Terminology
The word kangaroo derives from the Guugu Yimithirr word gangurru, referring to grey kangaroos. The name was first recorded as "kangooroo or kanguru" on 4 August 1770, by Lieutenant (later Captain) James Cook on the banks of the Endeavour River at the site of modern Cooktown, when HM Bark Endeavour was beached for almost seven weeks to repair damage sustained on the Great Barrier Reef. Guugu Yimithirr is the language of the people of the area.
A common myth about the kangaroo's English name is that "kangaroo" was a Guugu Yimithirr phrase for "I don't understand you." According to this legend, Lieutenant Cook and naturalist Sir Joseph Banks were exploring the area when they happened upon the animal. They asked a nearby local what the creatures were called. The local responded "Kangaroo", meaning "I don't understand you", which Cook took to be the name of the creature. The Kangaroo myth was debunked in the 1970s by linguist John B. Haviland in his research with the Guugu Yimithirr people.
Kangaroos are often colloquially referred to as roos. Male kangaroos are called bucks, boomers, jacks, or old men; females are does, flyers, or jills, and the young ones are joeys. The collective noun for kangaroos is a mob, troop, or court. Mobs usually have ten or more kangaroos in them. Living in mobs provides protection for some of the weaker members of the group.
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