Last night we were watching Animal Homes; a woodrat (“pack rat”) was adding found objects to its impressively-large nest in the forest. The voiceover explained that these rats love anything metal and shiny. They don’t seem to make any “use” of them; they just add them into the structure of twigs and branches, seemingly at random. There was no mention of using them to attract a mate, as birds of paradise do, for example. As is common in these documentaries, the narrator ended with something to the effect of, “scientists aren’t sure what purpose this serves.”
I like thinking about the pack rat appreciating the aesthetics of the shiny objects. Like ornaments on a Christmas tree.