"Little Foot" (Stw 573) is the nickname given to a nearly complete Australopithecus fossil skeleton found in 1994–1998 in the cave system of Sterkfontein, South Africa.

[3][4] Dating of the specimen has proved controversial, with estimates ranging from 2.2 to 3.5 million years old, and its taxonomic placement is likewise disputed.

[5] In 1994 while searching through museum boxes labelled 'Cercopithecoids' containing fossil fragments, Ronald J. Clarke identified several that were unmistakably hominin.

[7] Early in 1997 two fossil preparators and assistants of Clarke, Stephen Motsumi and Nkwane Molefe, were sent to the Silberberg Grotto to try to find the matching piece of tibia from which the museum specimen had been broken.

[8] Though only the bones of both legs were visible, because they were in anatomically correct arrangement the team speculated that it could be a complete skeleton that was embedded with the face downward in the limestone.

Clarke reported this discovery six months later and explained that all previous analyses indicated that the fossil's body was apparently complete and was possibly slightly moved by ground movements and also not damaged by predators.

[9] It took Clarke and his team two full decades to fully extricate, clean, and analyze the specimen, work that was finally completed in 2017.

[10] StW 573 (Little Foot) is a nearly complete case of an Australopithecus female specimen, including the skull, that provides plenty of information on this once obscure species that helps advance perspective on them.

[14] Other fragments of the cast such as the pectoral girdle and the high ridge of StW 573's shoulder blades suggest that it had a strong upper body to support its weight while it hung from branches and climbed trees.

[14] Overall this cast shows characteristics found in both human and other primates as it exhibits signs of walking upright, early bipedalism, and locomotion through the trees.

These flowstones filled voids from ancient erosion and collapse and formed around 2.2 million years ago, however the skeleton is thought to be older.

The authors explained that this Australopithecus specimen walked upright but was also able to live in trees with the help of grasping movements.

His description, according to the known Laetoli footprints of Australopithecus and the arrangement of the foot bones discovered in the Silberberg Grotto, exhibits a high degree of compliance.

[30] He believed it seemed more likely that Australopithecus slept in the trees, similar to today's living chimpanzees and gorillas that make sleeping nests.

[31] At the end of 2008, Clarke published a reconstruction of the circumstances which allowed the fossil to remain so unusually well preserved in contrast to other bones found in the same cave, which apparently had been washed over longer periods of time in their final storage location.