The drivers of imagination ? well, they say that necessity in the mother of invention, that probably covers it, imagination is a tool of creativity that helps us satisfy our needs. It's not unique to humans of course; corvids for example are well known for their ability to take or fashion tools to help them obtain food; this is imaginative use of resources.
But the brain of a corvid is tiny in relation to a human. Surely the actions induced by such a small brain will be driven more by instinct than by consciously driven imagination.
Well maybe no one matches humans for inventiveness overall and likely a corvid does not think about what it is doing in the way we do. It probably still counts as imagination at work though, imagination is not located solely in conscious mind, many of our brightest ideas come to us while we are asleep, the solution to a problem is often there for the taking when we wake up.
The brain of a corvid is tiny compared to that of a human, and that is why such insights regarding the often surprising cognitive abilities of other creatures is so intriguing. 'Brain size correlates to intelligence' is a very crude equation. To me such insights are a source of fascination, they tell of the depth of relatedness of all life. A corvid's brain might be small, but consider how tiny is the brain of a honeybee, perhaps one million neurons, around a hundred thousandth the size of ours, and yet they manage complex social interactions and communication with such tiny cerebral resources. And remember flowers are beautiful things; go look at one this afternoon and marvel at how the beauty of flowers evolved to appeal to bees, not humans, indicating that a deep ancestor of our sense of aesthetics lies there today in the tiny and primitive brain of a bee. Clues to the deep relatedness of all life and the origins of many of our own traits are all around us if we have the mind to see and wonder and try to understand.
