Description:

The greater tusked emu (Tuscodromius grandis) is an emu species native to Australia. These animals survived due to their adaptability to environmental conditions and the loss of their habitat. They also had adaptations to deal with the increasing amount of predators on the continent, such as hard-shelled eggs and a cursorial nature. This lineage led to one of the largest birds in Australia. This emu is extremely sexually dimorphic. The females of this species are roughly 2.9 to 3.1 meters tall, while the males are 2.0 to 2.2 meters tall. Females weigh about 60 to 92 kilograms, and males weigh 83 to 262 kilograms. They also have two tusks that are keratin outgrowths of the beak. They aren't connected to any bone and are hollow on the inside. The females have tusks that are generally longer than those of males. Females also possess a wattle, which is completely absent in males. Both males and females generally have the same feather and head coloration, however.

Distribution:

These birds are relatively widespread throughout the continent. They mainly inhabit the open grasslands, woody savanna, and hot deserts of Australia.

Diet:

These emus tend to be generalist herbivores. Their diet mainly consist of twig, seeds, grasses, fruits, berries, leaves, and other vegetation.

Reproduction:

Unlike most birds on Earth at this time, females are the largest and most colorful members of the species. Generally, females produce a loud, low, bellowing call. This call can travel for miles and communicates information to the males in the area. Once a male hears a call, he will make his way to the female. After the male arrives, the female will start to look as large as possible. Once a male chooses her, they will begin to breed. After breeding, the male will follow the female to ensure she is healthy and protected from competing males. After 2 months of staying with her, the male will create a nest made of twigs, grass, and dirt. Once the male constructs the nest, the female will lay a single egg in the nest. The father will then incubate the egg until it hatches while the mother leaves. After the egg hatches, the male will care for the chick until it is fully grown. Chicks of this bird species are precocial, meaning they are fully feathered and can move independently without their father. After hatching, the chick will immediately imprint on the father and follow him until it is fully mature.

Subspecies:

Several different subspecies live on offshore islands near the Australian coast. These subspecies tend to be smaller than the mainland subspecies, Tuscodromius grandis continentalis. Three island subspecies are currently alive: T. g. bayes, T. g. ventulus, and T. g. cavais. These subspecies inhabit the northwestern Bayes Island, the Breeze Island Chain near the southeastern coast, and the southwestern Hollow Cave Islands. All three subspecies have shrunk in size (all of them shorter than 1.5 meters) due to the island conditions. Due to the lack of predators on these islands, they are far less scared of people when compared to their mainland relatives.