In May 2024, researchers published a study in Science Advances about how early human ancestors used their hands. The research took place in southern Africa and focused on fossil hands from two ancient species: Australopithecus sediba, which lived about 2 million years ago, and Homo naledi, which lived around 300,000 years ago. Scientists used 3D scanning to measure bone thickness in finger fossils. This method helps show which parts of the fingers experienced more stress from daily activities. The goal of the research was to understand how these early humans lived and what tasks their hands were used for. The findings revealed that both species likely walked on two legs and also used their hands for climbing, grasping, and manipulating tools. These results challenge the idea of a simple change from “ape-like” to “human-like” hands.

The researchers found that different fingers had different bone thicknesses, which indicated diverse hand functions. This complexity suggests that early human ancestors did not follow a straight path in hand evolution. Instead, they adapted to various needs, such as moving through trees and making tools. According to scientists, hand bones respond to repeated pressure, so the thicker parts show what activities were common. Experts not involved in the study said that fossil hands are rare and that these findings offer invaluable insights into human development. The use of advanced scanning technology made it possible to study small fossils in greater detail. These discoveries provide a more nuanced understanding of how ancient humans interacted with the environment and adapted their behaviors over time.