Birds are a group of endothermic vertebrates, characterised by feathers, toothless beaked jaws, the laying of hard-shelled eggs, a high metabolic rate, a four-chambered heart, and a lightweight but strong skeleton. Birds live worldwide and range in size from the 5 cm bee hummingbird to the 2.75 m ostrich. They rank as the class of
Three quarters of the planet Earth is covered by water. A majority of the planet's solid surface is abyssal plain, at depths between 4,000 and 5,500 metres (13,100 and 18,000 ft) below the surface of the oceans. The solid surface location on the planet closest to the centre of the orb is the Challenger Deep,
Wildlife traditionally refers to undomesticated animal species, but has come to include all plants, fungi, and other organisms that grow or live wild in an area without being introduced by humans. Wildlife can be found in all ecosystems. Deserts, forests, rain forests, plains, grasslands, and other areas including the most developed urban sites, all have
The Safe Drinking Water Act (SDWA) is the principal federal law in the United States intended to ensure safe drinking water for the public. Pursuant to the act, the Environmental Protection Agency (EPA) is required to set standards for drinking water quality and oversee all states, localities, and water suppliers who implement these standards. SDWA
The Philippines' location on the Pacific Ring of Fire and close to the equator makes the Philippines prone to earthquakes and typhoons, but also endows it with abundant natural resources and some of the world's greatest biodiversity. The Philippines has an area of approximately 300,000 square kilometers (115,831 sq mi) Population is more than 100 million and still
Clarissa Harlowe Barton was a pioneering nurse who founded the American Red Cross. She worked as a hospital nurse in the American Civil War, and as a teacher and patent clerk. Barton is noteworthy for doing humanitarian work at a time when relatively few women worked outside the home. She had a relationship with John
