- Rivers have historically provided humans with fresh water, fertile land and food and have, thus, formed the bedrock of several civilisations.
- A new database, however, quantified how rivers were used to divide land and form international, national and local borders.
- Rivers make up 23 per cent of international borders, 17 per cent of the world’s state and provincial borders and 12 per cent of all county-level local borders.
- Half of South America’s borders are made by rivers, the greatest proportion of international borders made like this.
- Brazil, Colombia, Venezuela, Suriname, Guyana, French Guiana, Bolivia, Paraguay and Uruguay all have lengthy international river borders.
- North America also has sizable percentages of borders made by rivers (28 per cent), followed by Africa (26 per cent) and Europe (21 per cent).
- The Rio Grande River— that separates Mexico and Texas, United States— accounted for much of the percentage for North America.
- In Africa, rivers served as borders for several countries.
- This includes Benin, Nigeria, Senegal, Mauritania and Niger in west Africa;
- The Central African Republic, the Democratic Republic of the Congo, Tanzania and Mozambique in central Africa; and Botswana, Zambia, Zimbabwe, and Namibia in southern Africa.
- Spain, Portugal, France, Germany, Poland, Norway, Bosnia, Romania and Ukraine are among the countries in Europe whose borders are defined by rivers, the database showed.
- The continents where European powers established colonies and extended great influence tended to have more borders defined by rivers as European explorers, cartographers, politicians and diplomats found rivers to be a convenient way to divide territories.
- Asia, however, had fewer river borders (16 per cent), compared to other continents as European influence there was limited.
- This was with the exception of south Asia, where such influence was significantly prevalent until the 20th century.