Asian elephant
(Elephas maximus)
- Over 200 bones make up the Elephant’s skeletal system.
- It has seven neck vertebrae, but unlike most herbivores, the elephant’s vertebrae are flat disc shapes to support the weight of the tusks and trunk.
- The ribs extend down most of the spine to form a large barrel shaped rib cage.
- The limbs are made of different parts which are in a direct line with each other creating a strong support for the elephant’s large mass.
- Instead of marrow cavities the leg bones have a spongy bone helping the bones create strength and light weight.
- Elephants don’t have a collar bone but the large shoulder blades give support for muscles from the front legs
- A bulbous forehead which contain sinuses
- The brain is located in the cranial cavity; which is behind the eyes.
- Elephant has an almost vertical pelvis that is greatly expanded.
- The neck of the African elephant is almost horizontal whereas in the Asian elephant, it is held at approximately 45o.
- African elephants have up to 21 pairs, Asians up to 20.
Tusks
- The tusks of an elephant are modified second incisors in the upper jaw that grow throughout an individual’s life at a rate of several 17 cm per year. .
- They are composed of ivory, a material similar to bone that is made primarily of calcium and phosphate.
- The tusk has a pulp cavity containing nerve tissues.
- In an adult animal, about two-thirds of the tusk is visible while the remaining one-third is embedded in the socket.
- Newly developing tusks have a conical cap of smooth enamel that eventually wears off.
- Not all elephants develop visible tusks; in the Asian species, only some males have large, prominent tusks.
- Most female and some male Asian elephants have small tusks, called tushes, which seldom protrude more than an inch or two from the lip line.
- Tushes have a slightly different composition than tusks. They are small and brittle, causing them to easily break.
Ears
- Have thick bases with thin tips.
- Ear flaps contain numerous blood vessels called capillaries.
- Warm blood flows into the capillaries, helping to release excess body heat into the environment.
- Larger ear surfaces contain more capillaries, and more heat can be released.
- Of all the elephants, African bush elephants live in the hottest climates, and have the largest ear flaps.