Final answer:
True, Homo erectus, an ancestor of modern humans, often had sub-adult skeletons making up roughly 40% of finds, reflecting insights into human evolution and ancient behaviors.
Step-by-step explanation:
The statement that about 40% of Homo erectus skeletons are sub-adult is True. Homo erectus, which had a prominent brow and a nose that pointed downward rather than forward, is indeed in the same family as modern humans, Homo sapiens. They represent an ancient hominin that is crucial to our understanding of human evolution. Evidence has shown that Homo erectus individuals were generally shorter and had smaller brain volumes compared to modern humans. Additionally, the discovery of Homo naledi, another ancient hominin species, was significant as it provided insight into the diversity of the genus Homo and suggested complex behaviors such as the deliberate disposal of the dead.