The emu and red kangaroo are on the Australian coat of arms, because they are unable to move backwards and symbolize the nation moving forward constantly.

The red kangaroo and emu are commonly thought to not be able to move backwards easily. They are generally thought to be on the Australian crest to symbolize a nation moving forward. The coat of arms was granted by King George V in 1912. 

It has a shield depicting the badges of the six Australian states, enclosed by an ermine border. The shield is a symbol for the federation of the states that happened in 1901. The coat of arms are generally seen with a scroll and wattle surrounding it, but they aren’t part of the Royal Warrant made for the coat of arms. 

For a long time, the words “Advance Australia” appeared on unofficial coat of arms, even before the federation of the states. It was actually included in the 1908 coat of arms and made more popular by the song “Advance Australia Fair.” In 1984, a revised version of the song became the nation’s anthem. 

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