDSCAPE AROUND 3,500 YEARS AGO, BASED ON THEIR... view more 

CREDIT: KATHRYN KILLACKEY

ORLANDO, June 2021 - A new study co-authored by University of Central Florida researchers shows that pre-Columbian people of a culturally diverse but not well-documented area of the Amazon in South America significantly altered their landscape thousands of years earlier than previously thought.

The findings, published in the journal Proceedings of the National Academy of Sciences, show evidence of people using fire and improving their landscape for farming and fishing more than 3,500 years ago. This counters the often-held notion of a pristine Amazon during pre-Columbian times before the arrival of Europeans in the late 1400s.

The study, which was conducted with experts from the UK's Northumbria University, also provides mores clues to the past of the diverse, but not well-documented, cultures that live in the area known as the Llanos de Mojos in northeastern Bolivia.

"This region has one the highest diversity of languages in the world, which reflects distinct ways of life and cultural heritage," says study co-author John Walker, an associate professor in UCF's Department of Anthropology. "We know something about the last 3,000 to 4,000 years of, say Europe or the Mediterranean, but we don't have some of that same information for the people here. That makes this an incredible story waiting to be written."

Part of the way researchers hope to write these stories is to uncover the economic practices of the distant past.

The flat, wetland landscape of the Llanos de Mojos is used for cattle ranching today, but archaeologists have noted for years the evidence from remnants of pre-Columbian raised fields and fish weirs for aquaculture. These remnants indicated the land was once used instead for farming and fishing. The archaeologists just didn't know when or how far back in time these activities started -- until now.

Previous research pointed to a date of about 300 C.E., or about 1,700 years ago. However, the new study combined expertise from multiple disciplines, such as anthropology, paleoethnobotany and paleoecology, to indicate that intensive land management started much earlier, at about 1,500 B.C.E, or about 3,500 years ago.

"This finding is important because it provides evidence that the Amazon is not a pristine wilderness but has been shaped and designed by indigenous people thousands of years before the Spanish arrived," Walker says.

This is new information for both the history of the cultures of the Amazon, which have not been studied as much as other cases, like the Mayas or Incas, and for the area, which is often thought of as an untouched world before the arrival of the Spanish.

Neil Duncan, the study's lead author and a paleoethnobotanist in UCF's Department of Anthropology, specializes in studying archaeological and paleoenvironmental plant remains to learn how humans and plants interacted in the past.

With help from the research team, Duncan extracted two, five-foot long cores of earth from two locations about 13 miles apart in the Llanos de Mojos.

By examining these cores, Duncan found corn and squash phytoliths dating as early as 1380 B.C.E and 650 B.C.E, or about 3,000 years ago. Phytoliths are microscopic silica particles from plant tissue, and the findings suggest these were crops grown in the numerous raised fields that dot the area.

Colleagues from Northumbria University in the United Kingdom examined the cores for charcoal, pollen and diatoms, which are single-celled alga indicative of aquatic environments.

Both cores showed similar trends of initial dry conditions in the oldest layers of earth, followed by increased wet conditions and increased use of wood burning, as evidenced by the presence of high diatom concentrations and charcoal concentrations, respectively. The researchers say wood burning could be for cooking, pottery, warmth and more.

"This is the first time that we've been able to show in the past how people managed their land and water resources in a coupled system," says Bronwen Whitney, an associate professor of geography and environmental sciences who led the research by the Northumbria University team. Whitney is an expert in historic environmental changes, particularly in South and Central America.

"The intensification of plant, fire and water management occurred at the same time, which emphasizes how farming or fishing were equally important to the people of the region," Whitney says.

Also of note is that the shifts in the two cores to more intensive land management happened at different periods, the researchers say.

One core, known as the Mercedes core, showed the shift to wetter conditions and increased fire use starting at 1,500 B.C.E, or about 3,500 years ago. The other, extracted from a location about 13 miles farther south and known as the Quinato-Miraflores core, showed the shift occurring at about 70 B.C.E., or about 2,100 years ago.

Since broadscale climate changes would have affected both areas at the same time, the time difference between the two cores suggests humans were purposefully engineering the land, including draining water in some areas, retaining it in others, and using trees for fuel.

"So, what's happening in the landscape is that that it's becoming wetter, and we think that some of those trees are being flooded out and so they're not as well represented," Duncan says. "And if things are getting wetter then we shouldn't see more charcoal. So, the interpretation is that we would only see these high amounts of charcoal if it's humans doing some very intentional and intensive burning."

The researchers say the next steps are to investigate the function, history, and role of the area's fish weirs and to apply new techniques to date earthworks directly and reconstruct a more detailed agricultural history for the region.

As part of this study, the researchers commissioned an illustration by artist Kathryn Killackey. The illustration is a representation of the pre-Columbian landscape around 3,500 years ago, based on their reconstruction, and details what they believe the region would have looked like at the time.

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The research was funded by a U.S.-U.K. collaborative funding partnership with the National Science Foundation (1758273) and the Arts and Humanities Research Council (AH/S00128X/1).

Study co-authors were Nicholas J.D. Loughlin and Emma P. Hocking with the Department of Geography and Environmental Sciences at Northumbria University, Newcastle upon Tyne, England.

The researchers also worked closely with the Bolivia Ministry of Cultures, Unidad Nacional de Arqueologia y Museos, Museo Regional Arqueologico "Yacuma," and researchers and students from the Universidad Mayor de San Andres in La Paz.

Duncan received his doctorate in anthropology from the University of Missouri and joined UCF's Department of Anthropology, part of UCF's College of Sciences, in 2015. Walker received his doctorate in anthropology from the University of Pennsylvania and joined UCF's Department of Anthropology in 2006.

CONTACT: Robert H. Wells, Office of Research, robert.wells@ucf.edu