What are the survival advantages of ADHD?

I've been doing a lot of reading recently about evolution and the origins of the human race.  One of the really fascinating things you find is how quickly the human race can change if it finds a trait or physical characteristic that provides a survival advantage.  For example, when humans migrated out of Africa they had the dark black skin that is common among Sub-Saharan African populations today.  The dark skin color gave them protection from the hot sun of the plains of Africa and so was advantageous to them.  Fast forward several thousand years and their descendants have made it to Northern Europe as the last ice age was ending.  The human body needs vitamin D, and one of the primary sources is sunlight. We evolved near the equator where sunlight and warm temperatures were the norm.  However, in a northern climate, the days can be quite short for long stretches of time.  Thus, a light skin color that more easily absorbed the suns rays became advantageous for the humans that settled in Northern Europe and it quickly became the norm.  There are countless examples of this ongoing process that have been documented by people who study the genetics surrounding human evolution.  It got me to thinking about ADHD and why some of the traits that we find so vexing could have developed and proven advantageous to our ancestors.  

1. Restlessness, Impulsivity, and Risk-Taking: In our current society, these characteristics can become a real trouble-maker for someone with ADHD.  We can spend too much, say the wrong thing, drive our teachers or parents crazy with our inability to sit still, and get ourselves into trouble by engaging in risky behavior.  But for an individual living in a hunter-gatherer society these would be extremely useful traits.  You would be the member of the tribe willing to strike out in unfamiliar territory in search of food.  You may be the one who has the most energy and drive to find your quarry.  Because you are willing to take risks you are seen as brave and dominant.  Finally, because you have an impulsive streak, you may be more adept at trying new hunting techniques or food types.  There may be many more examples but these are a few I thought of.

2. Easily Distractible: Today, being easily distracted is another area where we can struggle.  There is so much coming at us that people with ADHD can be easily overwhelmed by outside stimuli.  But a few thousand years ago this wasn't the case.  Being easily distractible could provide a big survival advantage.  Consider that there was very little stimuli other than your fellow tribe mates.  If you are out searching for game a sudden movement or noise could be an enemy or a meal.  If you are instantly and forcefully distracted by anything outside of the norm this could lead to you eating more and being eaten less!

3. Memory issues: One of the complaints I often hear about ADHD is that someone can remember seemingly unimportant details of long ago events in great detail, but forgets to pick up their dry cleaning or mail out the bills.  In a modern society this can seem to be a quirk or disadvantage, but looking at it from a survival standpoint it makes perfect sense.  Our ancestors would have found it very useful to be able to have tremendous recall about things like where a water supply was, where a dangerous predator made their lair, or where someone once met an untimely end.  Being able to focus solely on the most critical aspects of survival; and filter out less important things allowed those individuals to stay alive longer.  Back then the only interesting thing was finding food and staying safe.  Everything else was just gravy.

While this may be just complete guesswork on my part, I can see that aspects of ADHD could have been wonderful survival tools for our long ago ancestors.  Unfortunately our modern society presents different challenges that these traits are not as well equipped to handle.  One of the most valuable things anyone with ADHD can do is to learn about the condition and gain a better understanding of it.  Thinking about it in our ancestors' lives was a fun experiment and gave me a chance to see the drawbacks of ADHD as advantages.