The Khoisan are the 5th and oldest human race. They appeared approximately 30 000 years ago in Southern Africa, and were largely exterminated by the Dutch settlers in that area.
... like t, but with the tongue curled back) (t, th, d, dh, n)
Dental (tongue against teeth, like Spanish) (t, th, d, dh, n)
Labial (with the lips[?]) (p, ph, b, bh, ...