The original word kangaroo originated from the Native Australian language known as Guugu Yimithirr. The animal was referred to as the gangurru. Captain James Cook and his crew set foot on the island, discovering the odd animal in all its splendor, which they then renamed to kangaroo. Adult males are known as boomers, adult females as flyers, and baby kangaroos are joeys. Today, the kangaroo is almost synonymous with all of Australia, as they are such a common beast wandering the wild. Here are ten kangaroo facts that will make you hop with joy.