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Okay let's talk about the trunk.
The trunk, or proboscis, is a fusion of the nose and upper lip, although in early fetal life, the upper lip and trunk are separated. The trunk is elongated and specialised to become the elephant's most important and versatile appendage. It contains up to 150,000 separate muscle fascicles, with no bone and little fat. These paired muscles consist of two major types: superficial (surface) and internal. The former are divided into dorsals, ventrals, and laterals while the latter are divided into transverse and radiating muscles. The muscles of the trunk connect to a bony opening in the skull. The nasal septum is composed of tiny muscle units that stretch horizontally between the nostrils. Cartilage divides the nostrils at the base. As a muscular hydrostat, the trunk moves by precisely coordinated muscle contractions. The muscles work both with and against each other. A unique proboscis nerve – formed by the maxillary and facial nerves – runs along both sides of the trunk.
Elephant trunks have multiple functions, including breathing, olfaction, touching, grasping, and sound production. The animal's sense of smell may be four times as sensitive as that of a bloodhound. The trunk's ability to make powerful twisting and coiling movements allows it to collect food, wrestle with other elephants, and lift up to 350 kg (770 lb). It can be used for delicate tasks, such as wiping an eye and checking an orifice, and is capable of cracking a peanut shell without breaking the seed. With its trunk, an elephant can reach items at heights of up to 7 m (23 ft) and dig for water under mud or sand. Individuals may show lateral preference when grasping with their trunks: some prefer to twist them to the left, others to the right. Elephants can suck up water both to drink and to spray on their bodies. An adult Asian elephant is capable of holding 8.5 L (2.2 US gal) of water in its trunk. They will also spray dust or grass on themselves. When underwater, the elephant uses its trunk as a snorkel.
The African elephant has two finger-like extensions at the tip of the trunk that allow it to grasp and bring food to its mouth. The Asian elephant has only one, and relies more on wrapping around a food item and squeezing it into its mouth. Asian elephants have more muscle coordination and can perform more complex tasks. Losing the trunk would be detrimental to an elephant's survival, although in rare cases, individuals have survived with shortened ones. One elephant has been observed to graze by kneeling on its front legs, raising on its hind legs and taking in grass with its lips. Floppy trunk syndrome is a condition of trunk paralysis in African bush elephants caused by the degradation of the peripheral nerves and muscles beginning at the tip.
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