September 21, 2017

Two days ago, on September 19, a powerful 7.1-magnitude earthquake struck central Mexico, collapsing buildings and killing more than 240 people in Mexico City, the capital, and in the states of Guerrero, México, Morelos, Oaxaca, and Puebla. The earthquake struck on the anniversary of a catastrophic 1985 earthquake that killed some 10,000 people in central Mexico. The quake followed another deadly temblor that hit southern Mexico earlier in September 2017.

Rescue workers call for quiet as they search a collapsed building in the Mexico City neighborhood of La Condesa following a powerful 7.1-magnitude earthquake on Sept. 19, 2017. The earthquake toppled buildings and killed more than 240 people in the region. Credit: © Alejandro Cegarra, Bloomberg/Getty Images

The earthquake’s epicenter was near the small Puebla city of Atencingo, about 75 miles (120 kilometers) southeast of Mexico City. The prolonged tremor hit at 1:14 p.m. local time—just two hours after an annual earthquake drill in Mexico City—shaking buildings and frightening people into the streets. Structures collapsed in several cities, obscuring the panicked survivors in dust clouds amid the blaring din of alarm sirens.

Emergency responders rushed to the first scenes of destruction. Unstable rubble and electric power outages hampered rescue efforts, and widespread damage meant many ravaged places went hours without help. Military personnel and civilian volunteers aided emergency workers as they searched through the night for survivors. Sniffer dogs followed human scents, and workers pleaded for silence, hoping to hear the calls of people trapped beneath the destruction. Many people were saved, but the body count rose quickly as splintered wood, shattered masonry, and chunks of concrete were frantically removed. Many people remain missing amid the devastation, and the disaster’s death toll—245 as of this morning—will almost certainly rise.

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On Sept. 19, 2017, a powerful earthquake hit central Mexico, killing more than 240 people in the Federal District of Mexico City and in the states of Guerrero, México, Morelos, Oaxaca, and Puebla. Credit: WORLD BOOK map

In Mexico City, more than 90 people have died, including 21 children and 5 adults killed when an elementary school collapsed in the city’s southern Coapa district. More than 70 people were killed in Morelos, just south of Mexico City, and more than 40 died in the epicenter state of Puebla. On the slopes of Popocatépetl volcano southeast of Mexico City, a church collapsed in the village of Atzitzihuacán, killing 15 people. Throughout the region, scores of buildings fell, ruptured gas lines sparked fires, and falling debris crushed cars on the streets.

Like the earthquake earlier in September in southern Mexico, Tuesday’s temblor struck near the Middle America Trench, a zone in the eastern Pacific Ocean where one slab of Earth’s crust, the Cocos Plate, is sliding beneath the North American Plate—a geological process called subduction. The Middle America Trench is part of the so-called Ring of Fire, an area of high seismic and volcanic activity that encircles the Pacific Ocean. The United States Geological Survey (USGS) issued an orange alert (the second-highest threat level) after Tuesday afternoon’s quake, warning of significant casualties and extensive and widespread damage. The alert was part of the USGS PAGER (Prompt Assessment of Global Earthquakes for Response) system that informs emergency responders, the media, and government and aid agencies of the scope of a potential disaster.

On Sept. 19, 1985, an 8.0-magnitude temblor killed some 10,000 people in Mexico City and nearby areas. About 400 buildings in the capital were destroyed in that disaster, and thousands of others suffered damage. Since then, Mexico has enacted tougher building codes and safety standards—moves that no doubt saved many lives 32 years later.

September 12, 2017

Just before midnight on Thursday, September 7, a powerful earthquake caused death and destruction in southern Mexico. The 8.1-magnitude quake, the strongest in the region in decades, centered just off the Pacific coast states of Chiapas and Oaxaca. The temblor (another word for earthquake in both English and Spanish) toppled numerous structures and killed 96 people. Many people remain missing, however, and the death toll will almost certainly rise.

Emergency crews search the collapsed ruins of buildings in Juchitán de Zaragoza, Mexico, after a powerful earthquake struck the area late on Sept. 7, 2017. At left stand the surviving white arches of the city’s damaged palacio municipal (city hall). Credit: © Pedro Pardo, AFP/Getty Images

The earthquake’s epicenter was in the Gulf of Tehuantepec just off the southern Mexican coast. The coastal city of Juchitán de Zaragoza bore the brunt of the earthquake’s destruction. Hundreds of buildings were destroyed there, and many thousands were damaged, including Juchitán’s historic palacio municipal (city hall). In the early hours of Friday, September 8, emergency crews, federal police, and soldiers began pulling the dead and the living from the rubble of wrecked buildings as aftershocks rocked the area, causing further damage and panic. Since then, many damaged buildings have been cleared, but strong aftershocks continue and many structures remain too unstable to enter. More than 160 area municipalities have declared states of emergency, and many thousands of people still lack electric power, running water, and phone service.

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Late on Sept. 7, 2017, a powerful earthquake caused damage and killed people in the southern Mexican states of Oaxaca, Chiapas, and Tabasco. Credit: WORLD BOOK map

The quake struck near the Middle America Trench, a zone in the eastern Pacific Ocean where one slab of Earth’s crust, the Cocos Plate, is sliding beneath the North American Plate—a geological process called subduction. The Middle America Trench is part of the so-called Ring of Fire, an area of high seismic and volcanic activity that encircles the Pacific Ocean. The United States Geological Survey (USGS) issued a red alert (highest threat level) after Thursday night’s quake, warning: “High casualties and extensive damage are probable and the disaster is likely widespread.” The alert was part of the USGS PAGER (Prompt Assessment of Global Earthquakes for Response) system that informs emergency responders, the media, and government and aid agencies of the scope of a potential disaster.

Last week’s earthquake was felt throughout southern Mexico and neighboring Guatemala. Some 500 miles (800 kilometers) away in Mexico City, the capital, structures swayed and earthquake alarms caused a mild panic. Many of the city’s residents carry vivid memories of the deadliest quake in Mexican history, an 8.0-magnitude temblor in 1985 that killed some 10,000 people in the city and nearby areas. About 400 buildings in Mexico City were destroyed in that disaster, and thousands of others suffered damage. Since then, Mexico has enacted tougher building codes and safety standards.

July 21, 2017

In a study published in late June, scientists detailed the probable discovery of a new bird species: the blue-winged Amazon parrot. Its scientific name is Amazona gomezgarzai in honor of its discoverer, Miguel Gómez Garza, an ornithologist at the Autonomous University of Nuevo León in Mexico. Gómez Garza first saw the blue-winged Amazon parrot in 2014 in the Yucatán Peninsula while gathering information for his book, Parrots of Mexico. He and other researchers studied the unusual parrots for almost three years. The bird’s distinctive behavior, plumage, and DNA led Gómez Garza to declare the animal a new species.

Male (right) and female blue-winged Amazon parrots wait to scare other birds from nearby trees. Credit: Tony Silva (licensed under CC BY 4.0)

As its name suggests, the blue-winged Amazon parrot has blue-tinged wing feathers. It also has bright red plumage sprouting from its forehead and an all-green front. Other parrot species in the Yucatán have white plumage in front. Blue-winged Amazon parrots stand about 9.8 inches (25 centimeters) tall.

Like other parrots, the blue-winged Amazon parrot is noisy and sociable and lives chiefly in forested areas. The bird is very active with a seemingly limitless store of energy. The parrots live in flocks of fewer than 12 individuals, and mated pairs stay together with their offspring. The thing that truly sets the blue-winged Amazon parrot apart from other parrots, however, is its “singing voice.” Parrots are known for their ability to mimic sounds—Polly want a cracker? But this parrot goes a step further and imitates the call of a hawk. Now, hawks often feed on parrots, so why would the parrot want to imitate its predator? Scientists think the parrots do it to scare other birds from surrounding trees, leaving more seeds, fruit, and flowers for the parrots to eat. Scientists are still waiting, however, to see how the calls effect the nerves of other blue-winged Amazon parrots.

Through DNA research, the scientists believe that blue-winged Amazon parrots evolved from white-fronted parrots (Amazona albifrons) that were native to Yucatán about 120,000 years ago. Not all scientists are convinced, however, that white-fronts and blue-wings are actually different species. More study and genetic work is needed before blue-winged Amazon parrots can be conclusively labeled as a new species.

If the blue-winged Amazon parrot is in fact a distinct species, it is also an extremeley rare one. Scientists estimate their population at just 100 birds in the wild. The parrots face such human threats as deforestation and the illegal pet trade. Thankfully, plans are already in the works to save the parrots and their habitat.

May 5, 2017

Today, May 5, is Cinco de Mayo, a holiday celebrated in Mexico and in many communities throughout the United States. Cinco de Mayo is Spanish for Fifth of May. Many people know that Cinco de Mayo commemorates the victory of a Mexican army over a French army at the Battle of Puebla on May 5, 1862. But few people know much about the battle itself, which took place near Puebla, a city in central Mexico, during a French invasion of Mexico. Mexican forces won the Battle of Puebla, but their victory did not stop the French from taking control of Mexico. A French-supported government led by Emperor Maximilian ruled Mexico from 1864 until 1867, when Maximilian was killed and the Mexican republic was restored.

People participate in a reenactment of the Battle of Puebla in Mexico City, the capital of Mexico. The battle took place on May 5, 1862, and is remembered by the holiday of Cinco de Mayo (Spanish for Fifth of May). Credit: © Jorge Uzon, AFP/Getty Images

In April 1862, a force of some 6,000 French troops marched inland from the port city of Veracruz, intending to take Mexico City, the nation’s capital. Puebla lay along the route to the capital, and Mexican General Ignacio Zaragoza assembled about 4,800 troops nearby to stop the French advance. On April 28, the French won an initial battle at Acultzingo Pass leading to Puebla. Zaragoza then withdrew to Puebla, which was protected by fortifications on two large hills—Guadalupe and Loreto—and other defenses.

Mexican President Benito Juárez (seen here in a statue in central Mexico) was forced from power in 1864, but he returned to lead Mexico in 1867. Credit: © AA World Travel Library/Alamy Images

On May 5, 1862, French artillery began bombarding Puebla’s defenses, and an infantry assault soon followed. The French attack failed under the concentrated fire from Puebla’s defenders. A second attack also failed, but the French refused to quit and launched a third attack. It too failed. Suffering heavy casualties (people killed and wounded), the French called off the assault. Mexican cavalry then attacked the French as they attempted to withdraw, inflicting still more casualties. With the battle lost, the French eventually retreated to Orizaba, a city midway between Puebla and Veracruz.

The French suffered nearly 500 casualties at Puebla, including more than 100 killed in action. Mexican losses were about 85 dead and more than 100 wounded. Despite the defeat, the French recovered quickly. After receiving about 30,000 reinforcements the following autumn, the French renewed their march toward Mexico City. The French won the second Battle of Puebla in May 1863 and then pushed on to take Mexico City. Mexican President Benito Juárez was forced into hiding, and the French installed Archduke Maximilian of Austria as emperor of Mexico in 1864.

The French installed Archduke Maximilian as emperor of Mexico in 1864. Rebel Mexican forces captured and executed Maximilian in 1867. Credit: Andrew Burgess, Library of Congress

After the bloody American Civil War ended in the spring of 1865, the United States threatened to intervene to remove the French from Mexico. The French then began withdrawing their forces in 1866. At the same time, a resistance movement led by Juárez increased attacks on the French and Mexican troops loyal to Maximilian.

In February 1867, Maximilian and his army withdrew north of Mexico City to the city of Querétaro, where Mexican rebels soon besieged them. In May, Maximilian was betrayed by one of his officers and captured by rebel troops. The emperor—who had ordered all Juárez supporters caught bearing arms to be shot—was himself executed by firing squad on June 19, 1867. The Mexican republic was then restored, and Juárez again became president.

January 25, 2017

On Sunday, January 15, Mexican farmer and indigenous activist Isidro Baldenegro López was gunned down at his uncle’s home in Coloradas de la Virgen, a town in southern Chihuahua state. For years, Baldenegro had run a nonviolent campaign to protect the pine and oak forests of the western range of the Sierra Madre. In 2005, his efforts earned him the prestigious Goldman Environmental Prize for North America. Unfortunately, his efforts also led to death threats and his eventual murder. Baldenegro was 51 years old.

Goldman Environmental Prize winner Isidro Baldenegro López (left) stands with Tarahumara elders in Coloradas de la Virgen, Chihuahua. Baldenegro was murdered on Jan.15, 2017. Credit: Goldman Environmental Prize

Baldenegro was the second Goldman prizewinner murdered in the past year. In March 2016, gunmen killed 2015 Goldman winner Berta Cáceres, an environmental activist who led her Lenca people of Honduras against a proposed dam. Baldenegro, a leader of the Tarahumara people, defended the old growth forests of the Sierra Madre Occidental against drug traffickers and loggers. The Tarahumara are one of the largest indigenous groups in North America.

Baldenegro’s environmental actvism was passed down from his father, Julio Baldenegro, who, in 1986, was also murdered for opposing logging in the mountain forests. Isidro formed his first advocacy group in 1993 and began organizing efforts to stop logging—efforts that have met with little success. Violence erupted in his region of Chihuahua in 2006 as the government stepped up its campaign against drug cartels. Already fighting against loggers, Baldenegro and others then faced armed gangs who cleared trees to plant marijuana on the mountainsides.

Death threats had forced Baldenegro to maintain a low profile for several years, and he had moved away from his home in the Guadalupe y Calvo Municipality at the southern tip of Chihuahua. He had only recently returned to visit the home of an uncle—where he was killed. Four other activists were also killed in Guadalupe y Calvo over the past year. The deaths of Cáceres, Baldenegro, and others highlight the dangers activists face in Latin America, where big business and criminal interests often conflict with local communities.

The Sierra Madre Occidental range hosts diverse ecosystems with snow-covered peaks and four separate canyons, each deeper than Arizona’s Grand Canyon. The forests and rivers are home to numerous species of amphibians, fish, reptiles, and migratory birds, as well as many threatened or endangered species of goshawks, macaws, owls, and parrots.

January 13, 2017

In December 2016, an exhibition of the work of Mexican artist Frida Kahlo opened at the Dalí Museum in St. Petersburg, Florida. The museum, home to a broad collection of the works of Spanish artist Salvador Dalí, is showing more than 60 of Kahlo’s works through the middle of April 2017. “Frida Kahlo at the Dalí” includes 15 paintings, 7 drawings, and numerous photographs. The exhibit extends outdoors, where a collection of flowers and plants replicates Kahlo’s own gardens at la Casa Azul (the Blue House), her home in Mexico City. Casa Azul, the Coyoacán District house where Kahlo was born, lived much of her life, and died, is now home to the Museo Frida Kahlo.

The Salvador Dalí Museum in St. Petersburg, Florida, is hosting a Frida Kahlo exhibition until April 2017. Credit: © Shutterstock

Both Kahlo (1907-1954) and Dalí (1904-1989) lived their lives much as they created their art, operating just beyond what might be considered “normal” or expected. Both created dreamlike images, and they shared a contemporary and linguistically similar—if geographically distant—art world. Dalí, firmly positioned within the Surrealist art movement, differed from Kahlo, however, whose works—while sometimes crossing the border into the surreal—offered harsher and revealing truths that often dealt with physical and emotional suffering. Kahlo rejected Surrealism and considered her works as real as her life itself. Nonetheless, French author and critic André Breton, the founder of Surrealism, took great interest in Kahlo’s work and described her art as “a bomb wrapped in a ribbon.”

Frida Kahlo’s 1945 Autorretrato con changuito (Self Portrait with Monkey) is among her works on display at the Dalí Museum. Credit: Autorretrato con changuito (1945), oil on composite board by Frida Kahlo; Museo Dolores Olmedo, © 2016 Banco de México Diego Rivera and Frida Kahlo Museums Trust (Artists Rights Society)

At the age of 15, Kahlo was severely injured in an accident while riding on a bus in Mexico City. From then on, she was crippled and lived in constant pain. She underwent about 35 operations, including the amputation of one leg in 1953. Unable to pursue her dream of becoming a doctor, Kahlo taught herself to paint. In 1929, she married fellow Mexican artist Diego Rivera. Their stormy relationship added fuel to the fire of Kahlo’s art. Most of her roughly 200 paintings are self-portraits, often painted with jarring colors and odd spatial relationships. Many of her pictures include startling symbolic images and elements from Mexican history.

Frida Kahlo in 1941. Credit: © Hulton Archive/Getty Images

The pairing of Kahlo’s works with those of the Surrealist master Dalí may seem at odds on the surface, but an exploration of their mutual eccentricities puts them hand-in-hand in a walk through the enduring art of the 1900’s.

October 26, 2015

Hurricane Patricia, seen on Friday, October 23, 2015, was the strongest storm ever recorded in the Western Hemisphere. (NOAA)

On October 21, a small tropical storm formed from a system of thunderstorms in the Pacific Ocean off the coast of Mexico. Just two days later, that storm became became Hurricane Patricia, the strongest storm ever recorded in the Western Hemisphere, with winds of 200 miles (320 kilometers) per hour. Soon after, the storm hit coastal villages in Jalisco in western Mexico. Then, less than a day later, Hurricane Patricia fizzled out and was gone. The storm’s rapid development and disappearance caused scientists to ask new questions about extreme weather’s connection to worldwide climate cycles.

Hurricanes are powerful, swirling storms that begin over warm seas. The storms then move westward, often toward the poles. When a hurricane hits land, it can cause great damage through fierce winds, torrential rain, flooding, and huge waves crashing ashore.

Hurricanes require a special set of conditions, including ample heat and moisture, that exist primarily over warm, tropical oceans. For a hurricane to form, there must be a sufficiently warm layer of water at the top of the sea. This warm seawater evaporates into the air. The moisture then condenses (changes into liquid), forming clouds. As the moisture condenses, it releases heat that warms the air, causing the air to rise. The warm, rising air creates a region of relatively low atmospheric pressure. (Atmospheric pressure is the weight of the air pressing down on a given area.)

Air tends to move from areas of high atmospheric pressure to areas of low pressure, creating wind. Earth’s rotation can cause the wind to swirl as it blows into a low-pressure area. As the swirling winds increase in speed, more ocean water evaporates and condenses. The moisture releases more heat, further warming the storm’s core. The warm air rises faster, increasing surface wind speeds, and so on. This cycle, called a positive-feedback loop, continues to strengthen the hurricane. Only when friction between the air and the water surface becomes great enough will a hurricane weaken.

Scientists still aren’t sure why such hurricanes as Patricia intensify so quickly. In Patricia’s case, some of the energy may have come from exceptionally warm surface waters in the region, caused by this year’s developing El Niño event. El Niño is part of the interaction between Earth’s atmosphere and the tropical waters of the Pacific Ocean. An El Niño occurs about every two to seven years, and it can affect climate throughout the world. The El Niño of 2015 is shaping up to be one of the strongest events on record. Studying Hurricane Patricia’s development will help meteorologists make better predictions concerning extreme weather in regions affected by El Niño.

Despite Patricia’s incredible intensity, it caused relatively little damage to Mexico. It struck an area of the country where few people live. Evacuation efforts were also effective. The hurricane’s enormous strength quickly waned over land, as tall coastal mountains helped beak up the storm. Overall, fewer than 10 people died and damages were not expected to exceed $200 million.

May 5, 2015

Across much of North America, Mexicans and Mexican Americans will be celebrating Cinco de Mayo today. Cinco de Mayo (Spanish for Fifth of May) celebrates the Mexican victory at the Battle of Puebla on May 5, 1862.

Performers in Mexico City celebrate Cinco de Mayo with a reenactment of the Battle of Puebla. (© Jorge Uzon, AFP/Getty Images)

After the Mexican War (1846-1848) with the United States, and a civil war that ran from 1858 to 1861, the treasury of the Mexican government was nearly bankrupt. The president of Mexico, Benito Juárez, issued a two-year moratorium on the payment of European loans in 1861. In 1862, France, Spain, and the United Kingdom all sent ships to Mexico. Spain and Britain negotiated a settlement with the government of Mexico. France, however, was unwilling to accept Mexico’s promise to pay its debt in future. The French representative ordered troops into Mexico.

To reach Mexico City, the French army had to cross the state of Puebla. The Mexican general Ignacio Zaragoza faced off against French general Charles de Lorencez in the town of Puebla. The French believed that the battle would be easy. The French army had 6,000 well-trained troops. The Mexicans had 4,000 troops, some of whom were untrained farmers armed with implements. Overconfidence proved the undoing of the French. After several unsuccessful assaults, they were forced to retreat, with the Mexican cavalry in pursuit. It was a definitive victory for the Mexican army.

The victory was short lived. It caused the French emperor Napoleon III to send 30,000 additional French troops. They arrived in Mexico in 1863 and quickly defeated the Mexican army.  Juárez formed a government in exile in the north of Mexico. Napoleon then appointed the Austrian Archduke, Maximilian, to be emperor of Mexico in 1864.

With the end of the American Civil War in 1865, the United States was able to give military assistance to Mexico, in keeping with the Monroe Doctrine, a policy that supported the independent nations of the Western Hemisphere against European interference. Napoleon III withdrew his forces from Mexico in 1866, leaving Maximilian without support. The Mexican emperor was executed by firing squad on June 19, 1867. Juárez returned to Mexico City and was president of the Mexican Republic until his death in 1872.

Cinco de Mayo is celebrated everywhere in Mexico, but it is especially popular in the state of Puebla. It is even more popular in the United States, especially in regions with a large Mexican-American population. It has become a day to celebrate Mexican heritage.

Additional World Book articles:

• Hispanic Americans
• Research guide (Hispanic Americans)

August 28, 2014

A Mayan city was recently rediscovered in southeastern Mexico, near El Mirador in Guatemala. (World Book map)

Archaeologists have rediscovered the “lost” Maya city of Lagunita, along with another previously unknown city called Tamchen. Both cities are hidden deep in the jungle of the Calakmul Biosphere Reserve in southeastern Mexico, near the border with Guatemala. The cities flourished around A.D. 600 to 950, near the end of what scholars call the Classic Period of Maya civilization. Among the ruins, archaeologists found plazas and the remains of what are thought to be palaces and stone pyramids up to 65 feet (20 meters) high. The scientists believe there are several other Maya cities in the region that remain to be discovered.

Archaeologists have known of the existence of Lagunita since the 1970′s, when American explorer Eric Von Euw returned from the region with drawings of an ancient Maya city he had discovered. However, Von Euw never published a description or the exact location of his discovery in the vast jungle reserve. Ivan Sprajc and his colleagues of the Slovenian Academy of Sciences and Arts in Ljubljana were able to determine the location of the lost city of Lagunita as well as Tamchen by examining aerial photographs of the region. The jungle is so thick in this region that even large stone buildings can barely be seen beneath the dense foliage. The team mapped areas at each site that covered around 30 acres (12 hectares). Residential areas surrounding these city centers would have covered even more ground. At Tamchen, scientists found over 30 deep stone chambers, called chultuns, that the Maya used to collect and store rain water, suggesting a sizable population lived in the city.

Ruins of an ancient Maya temple stand at Palenque, in the state of Chiapas, Mexico. The temple was built about A.D. 650. The Maya civilization reached its height in Mexico and Guatemala during the Classic Period, between around A.D. 250 and 900. Ruins found recently in southeastern Mexico date to that period. (© Ales Liska, Shutterstock)

One building at the main entrance to Lagunita has a facade featuring a doorway in the shape of the mouth of a terrible monster. The facade may represent the entrance to a sacred portion of the city associated with the underworld. The entrance closely resembles a building facade drawn by Von Euw in the 1970’s, so the scientists are certain it is the same site. The team plans to conduct excavations at the site in the future. The excavations may help scholars determine why Maya civilization collapsed at the end of the Classic Period.

Beginning in the A.D. 800′s, the Maya stopped building large pyramids and temples. Over the following decades, they abandoned their major cities in the Guatemala lowlands and other regions. Some experts have linked the collapse to a combination of factors, including overpopulation, disease, exhaustion of natural resources, crop failures, warfare between cities, and the movement of other groups into the Maya area.

Additional World Book articles:

• Archaeology

June 24, 2013

Pyramids, palaces, ball courts, and houses from an ancient Maya city overgrown by centuries of thick jungle vegetation have been discovered in a remote area of southeastern Mexico by scientists from Mexico’s National Institute of Anthropology and History. Occupied from about A.D. 600 until 900, the city has been newly renamed Chactun. The scientists reported that the city, which covered about 54 acres (22 hectares), is the first ancient Maya complex found in a now heavily forested area of Campeche province in the western Yucatán Peninsula. Also found at the site were plazas and altars as well as stone monuments called stelae. The name “K’inch B’ahlam,” which may refer to one of the city’s rulers, was carved on one stele.

The scientists discovered Chactun while examining aerial photographs of the area. Visiting the site required hacking their way along paths once used by loggers and workers who tapped the area’s rubber trees.

The Maya civilization reached its peak from about A.D. 250 to 900. During that time, known as the Classic Period, it was centered in the tropical rain forest of the lowlands of what is now northern Guatemala. By about 900, most of the Maya abandoned the lowlands and moved to areas to the north and south, including Yucatán and the highlands of southern Guatemala. In those areas, they continued to prosper until Spain conquered almost all of the Maya in the mid-1500′s. Scholars are still trying to discover the reasons for the collapse of Classic Maya society in the lowlands. Some experts point to a combination of such factors as overpopulation, disease, exhaustion of natural resources, crop failures, warfare between cities, and the movement of other groups into the Maya area.

In a study published in November 2012, a research team headed by environmental archaeologist Douglas Kennett of Pennsylvania State University concluded that a 100-year drought played a major role in the collapse of the Classic Maya society. The drought, which plagued the lowlands from 1020 to 1100, had followed a drying period that began in about 660. According to Kennett, Maya writings from this period link the drought to widespread famine, disease, and wars, among other disruptive events.

Additional World Book article include:

• Chichén Itzá
• Copán
  
• Mexico (History of)
• The Ancient Maya: Deciphering New Clues (a special report)
• Archaeology (1924) (a Back in Time article)