The emu, Dromaius novaehollandiae is a large, flightless bird native to Australia. It is the largest bird on the continent, and the second largest in the world, after the ostrich. Together with the Australian cassowary, these giant birds make up the avian family Casuarriidae.
The largest specimens of emus can reach up to six and a half feet in height (2 m) and usually weigh about 66-121 lbs (30-55 kg.) They are exceptionally fast runners, able to reach speeds exceeding 30 miles per hour (50 kmh) and maintain that speed for some time. Their stride may be as much as nine ft (2.7) in length. They have a long neck and large three-toed feet, and are strong swimmers.
Emus have an excellent biological adaptation for dealing with the heat of Australia. The long, shaggy coat of the birds absorbs solar radiation, effectively insulating the bird from the heat. This allows them to remain active during the day, an important factor of survival in the extreme heat of the outback. During hot weather, the bird can also pant, using its lungs as a cooling mechanism for its body.
During mating season, emus form temporary mating pairs, remaining together for five or six months. In May and June, the female lays several eggs every few days that are roughly ten times as large as chicken eggs. The male incubates the eggs exclusively, while a female emu may mate with other males after her initial laying is complete. Males do not eat or drink during incubation, and do not leave the nest. After two months, hatching occurs and the chicks are cared for by the adult male birds.
Hatchlings mature in approximately one year, and often stay with their fathers for 18 months. The lifespan of wild emus is 10-20 years, although captive specimens have been known to live nearly twice as long. Hatchlings have provided researches with the only evidence of identical twins among birds, although studies suggest this are exceptionally rare.
Aboriginal cultures have long hunted the emu for its coat, meat and supposed medicinal properties. In the late 20th century, commercial raising of the birds for meat and leather began in Australia, North America and China. The popularity of the meat is believed to be due to its low fat content and gamey flavor. Emu burgers are now popular items at some restaurants.
In Aboriginal mythology, the sun is said to have been created by an emu egg being thrown into the sky. Throughout Australia, about 600 towns, lakes and landmarks have been named for the birds, and an Australian company even markets a line of Emu beers. It is a popular symbol of Australian culture and a beloved mascot of the country.
A Tasmanian subspecies of the bird is believed to have become extinct in the mid 19th century, but Australian populations of the bird are relatively stable. The emu’s success in the wild is attributed to its large reproductive rate and well-adapted behaviors. Still, the birds can be threatened by common Australian wildfires and human encroachment on natural ranges. For the moment, the emu maintains a thriving population.