Final answer:
Orrorin tugenensis, an early hominin species, is dated to about 6 million years ago and was discovered in Kenya in 2001. Its anatomical features suggest it walked on two legs and may be a direct ancestor of modern humans.
Step-by-step explanation:
The geological age of Orrorin tugenensis is approximately 6 million years ago (MYA). This early hominin species was discovered in Kenya in 2001 by Martin Pickford and Brigitte Senut. Its features, such as the morphology of the femur and dental structure, suggest bipedal movement and align more closely with modern humans compared to the australopithecines, even though it is much older. If Orrorin tugenensis is indeed a human ancestor, this may challenge the idea that australopithecines are in the direct line of human evolution. As more specimens are studied, further insight will be gained into the role of Orrorin in the human lineage.