The term 'Flightless Aussie Birds' refers to Emus, which are large, flightless birds native to Australia. They are the second-largest living bird by height, after the ostrich. Emus have long necks and legs, and can reach up to 2 meters in height. They are also known for their fast running speed, which can reach up to 50 km/h. Emus are omnivorous, eating a variety of plants and animals. They are an iconic species of Australia, and are featured on the Australian coat of arms.