Procrastination seems at first to be a unique human attribute, but I think it is universal to all things with at least half a brain. It is in other words something more ancient, a byproduct of evolution. Thankfully, there is no need to postulate a dawdling gene, as an evolutionary psychologist would be wont to do. Actually, I propose that it is a spandrel, an unexpected and unintended consequence of how our brains are made up to make up their minds, in this case at the last minute.
Consider this. If I prepare my income taxes, buy Christmas presents, and take out my garbage, all with days to spare, all the good things entailed by this behavior would be certain, and may arrive earlier (like a tax refund) to boot. However, doing these tasks at the last minute makes the arrival of these good things a bit more uncertain, as when we finally make it under the wire, we are usually pleasantly surprised. Which is exactly the point.
Ironically, certainty is a matter of dread, or at least for dreadful boredom for almost all living things that need to walk, scurry, or scuttle about. The fact is, we are wired to be sensitive to positive and uncertain things. Called a seeking or foraging response, it simply entails that when we encounter or anticipate positive and surprising things, the brain will release neurochemicals (dopamine,mainly) that will perk up and center our attention, and provide an affective valence (i.e. it feels good) that gives extra value to what we are doing or thinking about doing. Without it, we would be bored, indifferent, and will end up shuffling about endlessly without purpose, or in other words, dawdling. Procrastination is thus our unconscious way of adding a little uncertainty to the daily and certain things which make up the drudgery of daily existence.
So the next time you are scrambling to catch a plane, running an errand for the wife, or just getting to work on time, understand that procrastination is quite literally the neural equivalent of the spice of life.
I'd write a bit more, but I gotta run.