Elephant - Anatomy and Morphology

Anatomy and Morphology

Elephants are the largest extant terrestrial animals. Male African elephants typically stand 3.20–4.00 m (10.5–13.1 ft) tall and weigh 4,700–6,048 kg (10,000–13,330 lb), while females are typically 2.20–2.60 m (7.2–8.5 ft) tall and weigh 2,160–3,232 kg (4,800–7,130 lb). The forest species is smaller in size than the bush species. Male Asian elephants may reach 3.20 m (10.5 ft) in height and weigh up to 5,400 kg (12,000 lb), while females are 2.24 m (7.3 ft) tall and weigh 2,720 kg (6,000 lb), on average. The tail of an Asian elephant stretches to 1.2–1.5 m (3.9–4.9 ft) long. The skeleton of the elephant is made up of 326–351 bones. The vertebrae are connected by tight joints, which limit the backbone's flexibility. African elephants have 21 pairs of ribs, while Asian elephants have 19–20 pairs.

An elephant's skull is resilient enough to withstand the forces generated by the leverage of the tusks and head-to-head collisions. The back of the skull is flattened and spread out, creating arches that protect the brain in every direction. The skull contains air cavities (sinuses) that reduce the weight of the skull while maintaining overall strength. These cavities give the inside of the skull a honeycomb-like appearance. 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. Because of the size of the head, the neck is relatively short to provide better support. The eye lacks a lacrimal apparatus and relies on the harderian gland to keep it moist. The elephant eye has a durable nictitating membrane to protect the globe. The animal's field of vision is compromised by the location and limited mobility of the eyes. Elephants are considered dichromats and they can see well in dim light but not in bright light. The body temperature of an elephant averages 35.9°C (97°F), similar to a human. Like a camel, an elephant can raise or lower its temperature a few degrees from the average in response to extreme environmental conditions.