Why do humans have wrists?

Wrists, a vital component of human upper limbs, serve multiple essential functions:

Mobility and Dexterity: The wrist joint, with its range of motion that enables bending and rotation (flexion, extension, abduction, adduction, and circumduction), allows for an extensive array of movements. Such flexibility is crucial in performing an array of daily tasks and intricate hand activities, from writing to grasping objects.

Support and Balance: Wrist bones, along with carpal ligaments, provide structural support and stability to the forearm and hand. They help bear weight, distribute mechanical forces, and withstand pressure exerted during activities such as lifting or gripping objects.

Muscle Attachments: Wrists facilitate muscle attachments that enable hand and finger movements. Muscles in the forearm connect and insert onto the wrist bones, allowing for the intricate control of hand and finger positioning and actions.

Passage for Structures: The carpal tunnel, a pathway surrounded by wrist bones and ligaments, allows for the passage of vital structures such as tendons of flexor muscles, blood vessels, and nerves, ensuring proper blood supply, sensation, and mobility to the hand.

Flexibility: The wrist's flexibility allows for quick adjustments and adaptations in hand orientation, making it easy to move the hand in different directions during various tasks.

Shock Absorption: The wrist helps dissipate and distribute forces generated from movement or contact, providing a shock-absorbing mechanism that protects delicate structures in the hand and forearm.

By combining these functions, wrists empower human hands with exceptional dexterity, mobility, and versatility, enabling countless interactions with the environment and contributing to human beings' ability to manipulate and engage with the world around them.