Previous Thread
Next Thread
Print Thread
#445040 08/23/12 07:38 AM
Joined: Oct 1999
Posts: 84,400
Marty Offline OP
OP Offline
The city states of the ancient Mayan empire flourished in southern Mexico and northern Central America for about six centuries. Then, around A.D. 900 Mayan civilization disintegrated.

Two new studies examine the reasons for the collapse of the Mayan culture, finding the Mayans themselves contributed to the downfall of the empire.

Scientists have found that drought played a key role, but the Mayans appear to have exacerbated the problem by cutting down the jungle canopy to make way for cities and crops, according to researchers who used climate-model simulations to see how much deforestation aggravated the drought.

"We're not saying deforestation explains the entire drought, but it does explain a substantial portion of the overall drying that is thought to have occurred," said the study's lead author Benjamin Cook, aclimate modeler at Columbia University's Lamont-Doherty Earth Observatory and the NASA Goddard Institute for Space Studies, in a statement. [Dry and Dying: Images of Drought]

Using climate-model simulations, he and his colleagues examined how much the switch from forest to crops, such as corn, would alter climate. Their results, detailed online in the journal Geophysical Research Letters, suggested that when deforestation was at its maximum, it could account for up to 60 percent of the drying. (The switch from trees to corn reduces the amount of water transferred from the soil to the atmosphere, which reduces rainfall.)

Other recent research takes a more holistic view.

"The ninth-century collapse and abandonment of the Central Maya Lowlands in the Yucat�n peninsular region were the result of complex human-environment interactions," writes this team in a study published Monday (Aug 20) in the journal Proceedings of the National Academy of Sciences.

The team, led by B.L. Turner, a social scientist at Arizona State University, concurs that by clearing the forest, the Mayans may have aggravated a natural drought, which spiked about the time the empire came to an end and population declined dramatically.

But this is just one contributing factor to their demise, Turner and colleagues write, pointing out that the reconfiguration of the landscape may also have led to soil degradation. Other archaeological evidence points to a landscape under stress, for instance, the wood of the sapodilla tree, favored as construction beams, was no longer used at the Tikal and Calakmul sites beginning in A.D. 741. Larger mammals, such as white-tailed deer, appear to have declined at the end of empire.

Social and economic dynamics also contributed. Trade routes shifted from land transit across the Yucat�n Peninsula to sea-born ships. This change may have weakened the city states, which were contending with environmental changes. Faced with mounting challenges, the ruling elites, a very small portion of the population, were no longer capable of delivering what was expected of them, and conflict increased.

"The old political and economic structure dominated by semidivine rulers decayed," the team writes. "Peasants, artisan - craftsmen, and others apparently abandoned their homes and cities to find better economic opportunities elsewhere in the Maya area."


Joined: Oct 1999
Posts: 84,400
Marty Offline OP
OP Offline

Climate Change May Have Doomed Ancient Maya, Study Finds

The mystery of the ancient Maya downfall might be solved by a rock formation that suggests climate change could have led to the civilization's demise.

Researchers from Pennsylvania State University traced a climate trail recorded in a 2,000-year-old stalagmite found in a cave in Belize, concluding that prolonged periods of drought corresponded with the disintegration of the Maya political system. The findings are published today in the journal Science.

The Maya, who originated around 2600 B.C. in current day Southeastern Mexico, grew to prominence and size during the next three millennia, building temple step-pyramids and developing highly accurate astronomical and calendar systems. Why some of their larger cities were abandoned a thousand years ago is largely a mystery. Though weather shifts have been proposed previously, the stalagmite findings may offer the data that was lacking, said Douglas Kennett, the lead study author.

"We lucked into very good material to work with, to develop a very detailed climate record that is anchored chronologically in a way that other records haven't been able to," Kennett, a professor of anthropology at Penn State in State College, Pennsylvania, said in a phone interview.

Previous climate records, taken from lake bed samples, would have provided a picture of rainfall levels in 10 year to 30 year increments, with potential errors as much as a century off.

Stalagmite Record
Kennett and his team located the 2,000-year old stalagmite in Belize's Yok Balum Cave, about 1 mile away from Uxbenka, a major Mayan site, that recorded rainfall records within 6 month increments and with errors within a decade. Stalagmites form when mineral deposits drip down from stalactites, the icicle looking formations that descend from the cave's ceiling. These deposits contain oxygen isotopes that reflect rainfall amounts above the cave, according to the study.

The researchers then matched those findings with a time line of events from Mayan stone monuments and carvings that were highly detailed in recounting the society's history.

The scientists found that a wetter period corresponded with an increase in food production, and population growth, from 450 to 660 AD. During this time, cities such as Tikal, Copan and Caracol expanded, and the ancient civilization reached the pinnacle of its power, covering all of Guatemala, Belize, parts of Honduras, El Salvador and Mexico.

A drying period occurred during the next four centuries, punctuated by droughts. Mayan records show an increasing number of wars being fought in this period, and eventually larger cities gave way to smaller settlements, Kennett said.

'Losing Control' "You have a loss of a large number of these polities," he said. "You get this major reduction in the production of these stone monuments -- that's a reflection of kings losing control and losing power at these primary centers."

The final blow came with a 90-year drought that started in 1010 AD, leading to the decline of the last of the major Mayan centers.

Rosemary Joyce, an archeology professor at the University of California, Berkeley who didn't work on the study, said the information will be valuable.

"Anything that produces an annual, or a very fine grained record that allows us to monitor indirectly the broader climate, is going to help us get a better model," Joyce said in an interview. "In that sense, this is important research."

Click here for the rest of the story in Bloomberg News

Stalagmites & Hieroglyphs: Investigating the Maya Demise

Maya region

You think you have interesting work, and indeed you may, but chances are it doesn't involve hieroglyphs, fieldwork at a Belize geological site, a 2,000-year-old stalagmite or coordinating a team of diverse experts across oceans to help solve a centuries-old mystery that may hold important lessons for us today.

But if this work, which is that of environmental archaeologist Douglas Kennett, sounds a little bit like Indiana Jones, it is in fact, often a slog. For his late 2012 published research related to the role of climate in the collapse of the Classic Maya (300 to 1000 C.E.), his team extracted and analyzed thousands of samples from a 2,000-year-old stalagmite.

"It was intensive, intensive work," says the Penn State professor. "In my lab there were students drilling samples 20 to 30 hours a week for a year."

The students were drilling tiny trenches in a stalagmite Kennett's team harvested along with nine others in the Yok Balum cave in Belize. Stalagmites form when water drips onto cave floors and leaves mineral deposits, which build up over time into rock towers. The stalagmite used for Kennett's study was about 2 feet (56 cm) long and had grown in a spot 55 yards (50 m) or so inside the cave. Extracting it and nine others like it was not easy. Stalagmites are very solid and heavy, and the researchers had to carry their specimens by light of headlamp, through narrow, craggy passages. What's more, the team was working in a part of the cave that hadn't yet been mapped.

The stalagmites of Yok Balum cave, Belize

Stalagmites have stories to tell, with chemical signatures locked inside internal concentric rings. The chemical profiles can provide information about what was happening with the climate at a given time. For example, traces of a relatively rare, heavier oxygen isotope suggest drier conditions. (Isotopes are variants of chemical elements — they have the same number of protons and electrons, but their neutron numbers vary.) Kennett's team used uranium-thorium dating to determine the stalagmite's age and that it had grown continuously for 2,000 years, i.e., without interruptions due to non-climate environmental factors, which would have distorted the climate record.

In the lab

Drilling in .1 millimeter increments into a cross-section 50 centimeters (about 20") in length, Kennett's students ultimately delivered 4,000 samples of stalagmite powder. Their process entailed drilling the trench, carefully using a flat edge to collect the powder sample and tip it into a vial, and just as carefully marking the vial with accurate and thorough data. Then, the students used compressed air to thoroughly clean the cross-section surface before the next drilling. It was slow and tedious work.

But it yielded great results. The analysis of early samples came out "in much more spectacular fashion than I ever envisioned," said Kennett. A research partner, the Swiss Technological Institute, stepped in to analyze the remaining samples. In the end, Kennett's team had an annual rainfall record (showing "wet" and "dry" cycles) for a 2,000-year period. The group had produced the most detailed view to date of climate trends during the period of Classic Maya collapse. Scientists had debated the role of climate in the demise of the Classic Mayans; now, here was evidence that climate might very well have played a significant role.

A stucco frieze monument in Caracol.

Long dry spell

The evidence showed that the deterioration of this complex civilization coincided with a decades-long drought after a period of prosperity, which itself had been enabled by a long period of high rainfall.

"The main finding was that a prolonged drought contributed to the collapse of Classic Mayan civilization," Kennett says. "But the story isn't complete without recognizing the preceding period of high rainfall, which was followed by a population expansion and proliferation of political centers."

How did the researchers know what was going on socially and politically at the time? They relied in part on the work of anthropological linguist Martha Macri, a specialist in hieroglyphs who has been studying and translating hieroglyphs inscribed on Mayan monuments for decades and directs the Maya Hieroglyphic Database Project at the University of California, Davis.

A stalagmite in Yok Balum cave, Belize.

Kennett's team used the hieroglyphic database to quantify three types of events that signal political instability — war, events related to war (e.g., taking war captives) and the rate at which Mayan rulers commissioned new monuments (Monuments were built to honor new rulers, royal marriages, etc.). The "war index" showed that increased status rivalry, shifting strategic alliances and more battles tended to follow periods of drought. The big picture showed that the entire trajectory toward collapse occurred during a drying of the Mayans' world. Specifically, there was a drying trend between 660 and 1000 C.E. and an extended drought between 1020 and 1100 C.E.

"You can think about it almost as a trap. For 200-300 years there were conditions that promoted expansion of the population ... [Then] you see a gradual downturn towards drought that started stressing the complex system," Kennett said. "And that's where warfare indices come in. Some of the most remarkable amounts of writing come towards the end of the Classical period. ... The society was already in decline and it was stressed further by a gradual drying trend. Then at the end, there were several dramatic droughts."

Kennett and his colleagues see relevance to their study in a 16th-century drought that occurred in the upper Yucatan and discussed it in their paper. "Historical accounts link this [16th-century] drought to reduced agricultural productivity, famine, disease, death and population relocation," they wrote.

"Some estimates suggest that drought-related agricultural disaster caused nearly a million deaths in Mexico in 1535 C.E." The chain of events in Mexico provides a historic analog to the events in and around Belize, the researchers argue. This will be an area for future study, Kennett said, along with studies that can shed more light on how relevant the Belize stalagmite findings are for the Mayan lowlands in general.

Kennett and his colleagues theorize that shifts in climate related to the Mayan collapse may have been driven by the migration of the Intertropical Convergence Zone — a broad band of low pressure near the equator — along with changes in El Nino frequency.

Yok Balum cave and the ancient city of Uxbenka.

Concert master

It turns out that solving a 2,000-year old mystery can take the concerted efforts of many experts. The Yok Balum paper, published in Science in November 2012, had 18 authors. In all there were 25 or so researchers involved, Kennett said, plus their students, from nine institutions.

It wasn't always easy to coordinate and manage the work, schedules and agendas of a large and geographically widespread team, he said. But the clear upside is that there are so many scientists available to build upon the Yok Balum data and earlier datasets.

"In the Maya region there is a lot of opportunity to integrate records," Kennett says. "Because there have been a large number of long-term archaeological projects at many Maya cities ... there is a lot of data to start with."

The Yok Balum study has assumed a life of its own, with several researchers taking the investigation in new directions or using the data to inform their own studies, Kennett says. For example, James Baldini of Durham University in England incorporated the data into his five-year study, the HURRICANE Project, which seeks to build a detailed picture of Atlantic hurricanes over the last 500 years, as a way to help predict future hurricane activity in our own changing climate.

And in April, Kennett had a paper published in Nature Scientific Reports linking the Maya Long Count calendar with the European calendar, based on a study using carbon-14 dating of carved wooden door beams from the Maya city of Tikal in Guatemala.

Then and Now

Mainstream news outlets and the blogosphere took notice of Kennett's study when Science published it in November 2012. As you may recall, the Mayans were on people's minds around that time; it was hard to escape talk of predictions — supposedly based on the Mayan Long Count calendar — that the world would experience cataclysmic change on Dec. 21. But climate change is a source of more enduring anxiety and it is most significant that Kennett's research findings seemed to offer obvious parallels to our own climate crisis.

"There are cautionary tales there," Kennett said. "The Maya are not us. We have a much more complicated situation. If someone were a climate change denier, he would say, 'The Maya are completely different, we have technologies the Maya could never have imagined and we can more easily adapt.' And to a certain degree, that's true. But the interaction and articulation between the social and economic processes on the ground and environmental and climatic processes — looking at those relationships is valuable.

"You had people living in Maya region that were living day-by-day within the context of changing climatic conditions and trying to make decisions about when and how much to plant. This was difficult as climatic conditions changed at the end of the Classic Period. And that had major sociopolitical repercussions."

That's the lesson that is valuable for us today, he says.


Joined: Oct 1999
Posts: 84,400
Marty Offline OP
OP Offline

Why the Maya Fell: Climate Change, Conflict-And a Trip to the Beach?

Latest evidence hints at a cautionary tale for modern civilization, expert says.

In a wet period, Maya farms thrived, and an empire flowered, studies say.

Maya Empire, seemingly swallowed by the jungle after centuries of urban, cultural, intellectual, and agricultural evolution.

What went wrong? The latest discoveries point not to a cataclysmic eruption, quake, or plague but rather to climate change. And faced with the fallout, one expert says, the Maya may have packed up and gone to the beach.

But first came the boom years, roughly A.D. 300 to 660. At the beginning of the so-called Classic Maya period, some 60 Maya cities-each home to between 60,000 and 70,000 people-sprang up across much of modern-day Guatemala, Belize, and Mexico's Yucatán Peninsula. (Explore an interactive map of key Maya sites.)

Surrounded by pyramids, plazas, ball courts, and government buildings, the urban Maya discussed philosophy, developed an accurate solar-year calendar, and relished a thick, bitter beverage made from cacao beans: the world's first hot chocolate.

Farmers, too, were riding high, turning hillsides into terraced fields to feed the burgeoning population.

Then came the bust, a decline that lasted at least two centuries. By 1100 the residents of once thriving Maya cities seem to have just up and left. But where did they flee to, and why?

In the 19th century, when explorers began discovering the overgrown ruins of "lost cities," theorists imagined an immense volcanic eruption or earthquake or superstorm-or maybe an empire-wide pandemic. (Related: "Maya Mystery Solved by 'Important' Volcanic Discovery?")

But today scientists generally agree that the Maya collapse has many roots, all intertwined-overpopulation, warfare, famine, drought. At the moment, the hottest field of inquiry centers on climate change, perhaps of the Maya's own doing.

(Also see "Climate Change May Have Killed Off Maya Civilization, Study Says.")

Flowering With the Rain

The latest Maya climate-change study, published Friday in the journal Science, analyzes a Belizean cavern's stalagmites-those lumpy, rocky spires on cave floors-to link climate swings to both the rise and fall of the empire.

Formed by water and minerals dripping from above, stalagmites grow quicker in rainier years, giving scientists a reliable record of historical precipitation trends. One sample used in the new study, for example, documents fluctuations as far back as 2,000 years ago.

Among the trends revealed by the Belizean stalagmites: "The early Classic Maya period was unusually wet, wetter than the previous thousand years," according to study leader Douglas Kennett, an environmental anthropologist at Pennsylvania State University. "During this time, the population proliferated," aided by a surge in agriculture.

During the wettest decades, from 440 to 660, cities sprouted. All the hallmarks of Maya civilization- sophisticated political systems, monumental architecture, complex religion-came into full flower during this era.

(Read about the rise and fall of the Maya in National Geographic magazine.)

Climate Shift Sparks Conflict

But the 200-year-long wet spell turned out to be an anomaly. When the climate pendulum swung back, hard times followed.

"Mayan systems were founded on those [high] rainfall patterns," Kennett said. "They could not support themselves when patterns changed."

The following centuries, from about 660 to 1000, were characterized by repeated and, at times extreme, drought. Agriculture declined and-not coincidentally-social conflict rose, Kennet says.

The Maya religious and political system was based on the belief that rulers were in direct communication with the gods. When these divine connections failed to produce rainfall and good harvests, tensions likely developed.

Within the scant 25 years between 750 and 775, for example, 39 embattled rulers commissioned the same number of stone monuments-evidence of "rivalry, war, and strategic alliances," according to Kennett's study.

But times would get even harder.

The stalagmite record suggests that between 1020 and 1100 the region suffered its longest dry spell of the last 2,000 years. With it, the study suggests, came Maya crop failure, famine, mass migration, and death.

By the time Spanish conquistadors arrived in the 16th century, inland Maya populations had decreased by 90 percent, and urban centers had been largely abandoned. Farms had become overgrown and cities reclaimed by forest.

(Take a Maya quiz.)

A Cautionary Tale?

The collapse, though, wasn't exactly all natural. To some extent, the Maya may have designed their own decline.

"There were tens of millions of people in the area, and they were building cities and farms at the expense of the forest," climate scientist Benjamin I. Cook said.

Widespread deforestation reduced the flow of moisture from the ground to the atmosphere, interrupting the natural rain cycle and in turn reducing precipitation, says Cook, of NASA's Goddard Institute for Space Studies and the Lamont-Doherty Earth Observatory.

According to computer simulations Cook ran for a study published in Geophysical Research Letters this past August, the localized drying decreased atmospheric moisture by 5 to 15 percent annually. Even a 10 percent decrease is considered an environmental catastrophe, he says.

Add this to the broader drying trend and the situation becomes dire-a cautionary tale for modern society, according to Cook. Today, as more and more forestland is turned into farms and cities, and as global temperatures continue to rise, we may risk the same fate that befell the Maya, he says.

But, according to Arizona State University professor of environment and society B.L. Turner, "that's the kind of oversimplification we're trying to get away from. The Mayan situation is not applicable today-our society is just so radically different now."

Lure of the Beach

In a study published in August by the journal Proceedings of the National Academy of Sciences, Turner attempts to correct some common misconceptions, beginning with the idea that Maya civilization vanished after the conquistadores arrived.

"It didn't cease to exist; there are still today Mayan people in the area. The culture, the traditions have been maintained," he said. But the cities, historically, have not-and that's odd.

Throughout global history, he said, "rarely can you find a large sustained population that just left and never came back," Turner said. The closest analogue he can think of is the sudden, and final, abandonment of Cambodia's Angkor Wat complex in the 15th century.

Turner's study concludes that the natural environment recovered rather quickly after the dry centuries. Why, then, didn't the Maya reclaim their glorious cities?

Turner points to the coasts. Fleeing starving, warring inland cities, many Maya made a beeline for the shore. Trade also shifted, from overland paths to coastal routes, he suggests.

With life relatively comfortable on the coast, the inland Mayan cities may have simply been forgotten, Turner says. No catastrophic earthquake, no plague, no curse, but rather a gradual migration to the beach, where life was a bit mellower.

That is, until the Spanish arrived.

More: See National Geographic pictures of Maya ruins and artifacts >>

National Geographic

Maya Collapse explained as 100 year drought

An aerial view of the coral reef and deep cave that make up the famous diving spot of the Blue Hole in the Caribbean Sea, off the coast of Belize.

Belize's Famous 'Blue Hole' Reveals Clues to the Maya's Demise

The ancient Mayan civilization collapsed due to a century-long drought, new research suggests.

Minerals taken from Belize's famous underwater cave, known as the Blue Hole, as well as lagoons nearby, show that an extreme drought occurred between A.D. 800 and A.D. 900, right when the Mayan civilization disintegrated. After the rains returned, the Mayans moved north - but they disappeared again a few centuries later, and that disappearance occurred at the same time as another dry spell, the sediments reveal. [In Photos: Stunning Sinkholes]

Although the findings aren't the first to tie a drought to the Mayan culture's demise, the new results strengthen the case that dry periods were indeed the culprit. That's because the data come from several spots in a region central to the Mayan heartland, said study co-author André Droxler, an Earth scientist at Rice University.

Rise and decline From A.D. 300 to A.D. 700, the Mayan civilization flourished in the Yucatan peninsula. These ancient Mesoamericans built stunning pyramids, mastered astronomy, and developed both a hieroglyphic writing system and a calendar system, which is famous for allegedly predicting that the world would end in 2012.

But in the centuries after A.D. 700, the civilization's building activities slowed and the culture descended into warfare and anarchy. Historians have speculatively linked that decline with everything from the ancient society's fear of malevolent spirits to deforestation completed to make way for cropland to the loss of favored foods, such as the Tikal deer.

The evidence for a drought has been growing in recent years: Since at least 1995, scientists have been looking more closely at the effects of drought. A 2012 study in the journal Science analyzed a 2,000-year-old stalagmite from a cave in southern Belize and found that sharp decreases in rainfall coincided with periods of decline in the culture. But that data came from just one cave, which meant it was difficult to make predictions for the area as a whole, Droxler said.

The main driver of this drought is thought to have been a shift in the intertropical convergence zone (ITCZ), a weather system that generally dumps water on tropical regions of the world while drying out the subtropics. During summers, the ITCZ pelts the Yucatan peninsula with rain, but the system travels farther south in the winter. Many scientists have suggested that during the Mayan decline, this monsoon system may have missed the Yucatan peninsula altogether.

Deep history To look for signs of drought, the team drilled cores from the sediments in the Blue Hole of Lighthouse lagoon, as well one in the Rhomboid reef. The lagoons surrounded on all sides by thick walls of coral reef. During storms or wetter periods, excess water runs off from rivers and streams, overtops the retaining walls, and is deposited in a thin layer at the top of the lagoon. From there, all the sediments from these streams settle to the bottom of the lagoon, piling on top of each other and leaving a chronological record of the historical climate.

"It's like a big bucket. It's a sediment trap," Droxler told Live Science.

Droxler and his colleagues analyzed the chemical composition of the cores, in particular the ratio of titanium to aluminum. When the rains fall, it eats away at the volcanic rocks of the region, which contain titanium. The free titanium then sweeps into streams that reach the ocean. So relatively low ratios of titanium to aluminum correspond to periods with less rainfall, Droxler said.

The team found that during the period between A.D. 800 and A.D. 1000, when the Maya civilization collapsed, there were just one or two tropical cyclones every two decades, as opposed to the usual five or six. After that, the Maya moved north, building at sites such as Chichen Itza, in what is now Mexico.

But the new results also found that between A.D. 1000 and A.D. 1100, during the height of the Little Ice Age, another major drought struck. This period coincides with the fall of Chichen Itza.

The findings strengthen the case that drought helped usher in the long decline of the Mayan culture.

"When you have major droughts, you start to get famines and unrest," Droxler said.

Live Science

The Collapse Explained

"The ancient Mayan civilization collapsed due to a century-long drought," - that's what new research suggests. According to a study by archaeologists at Rice University, sediments found in the Belize Blue Hole near the center of Lighthouse Reef show that extreme drought may be the leading cause of the civilization's collapse.

The director of the Institute of Archaeology, Dr. John Morris told us via phone that this development complements the research he and his team are conducting in the Caves here in Belize and that this theory is only one of many.

Dr. John Morris
"There are many theories that explain the collapse of the ancient Maya civilization and one of them is that of environmental degradation or in some sense severe dry period of drought that affected the Maya quite considerably. It's one of several theories and one that has been examined quite recently in detail. The evidence that we are acquiring comes from core deposits that we retrieve from lagoons and lakes and also from tests done on stalagmites in caves and primarily because what those show is that running through test on the stalagmites, it shows that a severe dry period took place sometime around that same period between 700 and 900 AD and the evidence is remarkable because those caves for example the one in the blue hole and also when you look at the coring done at Lake Peten in Tikal, it shows also too that there was significant dry periods."

According to Morris the period of drought is recorded to have occurred between 700 and 900 AD.

Researchers found that during this period, there were only one or two tropical cyclones every two decades, as opposed to the usual five or six.

Environmental conditions and weather patterns are also being studied based on this evidence to validate the drought theory.

Channel 7

Joined: Oct 1999
Posts: 84,400
Marty Offline OP
OP Offline

The Maya practiced sustainable agriculture that supported dense populations well beyond the Classic period.

Classic ancient Maya

For years, archaeologist Anabel Ford has been arguing the case that the ancient Maya knew well how to manage their tropical forest environment to their advantage, eventually sustaining large populations even beyond the time when many archaeologists suggest the Maya declined and abandoned their iconic Classic period pyramidal and temple constructions and monumental inscriptions during the 8th and 9th centuries CE.  She challenges the popular theories long held by many scholars that the Maya declined because of overpopulation and deforestation from increased agricultural production, perhaps aggravated by draught and climate change.  

“In the past there was no extensive deforestation,” states Ford.*

At the base of her reasoning stands years of research related to the ancient practice of the Maya in cultivating ‘forest gardens’, a method of sustainable agroforestry that employs an agricultural methodology called the Milpa Cycle—the creation of a polycultivated, tree-dominated, biodiverse landscape by dispersed smallholder farmers, employing natural cycles and maximizing the utility of the native flora and fauna. Having its roots even before the rise of the Preclassic Maya, it worked by sequencing an area from a closed canopy forest to an open field. When cleared, it was dominated by annual crops that transformed into a managed orchard garden, and then back to a closed canopy forest in a continuous circuit. “Contrary to European agricultural systems developed around the same period, these fields were never abandoned, even when they were forested,” says Ford. “Thus, it was a rotation of annuals with succeeding stages of forest perennials during which all phases received careful human management.”   

She explains the process and its implications in detail in her new book, The Maya Forest Garden: Eight Millennia of Sustainable Cultivation of the Tropical Woodlands, co-authored with Ronald Nigh, a professor at the Centro Investigaciones y Estudios Superiores en Antropología Social (CIESAS) in Chiapas, Mexico. The book summarizes years of research evaluating archaeological, paleoenvironmental, agricultural, botanical, ecological and ethnographic and historical data from Guatemala, Mexico, and Belize, including a focus on the large Maya center of El Pilar.

“Ecological, agricultural, and botanical research on the Maya forest demonstrates that it is in fact a variegated garden dominated by plants of economic value, and thus highly dependent on human interaction,” says Ford. Thus, “the co-creation of the Maya and their forest environment was based on a strategy of resource management that resulted in a landscape called the Maya “forest garden.”


elpilarmilpadiversityA Maya forest garden. Courtesy BRASS/El Pilar

elpilarmilpacycleThe Milpa Cycle, from maize field to perennials and back to the forest. Courtesy BRASS/El Pilar

Moreover, Ford points to the Milpa Cycle as being responsible for producing much of the visible fabric of the ancient Maya jungle ‘backdrop’, including the Maya landscape of today—a forest that is in a real sense itself a creation and ‘monument’ of the Maya people.  “The Maya forest, once thought to be a wild, pristine jungle, is, in reality, the result of prehistoric, colonial, and recent human activities,” write Ford and Nigh in their book.* 


elpilarmosaiclandscape2Courtesy Exploring Solutons Past: The Maya Forest Alliance


In other words, by managing and shaping the forest landscape elements through the Milpa Cycle into a human-sculpted environment beneficial in terms of the food, shelter, medicinal and other material needs for sustaining ever-increasing populations, the Maya became the actual creators of their tropical environment—in essence, the architects of the jungle itself. Most significantly, because of its sustainable, renewing techniques, the Milpa Cycle became a key to the longevity of the Maya civilization long after the Classic period ‘collapse’. Ford and Nigh conclude: “When political crises struck Classic Maya society, the population largely retired to the forest garden, leaving elite centers abandoned.”*


The book, The Maya Forest Garden: Eight Millennia of Sustainable Cultivation of the Tropical Woodlands, is published by Left Coast Press and can be purchased at the Left Coast Press website

*Ford, Anabel and Nigh, Ronald, The Maya Forest Garden: Eight Millennia of Sustainable Cultivation of the Tropical Woodlands, Left Coast Press, June 2015.


Popular Archaeology

Joined: Oct 1999
Posts: 84,400
Marty Offline OP
OP Offline

Archaeologists uncover new clues to Maya collapse

Using the largest set of radiocarbon dates ever obtained from a single Maya site, archaeologists have developed a high-precision chronology that sheds new light on patterns leading up to the two major collapses of the ancient civilization.

Archaeologists have long puzzled over what caused what is known as the Classic Maya collapse in the ninth century A.D., when many of the ancient civilization's cities were abandoned. More recent investigations have revealed that the Maya also experienced an earlier collapse in the second century A.D.—now called the Preclassic collapse—that is even more poorly understood.

University of Arizona archaeologist Takeshi Inomata and his colleagues suggest in a new paper, published in the Proceedings of the National Academy of Sciences, that both collapses followed similar trajectories, with multiple waves of social instability, warfare and political crises leading to the rapid fall of many city centers.

The findings are based on a highly refined chronology developed by Inomata and his colleagues using an unprecedented 154 radiocarbon dates from the archaeological site of Ceibal in Guatemala, where the team has worked for over a decade.

While more general chronologies might suggest that the Maya collapses occurred gradually, this new, more precise chronology indicates more complex patterns of political crises and recoveries leading up to each collapse.

"What we found out is that those two cases of collapse (Classic and Preclassic) follow similar patterns," said Inomata, the paper's lead author and a professor in the School of Anthropology in the UA College of Social and Behavioral Sciences. "It's not just a simple collapse, but there are waves of collapse. First, there are smaller waves, tied to warfare and some political instability, then comes the major collapse, in which many centers got abandoned. Then there was some recovery in some places, then another collapse."

Using radiocarbon dating and data from ceramics and highly controlled archaeological excavations, the researchers were able to establish the refined chronology of when population sizes and building construction increased and decreased at Ceibal.

Archaeologists excavate the royal palace of Ceibal, which was burned during the Classic Maya collapse in the ninth century. Credit: Takeshi Inomata/University of Arizona

University of Arizona anthropology professor Daniela Triadan excavates the collapsed facade of the royal palace of Ceibal, which was burned during the Classic Maya collapse in the ninth century. Credit:Takeshi Inomata/University of Arizona

While the findings may not solve the mystery of why exactly the Maya collapses occurred, they are an important step toward better understanding how they unfolded.

"It's really, really interesting that these collapses both look very similar, at very different time periods," said Melissa Burham, one of three UA anthropology graduate students who co-authored the paper. "We now have a good understanding of what the process looked like, that potentially can serve as a template for other people to try to see if they have a similar pattern at their (archaeological) sites in the same area."

Inomata and his UA colleagues—anthropology professor Daniela Triadan and students Burham, Jessica MacLellan and Juan Manuel Palomo—worked with collaborators at Ibaraki University, Naruto University of Education and the Graduate University for Advanced Studies in Japan, and with Guatemalan archaeologists and students.

Radiocarbon dating was done at Paleo Laboratory Company in Japan and at the Accelerator Mass Spectrometry Laboratory in the UA Department of Physics.

"Radiocarbon dating has been used for a long time, but now we're getting to an interesting period because it's getting more and more precise," said Inomata, who also is an Agnese Nelms Haury Chair in Environment and Social Justice at the UA. "We're getting to the point where we can get to the interesting social patterns because the chronology is refined enough, and the dating is precise enough."

Article Source: University of Arizona

Popular Archaeology

Ancient Mayan civilisation 'was WIPED OUT by deforestation'
Carbon reserves in Central American soils are still affected by the trees they were chopping down more than 1,000 years ago. The downfall of the mysterious people who flourished in the steamy jungles of present-day southern Mexico, Belize and Guatemala has been debated for years. Climate change has been blamed. Trees use sunlight to absorb CO2 from the atmosphere through photosynthesis and store it as carbon in the form of wood. The study of sediments from three lakes supports this theory. It shows the amount of time the greenhouse gas remained stored in soils in Guatemala and the Yucatan Peninsula was shortened by deforestation undertaken by the Maya.

Joined: Oct 1999
Posts: 84,400
Marty Offline OP
OP Offline
Elites' preference for maize led to the collapse of the Maya civilization

The preference for a maize-centric diet by Mayan elites may have left the ancient civilization more vulnerable to climate change, according to new research.

To better understand the relationship between diet and the collapse of the Maya civilization, researchers analyzed the remains of 50 Maya people from burial sites surrounding an ancient Maya city in Belize. The oldest remains were dated to the Middle Preclassic period, between 735 and 400 B.C., while the youngest remains were dated to the Terminal Classic, between 800 and 850 A.D.

To decipher the dietary habits of the Maya people, scientists analyzed the carbon and nitrogen isotope values in preserved bone collagen. The findings showed the youngest remains had higher levels of carbon isotopes from a group of plants that includes the Maya staple crop maize. The concentration was highest among the remains of elite members of the Maya civilization.

Isotope rations among the remains of both elites and commoners from the Middle Preclassic period revealed a diverse diet. Over time, however, maize became more popular among elites.

As the Maya population grew and social stratification intensified, a dichotomy in eating habits developed during the Terminal Classic period. The remains of people living farther from the city center had lower levels of maize-derived carbon in their bones. People living in the city ate more maize, researchers found.

"Our results show a pattern of highly restricted stable nitrogen and carbon isotopes for elite individuals in the Late and Terminal Classic, which corresponds to a hyper-specialized maize-based diet that persisted through the final abandonment of the site," Claire Ebert, a paleontologist and geochemist at Pennsylvania State University, said in a news release.

Ebert and her colleagues suggest the agricultural practices of the Maya civilization shifted to meet the demands of city elites. Intensified monoculture practices made the civilization less able to adapt to periods of drought and other types of climatic stress.

"Population expansion and anthropogenic environment degradation from agricultural intensification, coupled with socially conditioned food preferences, resulted in a less flexible and less resilient system," Ebert said.

Researchers published their findings this week in the journal Current Anthropology.

"The study speaks to the importance of diet in the resilience and decline of ancient societies and contributes to our understanding of vulnerability to climate change among modern traditional farming communities as well as industrialized nations," Ebert said.


Joined: Jul 2019
Posts: 2
I found an interesting paper and it seems to fit with Mayan Collapse discussion. The Collapse of the Classic Maya Kingdoms of the Southwestern Pet�n: Implications for the End of Classic Maya Civilization, details pls click:

Joined: Oct 1999
Posts: 84,400
Marty Offline OP
OP Offline
Severe Cyclones May Have Played a Role in the Maya Collapse

Sediment cores from the Great Blue Hole reveal that a series of extreme storms hit the region after 900 A.D.

Why the once great Maya civilization withered away is still a matter of debate among historians, archaeologists, and geoscientists. The leading theory is that the Maya suffered a series of severe droughts around 800-1100. New evidence suggests there may have been another reason: severe tropical storms.

Researchers studying past climate records in the Caribbean found that storm activity was weak and predictable up to about 900. At that point, storms became more intense and unpredictable. The stress of dealing with the highly variable and intense storms, in addition to battling drought, may have pushed the Maya over the edge, according to research published in Scientific Reports in July.

Now Dominik Schmitt of Goethe University in Frankfurt, Germany, and colleagues have reconstructed past storms in the region going back 2,000 years. The researchers recovered and studied an 8.5-meter-long sediment core from the Great Blue Hole on Lighthouse Reef off the coast of Belize.

Upon analyzing the results, Schmitt's team found evidence of the AMO going back to 300. According to Schmitt, this provides statistical proof that the AMO, along with ENSO, modulates hurricane activity in the southwestern Caribbean.

Click here to read the rest of the article in the Smithsonian Magazine

Link Copied to Clipboard
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29
Cayo Espanto
Click for Cayo Espanto, and have your own private island
More Links
Click for exciting and adventurous tours of Belize with Katie Valk!
Who's Online Now
0 members (), 182 guests, and 0 robots.
Key: Admin, Global Mod, Mod
Forum Statistics
Most Online7,413
Nov 7th, 2021 HELP! Visitor Center Goods & Services San Pedro Town Message Board Lodging Diving Fishing Things to Do History Maps Phonebook Belize Business Directory Picture of the Day

The opinions and views expressed on this board are the subjective opinions of Ambergris Caye Message Board members
and not of the Ambergris Caye Message Board its affiliates, or its employees.

Powered by UBB.threads™ PHP Forum Software 7.7.5