Evolution of the cochlea Evolution of the cochlea Cochlea is Latin for “snail, shell or screw” and originates from the Greek word κοχλίας "kohlias". The modern definition, the auditory portion of the inner ear, originated in the late 17th century. Within the mammalian cochlea exists the organ of Corti, which contains hair cells that are responsible for translating the vibrations it receives from surrounding fluid-filled ducts into electrical impulses that are sent to the brain to process sound. This spiral-shaped cochlea is estimated to have originated during the early Cretaceous Period, around 120 million years ago. Further, the auditory innervation of the spiral-shaped cochlea
Stirrup word "stirrup" stems from Old English "stirap, stigrap", Middle English "stirop, styrope", i.e. a mounting or climbing-rope. From Old English "stīgan" "to ascend". The stirrup, which gives greater stability to a rider, has been described as one of the most significant inventions in the history of warfare, prior to gunpowder. As a tool allowing expanded use of horses in warfare, the stirrup is often called the third revolutionary step in equipment, after the chariot and the saddle. The basic tactics of mounted warfare were significantly altered by the stirrup. A rider supported by stirrups was less likely to fall off