Why was Homo sapiens found in almost all parts of the world by 12000 years ago?

Homo sapiens' ability to adapt to different environments, develop complex social structures, and innovate technologies such as clothing, tools, and shelter contributed to their successful expansion across different regions of the world by 12,000 years ago. Additionally, their cognitive capabilities, including language and symbolic thought, allowed them to communicate, collaborate, and problem-solve, further aiding their migration and settlement in various environments.