How much life is on Earth? Scientists still don’t really know, though one study suggests there are around 8.7 million species (not counting tens of millions of bacteria). The number of individual organisms is even more gigantic and impossible to comprehend. National Geographic photographer David Liittschwager took a different approach and trimmed the question down: How much life is in a single cubic foot of nature?
"It’s kind of a personal-size biological sample," Liittschwager says. "It fits in your lap, you can put your arms around it. It’s a manageable-size piece of the world."
The photographer took a bright metal cube, measuring 12" x 12" x 12", to five different places around the world: A coral reef, a river, the canopy in a cloud forest, shrubland, and a patch of fallen leaves in the woods. In each location, he set the cube down, backed off, and watched animals travel in and out. Later, he carefully photographed everything and worked with biologists to document what he had seen.
Each cube teemed with life, even a sample taken in the middle of New York's Central Park. "Even if we stay away from the little stuff like mites, there are 1,000 creatures in one cubic foot of Central Park," he says. "That’s the same number of creatures that we found in a tropical coral-reef crest. Although the coral reef was diverse and pretty, a little piece of Central Park was alive to the same extent."
There was so much to photograph that even after weeks in each location, he couldn't cover it all. "I never finished any of them because there was always more to see," he says. "I thought it was this manageable, reasonable idea, but I found out that the world was far more interesting than I ever thought."
That gives him hope. "The world’s damaged and 7.5 billion people are going to make a lot of serious changes," Liittschwager says. "But there's still a lot of stuff we get to take with us into the future if we choose to do that. The world's not used up yet, and there's no reason to sit on our hands and say that it's over."
The photo series was published in 2010 in a book called A World in One Cubic Foot. Now, the photographer is working on a tutorial video that he'll be sharing with middle- and high-school students so they can repeat the same experiment in their own backyards and share the results.
Liittschwager sees the world differently. "I look with great affection at little corners of the world—even in urban environments, places where a little dirt builds up and weeds start to grow," he says. "I notice life everywhere now."