An elephant’s skull needs to be physically large in order to support the heavy tusks and powerful trunk. To minimize weight, the huge skull has a thick wall but contains large honey-comb like spaces. Male African elephants have a curved forehead. Females are more square in profile. Elephants have short necks and cannot turn their heads completely sideways. Elephant eyes are almost identical in size to those of a human. They are normally green or hazel in colour and are protected by long eyelashes. Elephants do not have tear ducts. In bright sunlight, elephants have poor eyesight. They can see best in dim light. An African elephant’s impressive ears are not just used for hearing. They help regulate the animal’s body temperature and may also be spread out wide in threat displays. Elephant ears contain a large number of blood vessels which are covered by very thin skin. When the ears are flapped, air flows over the blood vessels and the animal loses heat from them. Measuring up to 2m high and over 1m wide, 12 litres of blood can flow through each ear every minute and the animal’s body temperature can be reduced by three degrees. An elephant’s average body temperature is 35.9 degrees Celsius, just below that of a human (37 degrees). Elephants have excellent hearing and are thought to be able to communicate with other individuals several kilometres away. They can hear low-frequency sounds which are not audible to humans. The distinctive tears and nicks in elephants’ ears are used by scientists to help identify individual animals in the wild.