I was just in Australia and went to an Emu park. On our way to the Emus the guide showed off a Bowerbird nest. The birds go around picking up shiny things like

I was just in Australia and went to an Emu park. On our way to the Emus the guide showed off a Bowerbird nest. The birds go around picking up shiny things like bits of glass or metal to decorate their nest to attract females. Rival birds will go stealing the best bits from other birds' nests causing fights. Heck, even if a human just rearranges some of their bits of flair in the pile, they'll notice and put it back in its place. https://www.youtube.com/watch?v=5vpeZWNYoWU https://www.youtube.com/watch?v=5vpeZWNYoWU It's not even a human thing, this is a fundamental thing that animals like to do. Try to get the best, shiniest stuff to show off how much better you are than the other mate. We've just managed to use our intelligence to manipulate each other into influencing what is seen as more or less shiny.