a waterfall (q.v.), especially one containing great volumes of water rushing over a precipice (a very steep rock face or cliff).

a person who studies human history and prehistory through the excavation of sites and the analysis of artifacts and other physical remains.

the process of adapting wild plants and animals for human use. BLANK species are raised for food, work, clothing, medicine, and many other uses. BLANK plants and animals must be raised and cared for by humans. BLANK species are not wild

the wide-scale transition of many human cultures during the Neolithic (new stone age) period from a lifestyle of hunting and gathering to one of BLANK and settlement, making an increasingly large population possible.

heavy blackish or very dark brown timber from a mainly tropical tree

an off-white color material which is made from the teeth and tusks of animals. It has a very slight tint of yellow

to engage in the exchange, purchase, or sale of goods

is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea and is the longest river in Africa.

a mineral found in Nubia (along with copper and gold). The Nubians made BLANK weapons and BLANK-tipped spears and arrows for hunting. They made BLANK axes, which helped them cut timber and clear land for farming, and they made BLANK hoes for tilling the soil.

feathers from an ostrich.