Final answer:
The early Pleistocene hominins included Homo habilis, Homo erectus, and Homo antecessor, with advancements in bipedalism, brain development, and tool-making.
Step-by-step explanation:
The early Pleistocene species of Homo included Homo habilis, which lived from about 2.5 to 1.4 million years ago and is known as the 'handy man' for its association with stone tools. Homo erectus evolved around 1.9 million years ago, showcasing a more efficient bipedal locomotion and larger brain, and was likely ancestral to Homo heidelbergensis. Another significant species of this era is Homo antecessor, found in Europe, and dated between 1.2 million and 800,000 years ago, which may be the ancestor of Homo heidelbergensis and is notable for its early presence in Europe.
These early hominin species show the progression and adaptation of human ancestors, with physical and neurological developments that lay the foundation for modern Homo sapiens. As such, early hominins not only adapted to bipedalism but also exhibited advancements in tool-making, brain size, and possibly cultural behaviors like deliberate burial practices, which are observed in Homo naledi.