Evolution of the cochlea about 7 mm long. Like in lepidosaurs and archosaurs, it contains a lagena, a vestibular sensory epithelium, at its tip. Only in therian mammals (marsupials and placentals) is the cochlea truly coiled 1.5 to 3.5 times. Whereas in monotremes there are many rows of both inner and outer hair cells in the organ of Corti, in therian (marsupial and placental) mammals the number of inner hair-cell rows is one, and there are generally only three rows of outer hair cells. Amphibians have unique inner ear structures. There are two sensory papillae involved in hearing, the basilar (higher frequency) and amphibian
Great Stirrup Controversy also been asserted that modern reenactment and experimental archaeology has shown that the stirrup provides very little benefit for a mounted lancer, and a cantled saddle and spurs have a greater effect. White noted the importance of the prior emergence of the saddle, but argued, "The stirrup made possible—although it did not demand—a vastly more effective mode of attack" (than a blow "delivered with the strength of shoulder and biceps"): "now the rider could lay his lance at rest, held between the upper arm and the body, and make at his foe, delivering the blow not with his muscles but