Humans and Tails :: Anatomy Persuasive Argumentative Essays

Humans and Tails When studying the anatomy of humans in biology textbooks, many authors marvel over the complexity of the human body. Attributes such as our opposable thumbs, bipedal mobility, and cognitive abilities are extolled; however, humans are at a serious disadvantage. We lack major appendages that would aid in daily living; they could greatly improve quality of life. One such appendage is a tail; understandably, some humans have grown accustomed to their current mode of living and would shy away from any change despite its advantages. For this reason, the tail that I am about to depict is prosthetic, allowing for attachment and removal when desired. A tail would give a human numerous advantages, as long as it is constructed in such a way to allow for several functions. With the proper appendage on the distal end, it could perform as a third arm, a temporary seat, or simply an aesthetic addition. All of these functions will be explained in further detail later. In order to create a tail that is as dexterous as possible, it may be useful to study the tails of several different animals and reptiles to determine what the best structure would be. Many primates have prehensile, or grasping, tails. These are comprised of articulated linkages; they cannot rotate in all directions, preventing potential flexibility. Flexor and extensor muscles act as both the driving â€Å"motor† of the tail, and attached bones serve as a support system. Another tail type is similar to an elephant’s trunk; no bone is involved in the structure. Movement is achieved through muscle contraction, and a sheath that is similar to the composition of a tendon prevents shrinkage in the overall â€Å"tail.† Sharks demonstrate a third tail type that is very unique in structure, allowing for exceptional movement. Muscles are arranged around the vertebrae in a conical formation and are attached by three-dimensional tendons. Contraction of these muscles creates a motion that is fluid, and the tail is capable of movement in all directions. In 1994, Kevin C. Zippel, a student zoologist at Cornell University made a surprising discovery. While studying in Papua New Guinea, specifically on the island of Bougainville, he found that a remarkable lizard known as the Solomon Island skink somehow evolved a very unique tail.