I'm not so sure it is "random chance" as it is life forms adapting to their environment over billions of years. We see this in nature all the time. Creatures that have formidable defenses such as horns, tough hides, venom and the like. I don't see any of this as random chance but rather as mutations driven by the conditions in their environment that allow a species to survive and perhaps thrive. I think the gene pool of every specie is changing all the time due to outside variables and the traits that work favor that life form over others and it reproduces more readily and the ones that dont
well they die off in time. This dancing thing is something creationists do, as in this article, every time the undeniable reality of science becomes too much to bear.