[MakeShift was a column and competition, by MacGyver creator Lee Zlotoff, that ran in Make: magazine for its first five years. This challenge appeared in Make: Volume 18, 2009. Read past installments of MakeShift here.]
You and a friend, both experienced campers, are out for a wilderness weekend in one of your favorite desert areas when, around sunset, you see a large, densely concentrated, directional swarm of bats sweeping low across the landscape. Intrigued by the sighting, you hike back along their flight path until you come upon the entrance to a cave from which they emanate — a cave that, as far as you know, is unknown. And the lack of any signs of human activity around the entrance seems to confirm that.
Not wanting to pass up this once-in-a-lifetime opportunity for some genuine adventure, you convince your friend to at least go in a little way to explore the cave. Gearing up with packs and flashlights, you tie a guide rope to a bush near the entrance and slip through the narrow opening to have a look inside. The cave quickly widens, and once you get past the odor of the bats, you’re both astonished by the undisturbed beauty of the structure. You venture deeper into this pristine geo-world until the rope runs out, but neither of you is keen to stop now. So you agree to make directional markers along the way in order to explore farther – marks cut into the cave floor or walls, piles of stones, bits of fabric; whatever they are, assume that they stick.
Taking many turns through naturally formed tunnels and chambers, you’re both so involved that you finally realize that neither of you has been trail-marking for some time. The flashlights make everything seem bright, but when they’re off it is pitch black. A little backtracking doesn’t find your last markers, and you realize you’re most definitely lost. You hear the chittering of a few remaining bats and the dripping of water, but other than that and your breathing, the cave is deathly silent. So, aside from resisting the urge to panic, what do you do now?
What You Have
Two sturdy, aluminum-frame overnight backpacks, two canteens of water, some protein bars and other durable foods, two flashlights with extra batteries, a Swiss Army knife or Leatherman tool, a strong, flexible 3-foot wire saw with split-ring finger-handles on both ends, some waterproof matches, a compass, a cellphone (no, you don’t get a signal down here), and a GPS locator (also no signal). Besides your hiking boots, you each have waterproof nylon rain gear and a nice warm jacket. So, can you find your way out, or have you truly reached the end of your rope?
Analysis and Commentary
We were pleased, though not surprised, to see that most of you jumped to the simplest and most certain way of extricating yourself from this tricky and potentially dangerous situation, namely looking, if not listening to, the bats themselves.
Since following the bats got you into this situation, following them once again can get you out. Bats always fly to and from their caves at the same general times each day, leaving en masse near sunset, and returning at dawn. And they always use the same convenient opening to the cave for their comings and goings. You and your friend followed the bats as they returned home at dawn and entered the bat cave through the flight-entrance in the morning when the bats were home for the day. Once underground in a bat cave, even if you become lost you can always find the surface opening by just following the bats as they navigate toward the surface, since they fly as a group and always use the same exit to hunt for food at night.
Of course, being the exceedingly clever folk you are, many of you tried to come up with more inventive ways of working your way out, involving using compasses, GPS, flags, or smoke from small fires to follow the internal air currents.
However, unlike mines, which generally have only a very few, often just one opening to the surface, natural caves can have many exits to the surface, most of which could not be navigated by a human even though they allow airflow. So lighting a fire to follow escaping smoke and airflow patterns would not be a good choice, since not only might the smoke pool and contaminate the breathable air, but with many possible entrances, following an air flow pattern could get you in even deeper trouble. Using your GPS or compass would not help much either since you didn’t think of using them until you discovered you were lost. And taking a GPS reading or getting a compass heading from a point where you are totally lost is of little value.
Several of you also suggested splitting up with your friend to explore in different directions. And, while you could perhaps cover more territory in search of the exit that way, we didn’t think that was really advisable. Two heads are better than one. Two people can work to keep each other calm and focused, and if you both go off exploring in different directions, at least one of you will be headed the wrong way. And should one of you stumble into worse trouble, your problems could be considerably compounded.
Sometimes, the simple and most obvious answer is the best way to go. By conserving your flashlight batteries for when you will need them to first locate, and then to follow the bats as they leave the cave is, to our thinking, the most promising and reliable course of action. And, with hardly any luck, you and your friend should, within 24 hours, or 36 at the most, be able to find your way back to the surface.
So, fear not the bats or getting lost should you find yourself exploring one of their here-to-fore undiscovered caves, because now you are well-armed with the knowledge you need to return to the world of the living.
We’re sure Arnie Saknussen would be impressed by you all!
The winners of the MakeShift Volume 18 Challenge are: