Final answer:
The oldest stone tools, part of the Oldowan industry, date back from about 2.5 to 1.5 million years ago and are considered the first known tools of human ancestors, mainly attributed to Homo habilis.
Step-by-step explanation:
The oldest known stone tools, which are part of the Oldowan tool industry, date back from about 2.5 to 1.5 million years ago (MYA). These tools are considered crude and primitive but were crucial for early hominin survival, being utilized for cutting, scraping, and chopping. The Oldowan tools are attributed primarily to Homo habilis, although it is not clear-cut whether they were the sole creators or if Paranthropus boisei were also involved.
The Oldowan tools were preceded by later stone tool technologies, such as the Acheulean hand-axes that showed more sophistication and skill in their creation. Among the sites where these tools were found is Gran Dolina at the Atapuerca location, which provides evidence suggesting that the inhabitants used these tools, particularly Oldowan-style ones, mainly for processing and eating meat.
Overall, the emergence of these stone tool industries, including Oldowan and Acheulean, indicates significant milestones in human evolutionary history, reflecting advancements in technology, social structures, and the cognitive abilities of early hominins.