1 OstrichOstrich is the largest and heaviest living bird on Earth. An adult Ostrich stand up to a height of 6 feet and weighs up to 150 kilograms. A male Ostrich is called a rooster and a female Ostrich is called a hen. An female Ostrich can lay 40 -100 eggs per year, averaging about 60 eggs per year. With long, muscular legs, ostriches can run as fast as 70 km/h (43 mph) and hold steady speeds of 50 km/h (31 mph).
2 Southern cassowarySouthern Cassowary, also known as double-wattled cassowary, is the second largest bird in the world. Known for its aggressive behavior, it is primarily found in the tropical rain-forests of Indonesia, New Guinea, and islands of northern Australia. The bird measures about 13 to 16.9 cm (5.1 to 6.7 in) in height, weighing an average of 75 to 80kg. Their diet consists mainly of fruits, insects, and vertebrates.