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.

March 9, 2016

Next month, in April, a deep-ocean drilling project will begin off the Yucatán coast in the Gulf of Mexico. Most such oceanic drill projects are concerned with oil exploration. This isn’t your usual drill team, however. The drillers in this case come from the International Ocean Discovery Program, the National University of Mexico, and the University of Texas. And they will be drilling into Chicxulub Crater, an impact crater formed by a giant asteroid that helped kill the dinosaurs some 65 million years ago. They won’t be looking for oil; they’ll be looking for answers.

The Chicxulub Crater along the northern coast of Mexico’s Yucatán Peninsula formed when an asteroid hit the earth about 65 million years ago. Debris from the impact may have led to the extinction of the dinosaurs.
Credit: WORLD BOOK map

At the end of the Cretaceous Period, dinosaurs were the dominant land animals on the planet. Other reptiles filled the seas, and birds—descendants of dinosaurs—roamed the skies. Mammals existed, but they were far smaller and less common than today. Then, an asteroid at least 6 miles (10 kilometers) wide slammed into the Yucatán Peninsula, in present-day Mexico. The impact threw up large amounts of gas and dust into the atmosphere. This material would have blotted out the sun for many years. Plants that use sunlight to make their food would have died out, followed by the animals that ate them. With no more prey animals, large carnivores starved as well.

When the dust settled, about half of all species on Earth had gone extinct. All the dinosaurs—except birds—were dead. Only a few kinds of other reptiles survived. Mammals survived too and over time evolved to become the dominant large-bodied animals on land and in the sea.

The Yucatán asteroid formed a large impact crater, which is now partly on the peninsula and partly in the Gulf of Mexico. Tens of millions of years of plate tectonics and erosion have taken their toll on the crater, and it is barely visible in satellite images today. But the mark that it left in the rocks should still be clear.

The team plans to use a drilling ship to sample rock deep beneath the ocean floor. In drilling into the crater, scientists hope the presence (or lack) of microfossils (tiny preserved remains of ancient organisms) will teach them more about the nature of the asteroid impact and how quickly life returned to the area afterwards.

The drilling evidence may also better explain how responsible the impact was for the mass extinction at the end of the Cretaceous Period. Most scientists agree that the asteroid did most of the damage, but others argue that other causes, such as massive volcanic activity in present-day India, were more to blame. Such extinction hypotheses are not mutually exclusive, however: it may have taken more than one disaster to knock out the dinosaurs. In fact, they may even be linked. Recent studies have suggested that the Yucatán impact caused the spike in volcanism on the other side of the globe in India. Whatever the case, the drilling team will help get to the bottom of this and other stories, as well as to the bottom of the impact crater itself!

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)