Features of Proboscideans
The trunk is the defining feature of the Proboscidea; it was originally thought to be used for snorkeling underwater and is still used as such by modern day elephants. The trunk is formed from the upper lip and nose of the elephant. It is used in a variety of ways for example: to breathe, to grasp objects and to suck up water. The ‘fingers’ on the end of the trunk are very mobile. There are approximately 100,000 muscle units in an elephant’s trunk making it very mobile with many uses.

Tusks are more variable, extinct families have tusks of variable length and anatomy. This could be linked to their variable extinction but so far this claim is unfounded. Male and female African Elephants have tusks which are homologous to the incisor teeth whereas only male Asian Elephants have tusks. Baby elephants are born with ‘baby’ tusks and, much like milk teeth in humans these fall out after a year and are replaced by permanent tusks which continue to grow throughout the elephant’s life. Tusks have many functions including fighting and food finding.

Modern African Elephant ears have a large surface area and radiate heat. Ears are flapped to communicate with others with many different movements signaling different emotions. A combination of ears, feet and trunk are used to interpret long distance communications in the form of vibrations travelling through the ground from up to 10km away.

Elephants live in a social group called a herd made up of a matriarch, females and young males. All relatives help with the upbringing of young which is essential as elephants only reproduce once every 5 years. The young are precious and need to survive to adulthood to keep the species from going extinct. This reproductive strategy is known as a K strategist where very few offspring are produced but a lot of time and energy is put into their upbringing to ensure their survival. Elephants show great compassion within their herd by mourning for loved ones who die and greeting long lost friends with noisy celebrations. Elephants are good seed dispersers and 90 different plant species rely on them for seed dispersal. They also dig holes to reach underground water systems which benefit other animals in the area.

Elephants have the largest brains of land mammals but they are small in relation to their body size. Young elephants have 35% brain mass of adult elephants and their brain growth rate can be compared to that of humans. Studies show that interactions between family groups have more of an influence on elephant intelligence than actual brain size.

Above:

The trunk of an asian elephant, Elephas maximus

Reference