The crowd wave at sporting events in not an entirely human thing. Prairie dogs do the "jump-yip". This keeps others involved and tells an individual how alert others are. It begins like the human wave. One or two will start doing it and at first it is ignored. Then it takes on a mind of its own and soon all are doing it.
The wave is just as noisy as the human wave with loud yips coming from everywhere. Prairie dogs use their whole body to make the sound. They raise there front legs then lower them with a "wee-oo" call in sequence. Like humans prairie dogs live in towns.
It was believed to be a warning call of the presence of predators, but prairie dogs continue the wave whether a predator is there or not. It is a social activity to test the alertness of others. If fellow animals do not respond a prairie dogs will not forage very much. On the other hand, if everyone is at it, they assume they can eat in safety. Somehow they are making a judgement about the prevailing danger.
In humans, the wave is usually done when the local team is doing well. Boredom about the state of play can trigger it as well. When the visiting team is doing well there is less motivation to do it - unless it is done in jest. It serves a social function in both species.