Two South African paleontologists, Robert Broom, and his assistant, John T. Robinson, on 18th April 1947 discovered Mrs. Ples – a complete skull of an Australopithecus Africanus, in a cave at Sterkfontein, 40 kilometers to Northwest of Johannesburg, later renamed to the Cradle of Humankind World Heritage Site.
The complete pre-human skull was named Mrs. Ples by John Robinson, a name he derived from Plesianthropus Transvaalensis (Near human from the Transvaal). The fossil was dated to be 2.05 million years old. It was believed to have evolved from the Southern ape of Africa. This discovery supports Charles Darwin’s hypothesis of Africa being the birthplace of humankind.
The Cradle of Humankind World Heritage Site before then has been a site for many discoveries, and that was what prompted the quest from Robert Broom and his assistants. Upon unearthing the skull embedded firm in the rock, the duo had to use a pickaxe and dynamite to excavate the skull. It was successfully removed but broken. However, it was able to be repaired, but not all the parts were intact, and to date, Mrs. Ples was reserved at the Ditsong National Museum of Natural History in Pretoria, South Africa.
Mrs. Ples was said to be about 1.4m in height, way smaller than the modern humans. With her size of the skull, her brain was assumed to be little too. Though she walked upright but could not create tools, she was believed she had gathered her foods with sticks. Australopithecus Africanus has a flatter face than the present humans, and their incisor teeth were much smaller.
Professor Frederick E. Grine, in 2012, studied the dental morphology of the fossil. The sex of the fossil was determined using Computed Tomography scans. Observations on the canine, and molar teeth developed, concluded that the skull was of a middle-aged woman.