Natural Environment Reference

In physics, radioactivity refers to the spontaneous emission of electromagnetic energy and subatomic particles in certain substances. Radioactive release of energy happens when an unstable atomic nucleus transforms (decays) into a more stable configuration. This process can occur naturally in some types of matter, or can be induced artificially. Handling radioactive matter requires caution, as electromagnetic energy can potentially cause damaging mutations when it comes into contact with living cells.

A pleasant smelling small shrub with hairy branches and groups of yellow flowers found across the American Great Basin. It provides nesting and cover to small birds and jackrabbits. The Navajo make yellow dye from the flowers.

A long-eared mammal known for its prominent front teeth and powerful hindlegs, with which it hops and leaps rather than runs. The most common rabbits in the Southwest are desert cottontails and mountain cottontails. The mountain cottontail often is associated with thickets, sagebrush and cliffs, while the desert cottontail prefers open plains, foothills and low valleys of the arid Southwest.

Although jackrabbits are also common throughout the Southwest, they are not really rabbits. Instead they are considered hares and prefer semi-open, grassy plains and deserts as opposed to higher, rougher country.

Also known as cougar or mountain lion, the puma is a large wild cat native to the Western Hemisphere. Pumas can be found in a variety of habitats across North and South America, including forests, mountains, swamps, or deserts. Adult pumas are brown in color and reach a length of about 4 feet (1.2 meters), not including their long tail, and their weight averages 136 pounds (62 kg).

A ponderosa pine is a large coniferous evergreen tree, with long pine needles, that can grows over 70 feet in height. Ponderosa are found throughout the western United States and in Canada. The tree is easily identifiable by its bark, which is often yellow or red with large plates separated by crevices, making ponderosa bark look kind of like puzzle pieces. Ponderosa pines are generally found in mountainous regions, and in the U.S. Southwest, ponderosa can be found in open, park-like stands above 6,000 feet in elevation.

A large or powerful creature that preys on smaller and weaker creatures. The term typically refers to a carnivorous animal that hunts other animals for survival. Common predators in the Southwest are wolves, mountain lions, and birds of prey such as the eagle or the hawk. However, depending on the context, a predator can also be a human who victimizes people who don't possess the agency to resist him or her. In addition, some institutions such as government agencies, large corporations, and prominent financial institutions, among others, are said to be predatory because of their exploitative policies or business practices.

Belonging to the squirrel family of rodents, the prairie dog is a very social burrowing rodent who lives in colonies, called towns, that can include up to several hundred individuals. Communication occurs quickly throughout the town, as prairie dogs communicate via a range of physical contact, vocalization, and drumming patterns they beat into the earth's surface with their paws. The prairie dog language is believed to be the most advanced form of natural animal language.

Prairie dog numbers have declined drastically due to shootings, plague cycles, and poisoning.

Porcupines are large herbivorous rodents with a coat of sharp spines, also known as quills. These quills are actually strands of hair coated with layers of keratin, a form of protein found in skin. The quills function both as camouflage but also as protection, as the hard sheath of keratin tapers into barbed points, making the porcupine appear sort of like an elongated pincushion.

Also known as the North Star, the Pole Star is actually three stars whose light merge to create a single bright glow, the brightest star of the constellation Ursa Minor. This star appears stationary in the sky and comprises the end point of the handle of the Little Dipper constellation. As the Little Dipper's handle always points "up" or "north," it is often used for navigation in the Northern Hemisphere.

A cluster of seven stars located outside of our solar system. Historically, the Pleiades were very important to many world cultures. For people in the Northern Hemisphere, when the Pleiades rise above the eastern horizon, it marks the beginning of spring and the beginning of planting season. For the Ancient Greeks and other mariners of the ancient world, the appearance of the Pleiades in the night sky signified sailing season in the Mediterranean.

The Pleiades are also known as the Hard Flint Boys in some versions of Navajo tradition. According to these versions of Navajo mythology, after the earth was separated from the sky, Black God had a cluster of seven stars, the Hard Flint Boys, on his ankle. Every time Black God stamped his foot, the Flint Boys would jump up to his knee, hip, shoulder and finally his forehead, where eventually they remained. When this happened, it revealed to everybody that Black God was in charge of the sky. In fact, today, we still can see the Flint Boys, namely the Pleiades, high in the sky in autumn and winter.