Final answer:
The last common ancestor of humans, chimpanzees, and bonobos, suggested by the fossil Sahelanthropus tchadensis, lived approximately 7 million years ago. This aligns with genetic studies indicating the divergence between humans and chimpanzees occurred between 5 to 7 million years ago. The Hominidae family includes these species, all sharing a significant amount of DNA and the ability to develop language and culture.
Step-by-step explanation:
The last common ancestor of humans, chimpanzees, and bonobos is suggested to have existed around 7 million years ago (MYA). This estimate is based on the discovery of the fossil species Sahelanthropus tchadensis, found by Michel Brunet and his team. While genetic studies propose the divergence between humans and chimpanzees occurring between 5 MYA and 7 MYA, Sahelanthropus presents several features that align it closely with this timeline. The cranial capacity of Sahelanthropus is approximately 350 cubic centimeters, similar to that of a modern chimpanzee. Furthermore, the location and angle of the foramen magnum in Sahelanthropus suggest it may not have been bipedal, contrasting with the adaptations seen in later hominins like Homo habilis and Homo rudolfensis, which had larger brains and were bipedal.
The biological family Hominidae encompasses not only humans but also other great apes such as chimpanzees, gorillas, and orangutans. Members of this family share a significant percentage of their DNA, create cultures, and have the capacity for language development. The genus Homo first emerged around 2.8 million years ago, with species like Homo habilis leading the pathway towards the later emergence of Homo sapiens around 200,000 years ago with attributes such as larger cranial capacity and a more human-like physical appearance.