Unlike other Mayan cities, Canc??n’s commercial power throughout the lowlands seems to be from using its strategic position at the foot of the highlands, which were a source of jade, obsidian, and other valuable commodities.

Several educational research groups are denouncing the mayor’s proposal of a system by which individual teachers would be given raises or bonuses should it be that test scores show their students’ mastery of reading skills having improved over a nine-month period.

Radiocarbon dating of fossils taken from caves on islands along southeastern Alaska’s coast suggest that at least a portion of the area was remaining ice-free during the last ice age.

Thirteen states from all regions of the country announced a plan to impose new controls on pollution from truck and bus engines in that they will jointly adopt emission limits that would be far stricter than the federal rules.

Some patients who do not respond to therapies for depression may simply have received inadequate treatment, having, for example, been prescribed a drug at a dosage too low to be effective or having been taken off a drug too soon.

A recent poll indicates that many people in the United States hold a combination of conservative and liberal political views; i.e., they denounce big government, saying government is doing too much and has become too powerful, while at the same time supporting many specific government programs for health care, education, and the environment.

The Anasazi settlements at Chaco Canyon were built on a spectacular scale with more than 75 carefully engineered structures, of up to 600 rooms each, were connected by a complex regional system of roads.

First discovered more than 30 years ago, Lina’s sunbird, a four-and-a-half-inch animal found in the Philippines and that resembles a hummingbird, has shimmering metallic colors on its head; a brilliant orange patch, bordered with red tufts, in the center of its breast; and a red eye.

Unlike battery-powered electric cars, automakers say that cars with fuel cells, which supply them with electricity, can provide driving range and performance similar to the internal combustion engine.

Although at one time children’s programming had been limited to a few hours a week, now, however, there are at least four cable networks that dedicate themselves entirely to shows produced specifically for children.