GUINEA PIG

(species Cavia porcellus), domesticated species of South American rodent of the family Caviidae (order Rodentia). The guinea pig was domesticated in pre-Incan times and was introduced into Europe soon after the discovery of America; it has since become a popular pet and a valuable research animal. It resembles most other cavies in being stout, short legged, and about 25 cm (10 inches) long. It has small ears and no external tail. The coat may be black, tan, cream coloured, chocolate brown, reddish brown, or white, or a combination of these colours. Hair length varies. In the Peruvian variety it is long and silky; in the Abyssinian it is coarse and forms whorls; in the English, or Bolivian, it is short and smooth. The guinea pig feeds largely on grass and other green plants and, if supplied with such plants, can get along without water. It may be kept on dry rabbit or rat food, but must then have water. It is more prolific than its wild relatives and may breed three times a year, the female bearing up to eight young per litter; gestation takes 58 to 72 days. The young are well developed at birth and are weaned in about two weeks. Females are sexually mature in two or three months, but ideally should not be bred until they are about nine months old. Life spans average about three to five years, but some may live eight years or more. The economy Agriculture and other rural activities account for 80 percent of the country's employment, with less than 10 percent in industrial employment (including mining). The rest of the wage and salary earners are in the service and governmental sectors. In general, salaries are low, and the need for extra-salary means in order to eke out a livelihood remains the norm. The shortage of trained personnel is serious, and finances suffer from misappropriation and tax evasion. Many of the processing industries have been held back by inadequate supplies of raw materials. Internal production is not sufficiently high, in agriculture particularly, and the shortage of investment capital is persistent. Resources Guinea has from one-third to one-half of the world's known reserves of bauxite, plus significant reserves of high-grade iron ore at Mount Nimba and the Simandou Mountains. Alluvial gold is taken from the Niger and its tributaries, and diamond production is substantial and largely of gem-quality stones. The southeastern rain forest has some valuable species of tropical hardwoods, and both river and ocean fisheries yield large catches of food fish. Hydroelectric potential is considerable because of the high rainfall and deep gorges of the Fouta Djallon but has been only partially developed, largely to meet the demands of the alumina sector. The land Relief There are four geographic regions: Lower Guinea, the Fouta Djallon, Upper Guinea, and the Forest Region. Lower Guinea includes the coast and coastal plain. The coast has undergone recent marine submergence and is marked by rias, or drowned river valleys, that form inlets and tidal estuaries. Numerous offshore islands are remnants of former hills. Immediately inland the gently rolling coastal plain rises to the east, being broken by rocky spurs of the Fouta Djallon highlands in the north at Cape Verga and in the south at the Kaloum Peninsula. Between 30 and 50 miles (48 and 80 kilometres) wide, the plain is wider in the south than the north. Its base rocks of granite and gneiss (coarse-grained rock containing bands of minerals) are covered with laterite (red soil with a high content of iron oxides and aluminum hydroxide) and sandstone gravel. The Fouta Djallon highlands rise sharply from the coastal plain in a series of abrupt faults. More than 5,000 square miles of the highlands' total extent of 30,000 square miles lie above 3,000 feet (900 metres). Basically an enormous sandstone block, the Fouta Djallon consists of level plateaus broken by deeply incised valleys and dotted with sills and dikes, or exposed structures of ancient volcanism resulting in resistant landforms of igneous rock, such as the Kakoulima Massif, which attains 3,273 feet northeast of Conakry. The highest point in the highlands, Mount Loura (Tamgu), rises to 5,046 feet (1,538 m) near the town of Mali in the north. Upper Guinea is composed of the Niger Plains, which slope northeastward toward the Sahara. The flat relief is broken by rounded granite hills and outliers of the Fouta Djallon. Composed of granite, gneiss, schist (crystalline rock), and quartzite, the region has an average elevation of about 1,000 feet. The Forest Region, or Guinea Highlands, is a historically isolated area of hills in the country's southeastern corner. Mount Nimba (5,748 feet; 1,752 metres), the highest mountain in the region, is located at the borders of Guinea, Liberia, and Cte d'Ivoire. The rocks of this region are of the same composition as those of Upper Guinea. Drainage and soils The Fouta Djallon is the source of western Africa's three major rivers. The Niger River and several tributaries, including the Tinkisso, Milo, and Sankarani, rise in the highlands and flow in a general northeasterly direction across Upper Guinea to Mali. The Bafing and Bakoy rivers, headwaters of the Sngal River, flow northward into Mali before uniting to form the main river. The Gambia River flows northwestward before crossing Senegal and The Gambia. The Fouta Djallon also gives rise to numerous smaller rivers, such as the Fatala, Konkour, and Kolent, which flow westward across the coastal plain to enter the Atlantic. The Forest Region generally drains to the southwest through Sierra Leone and Liberia. The St. Paul River enters the Atlantic at Monrovia, Liberia, and the Moa River has its mouth at Sulima, Sierra Leone. The most common soils are laterites formed of iron and hydrated aluminum oxides and other materials that often concretize into hard iron-rich conglomerates. In the northeast, sandy brown soils predominate, while along the coast black, heavy clay soils accumulate in the backwaters. There are alluvial soils along the major rivers. Soil conservation is extremely important because most soils are thin, and the heavy rainfall causes much erosion. The people Ethnic and linguistic composition The four major geographic regions largely correspond to the areas inhabited by the major linguistic groups. In Lower Guinea the major language of Susu has gradually replaced many of the other indigenous languages and is a lingua franca for most of the coastal population. In the Fouta Djallon the major language is Pular (a dialect of Fulfulde, the language of the Fulani), while in Upper Guinea the Malinke (Maninkakan) language is the most widespread. The Forest Region contains the linguistic areas, from east to west, of Kpelle (Guerz), Loma (Toma), and Kissi. Besides the diplomatic community and a growing number of expatriate teachers and technical advisers, the number of non-Guinean residents has increased considerably since 1984. This community includes Lebanese and Syrian traders and a growing number of French engaged in agriculture, business, and technical occupations. Religions Nearly three-quarters of the population is Muslim, and a small but influential percentage is Christian, mostly Roman Catholic. A substantial minority of Guineans continue to follow local traditional religious practices.