1. __Bipedalism__: Standing upright on two legs freed up the hands for tool use and allowed humans to walk longer distances efficiently. Bipedalism played a crucial role in humans becoming successful hunter-gatherers.
2. __Opposable Thumbs__: The opposable thumbs allow humans to grasp objects with great precision. This adaptation revolutionized tool use and enabled humans to create more complex tools, making them better equipped for survival.
3. __Encephalization__: Humans have a large brain compared to body size, known as encephalization. The growth of the brain, and particularly the cerebral cortex, led to enhanced cognitive abilities, including problem-solving, language development, and social cooperation. The large brain has been central to human cultural and technological advancement.