ANATOMYBelow are main characteristics of both species of elephants with more in-depth information on each feature. Some may be more general information while others may be more specific to each species.
Elephants are known as the largest (currently living) terrestrial mammals on the planet. The skeleton of an elephant is made up of about 326-351 bones. The vertebrae are connected by tight joints. This limits the backbone's flexibility. African elephants have 21 pairs of ribs, while Asian elephants have 19 or 20 pairs. The body temperature averages 35.9 degrees (97 degrees F), similar to a human. An elephant can raise or lower its temperature a few degrees from the average in response to extreme environmental conditions.
An elephant's skull is resilient enough to withstand the forces generated by the leverage of the tusks and head-to-head collisions when they fight other elephants. The back of the skull is flattened and spread out, creating arches that protect the brain in every direction (Something that humans lack). The skull contains air cavities (sinuses) that reduce the weight of the skull. The cranium is particularly large and provides enough room for the attachment of muscles to support the entire head. The lower jaw is solid and heavy. Since the heads are so large, the neck is relatively short to provide better support.
Elephant ears have thick bases with thin tips. The ear flaps, also known as its pinnae, contain numerous blood vessels called capillaries. Warm blood flows into the capillaries, helping to release excess body heat into the environment. This occurs when the pinnae are still, and the animal can enhance the effect by flapping them. Larger ear surfaces contain more capillaries, and more heat can be released. Elephants are capable of hearing at low frequencies and are most sensitive at 1 kHz. The first in the picture to the left is an African Elephant. As you can see, African Elephants have larger ears than that of the second picture, Asian Elephants. African Elephants are in hotter temperatures which cause them to need bigger ears to cool down quicker.
Elephant trunks are muscular, flexible extensions of their upper lip and nose of an elephant. The trunk is elongated and specialized to become the elephant's most important and versatile part. It contains up to 150,000 separate muscle fascicles, with no bone and little fat. The tip of the trunk, proboscises, enable the elephants to grasp food and other small objects. Both species use their trunks to strip vegetation from branches and to pull grasses from the ground. An elephant's trunk is a unique structure and a fundamental part of the animal's olfactory system. Elephants point their trunk in different directions to sample the air for scents. When swimming they hold their trunk out of the water much like a snorkel so they can breath. In some instances, elephants use their trunk to fend off attackers.
The tusks of an elephant are modified incisors in the upper jaw. They replace "milk teeth" when the animal reaches 6-12 months of age and grow continuously at about 17 cm (7 in) a year. A newly developed tusk has a smooth enamel cap that eventually wears off. The dentin is known as ivory and its cross-section consists of crisscrossing line patterns, known as "engine turning", which create diamond-shaped areas. As a piece of living tissue, a tusk is relatively soft; it is as hard as the mineral calcite. When removed, ivory begins to dry up and crack if not kept cool and moist. Tusks are used for digging for water, salt, and roots. They also are used for debarking or marking trees, and for moving trees and branches when clearing a path. When fighting, they are used to attack and defend, and to protect the trunk.
FUN FACT: Humans are right-handed or left-handed, so are elephants! They are right-tusked or left-tusked. It is easy to see which one an elephant is because the "master tusk," or the dominant tusk, is usually more worn down and has a rounder tip.