In 2005, turning 80, he wrote of a life enriched by "serendipity, coincidence, synchronism, eureka moments."
"You go to search for something -- an odd tree -- and you find something else, something that may prove to be even more important than that which you had set out to examine! This is the essence of serendipity," he wrote, describing a 1945 visit to a cave in Limpopo to see a twisted yellowwood tree when he was 20 years old.
Kneeling in the sandy soil to get a better look at the tree, he felt something hard and pulled out an ancient stone tool.
He launched an archaeological dig in the cave, which he later named Mwulu's Cave. It became a significant site, casting light on the earliest artistic activity by predecessors of humans. Some 3,000 stone tools were excavated from the place.
One of the University of Witwatersrand's most eminent scientists, nominated three times for a Nobel Prize, Tobias was initially drawn to genetics after his sister, Valerie, died because of diabetes. He gained five degrees, including in medicine, genetics and paleoanthropology, and he headed the anatomy department from 1959 to 1990.
He was involved in the excavation of the Sterkfontein Caves, northwest of Johannesburg, one of South Africa's most important fossil sites and a place where numerous hominid fossils have been found. He was also part of the research on hominids in the Olduvai Gorge in Tanzania, collaborating with British archaeologist Louis Leakey on the identification of one the early hominids, homo habilis, in 1964.
In 1995, Tobias announced the discovery of Little Foot, an almost complete hominid skeleton unearthed at Sterkfontein by a team he led.
He leaves behind no family, but said he was proud of a different gift to humanity: a cultural legacy for the thousands of students he taught and inspired.
"I am married to my work, the [University of Witwatersrand] medical school and the anatomy department at Wits. I also have a large family of around 10,000 children -- my students," he said in a 2010 interview.
"I like to believe that I have given something valuable to every one of them, and I can tell you quite honestly that almost every one of them has given something very valuable to me, and I remember them as my own family," he said in comments recorded on the Cradle of Humankind website
Tobias was one of the group of scientist who in 1953 exposed the 1912 Piltdown Man as a hoax, explaining that an orangutan lower jawbone had been buried with a human skull and passed off as a specimen of ancient man.
On Thursday, tributes to Tobias poured in. On Twitter, Derek Hanekom, South Africa's deputy minister for science and technology, called him "a brilliant man, a visionary, a pioneer, a legend! A gentleman!"
Tobias, who was born in Durban, South Africa, on Oct. 14, 1925, learned to read at 3. But commenting on his intellect in a 2005 interview, he said only that "I must have inherited a tolerably well-developed nervous system. But what one makes with a well-developed nervous system depends on one's environment and education. My schooling and my self-education as an inveterate reader from an early age must have used the nervous system my genes gave me to good effect.
"The genes lay down a range of possibilities, but your environment, your teaching, your education select among those possibilities."
He was an outspoken critic of apartheid who occasionally was warned by South African authorities that his research grants might be withdrawn if he failed to toe the line. "But I felt it was my duty to speak out on the meaning of race, and did so on every possible occasion," he said in 2005.
Above all, Tobias celebrated people -- all people.
"I love people. I love my students. I love the world around me of humanity -- black, white, male, female. They are among my passions.
"People are fun. I love dinner parties and braaivleis [barbecues] and camping out with my students at Sterkfontein and Makapansgat and sing-songs around the campfire. Part of me is quite an ordinary sort of chap. I love quite simple things."
-- Robyn Dixon
Photo: South African paleoanthropologist Phillip Tobias on Jan. 16, 2006. Credit: Alexander Joe / AFP/Getty Images