There are about 40,000 to 50,000 Asian elephants in the world. Two thirds live in the wild, the rest in captivity. The wild population is endangered, facing habitat loss as forested areas are shrinking. This wild male is crossing a road in Bardia National Park in Nepal.

A female elephant gives birth to one calf at a time, with intervals of a few years. Twins are very rare. These twins, called Ram Gaj and Laxman Gaj, were born at the Elephant Breeding Centre of Chitwan, Nepal, in 2009.

This one-year-old is the size of a pony, but still a baby. An elephant has a lifespan similar to that of humans. They reach sexual maturity in their teens and are almost fully grown at the age of 20. In the wild, they can reach the age of 60 or 70. In captivity, the lifespan is often shorter.

The trunk is the most sensitive part of an elephant’s body. Placing the tip of one’s trunk into another elephant’s mouth is a friendly signal, indicating trust in the other individual.

A grown-up elephant eats from 150 to 300 kilograms (330 to 660 pounds) of plant material per day. The elephant also needs quite a lot to drink. If a large part of the food is dried, such as hay, the elephant will need 100 to 200 litres (22 to 44 gallons) of water daily.

Once a male elephant has matured, he starts experiencing phases called the musth. These are periods during which his level of testosterone is dramatically higher than normally, and he becomes more competetive and aggressive towards other males. One of the outward signs of musth is a dark fluid secreted from his temporal glands, as can be seen in this tuskless male.

The Asian elephant is the closest living relative of the extinct woolly mammoth. Tufts of hair can still be seen on today's elephants, especially often on top of the head of young ones.

Many aspects of friendly communication are expressed by various touches by the trunk. A loud rumbling noise, so low-pitched that it usually is below the human hearing range, is another frequently used social signal within a group.

In the wild, female elephants live in family groups consisting of close relatives and their offspring. This family group has been photographed in semi-natural conditions at Elephant Nature Park, a sanctuary for mistreated working elephants in Thailand.

The appearance of Asian elephants varies throughout their range. For example in Thailand, where this photo is taken, elephants are smaller than in northern India. The elephant on the right has unusually little pigment. This is the colour that sometimes is called a "white" elephant.