Rusa unicolor, commonly known as the sambar deer, is a large deer species native to the Indian subcontinent and Southeast Asia. It is characterized by its robust body, long legs, and a distinctive shaggy coat that varies in color from brown to gray. Males possess antlers that can grow up to a meter long, which they shed annually. Sambar deer are primarily nocturnal and are often found in forests, grasslands, and near water sources. They are herbivorous, feeding on a variety of vegetation, including leaves, fruits, and grasses. Their social structure can vary, with some living in small groups while others are solitary.