In this 4.4-million-year-old skeleton, scientists may have found the missing step between climbing and walking.

Some animals seem to bend the rules of biology, and even physics, with skeletons that push the limits of what bones can do.

Head and neck cancers (HNCs) include malignant tumors of the lip, oral cavity, oropharynx, hypopharynx, larynx, nasopharynx, and salivary glands and are responsible for more than 450,000 deaths ...