While mildly interesting, why SHOULD people talk about these?
I think the better question is why this isnt more widely known like ancient greece, Rome and other places?
To answer your question: Because history
What were these civilizations achievements to math, science, agriculture, medicine etc? Heck the Mayans had brilliant achievements and that is why they are most remember, but what have these societies done?
Take the Bornu Empire, these were a people constantly at war and invading neighbors. They were a strict Islamic regime that enacted and enforced Sharia Law. They were a brutal Islamic regime that would make the Taliban proud. Despite their long recent and relatively recent history history (1800s is when they fell), they build only feudal cities, had non-existent economies and again were a brutal regime! They didn't advance human society in the slightest. Also let's not forget their helpful hand in the African slave trade. They raided villages and conquered people and then sold them off to slave traders!
Great achievements in science and technology in ancient Africa
Math
Surely only a few of us know that many modern high-school-level concepts in mathematics first were developed in Africa, as was the first method of counting. More than 35,000 years ago, Egyptians scripted textbooks about math that included division and multiplication of fractions and geometric formulas to calculate the area and volume of shapes (
3). Distances and angles were calculated, algebraic equations were solved and mathematically based predictions were made of the size of floods of the Nile. The ancient Egyptians considered a circle to have 360 degrees and estimated Î at 3.16 (
3).
Eight thousand years ago, people in present-day Zaire developed their own numeration system, as did Yoruba people in what is now Nigeria. The Yoruba system was based on units of 20 (instead of 10) and required an impressive amount of subtraction to identify different numbers. Scholars have lauded this system, as it required much abstract reasoning (
4).
Not good enough?
Astronomy
Several ancient African cultures birthed discoveries in astronomy. Many of these are foundations on which we still rely, and some were so advanced that their mode of discovery still cannot be understood. Egyptians charted the movement of the sun and constellations and the cycles of the moon. They divided the year into 12 parts and developed a yearlong calendar system containing 365 ¼ days (
3). Clocks were made with moving water and sundial-like clocks were used (
3).
A structure known as the African Stonehenge in present-day Kenya (constructed around 300 B.C.) was a remarkably accurate calendar (5). The Dogon people of Mali amassed a wealth of detailed astronomical observations (6). Many of their discoveries were so advanced that some modern scholars credit their discoveries instead to space aliens or unknown European travelers, even though the Dogon culture is steeped in ceremonial tradition centered on several space events. The Dogon knew of Saturn’s rings, Jupiter’s moons, the spiral structure of the Milky Way and the orbit of the Sirius star system. Hundreds of years ago, they plotted orbits in this system accurately through the year 1990 (6). They knew this system contained a primary star and a secondary star (now called Sirius B) of immense density and not visible to the naked eye.
