Homo naledi did not have flat foot.

The collection of 1550 Homo naledi fossil remains includes six tarsal and five metatarsal bones from the right foot, forming a nearly complete humanlike flat foot arch. The missing right medial cuneiform, however, raises our interest to explore the true structure of Homo naledi's foot arch. We hypothesize that Homo naledi does not have flat foot. To verify our hypothesis, the left medial cuneiform of Homo naledi was mirrored using three-dimensional reconstruction and virtual model analysis. Then, we defined quantities of Euler, standardized the body coordinate system of foot bone and developed a new foot arch reconstruction method based on discrete bones. The reconstructed transverse foot arch corroborated our hypothesis, thus providing biomechanical evidence for interpreting the evolution of human locomotion and bringing novel ideas to the research of the biomechanical mechanism of ankle stability.