If population continues to increase at its current pace, the world will tip the nine billion mark by 2050. That’s up from seven billion now, a number that during most stages of human development would have been unfathomable. The big question now being asked is how to feed them while coping with dwindling natural resources, worldwide droughts, relentless famines and grinding poverty. The answers, National Geographic photographer Jim Richardson said, might be found in the past.

Richardson addressed members of the Kansas Farmers Union during their annual convention held in early December, where the convention’s theme, “Thinking Outside the Box,” reflected Richardson’s photographs taken during 20 years with National Geographic as well as his dialogues with farmers from the cornfields of Iowa to the Andes, Niger, Ethiopia, Indonesia and-literally-all points between.

“I want to find out where we are in the world of agriculture, not just geographically but in time,” Richardson said. “And I want to start not where you’d expect: beginning off the northeastern tip of Scotland in the Orkney Islands 5,000 years ago.”

There was something new on the face of the planet, he said, a neolithic revolution that had begun earlier in the Fertile Crescent that was as unstoppable as it was radically different from anything mankind had experienced: the coming of farming.

“It was a fundamental change,” he said. “They were claiming the land. They were building houses, and building tombs. They were thinking differently about the past and the afterlife. It set us on a new track.”

Since then, he said, we have remade and reshaped the planet, and with it came the massive explosion of population we have today.

Which brings us to an interesting point in human history, he said. During the next 35 years mankind will have to double food production. “Not only will there be two and a half billion more people,” he said, “we’re going to have a lot more people eating cheeseburgers than ever ate cheeseburgers before, and that means growing even more food than those two and a half billion people require. That’s the place we are in our world today.”

For most of the world, farming is still relatively primitive. When he showed photos of Ethiopians singing as they harvested oats, men behind water buffaloes wading knee-deep in rice paddies, families fixing terraces in China-terraces that had been built with simple hoes over the last several thousand years-Syrian farmers trying to plant in hardscrabble rocky soil, it illustrated not just the different agricultural practices around the world but the unique problems associated with each system and location.

Even with the current population, the world continues to struggle with agricultural problems, he said. In parts of Africa girls walk seven miles to get water, there are soil problems like salinization, and even dust storms are being seen again. “We thought they were gone but they’re back,” Richardson said. “If you’re humble and you’re honest, we’re not in control with the weather and the climate. As farmers, you have to come to grips that as much as you can control, you can’t control everything. It instills a sense of hope and a sense of dread.”

But trying to feed nine billion people isn’t hopeless, he said. Bangladesh farmers grow as much as Iowa farmers, agriculture in India is massively efficient, trees are being replanted in Ethiopia and small-scale farmers around the world are making do with what they have. In one small rocky field at 14,000 feet in the Andes, for example, a farming family produces 400 varieties of potatoes, he said.

“More importantly,” he said, “farms grow farmers as well as crops.”

Land can also be reclaimed. Richardson showed a slide of what he considered to be the ideal vision of an American farm: white clapboard house, miles of fertile cropland. The image, he said, was misleading. In the 1930s, Coon Creek Ridge was the most eroded land in America, and it was the first place the Soil Conservation Service came and started strip cropping and planting on the contour. It is now the model of fertility.

“This is something we can make happen,” he said. “But we have to recognize this: agriculture covers 39 percent of the planet’s ice-free land. We’re using almost all of it right now. And with the exception of a few places, we have no reserves of land to expand upon.”

The soil is where it began, the architect of agriculture, he said. For one story for National Geographic magazine, he decided to dig soil pits around the world to reveal the soil to non-farmers who have no idea what it looks like. For that he needed a backhoe or, in primitive cultures where mechanized machinery equals block and tackle, gravediggers. “Two six-packs of beer and you’ll have your hole in about an hour,” he said.

Slides showed virgin topsoil near Salina and farm soil in Iowa. In the latter the soil was rich and loamy and black, 18 inches deep-but in the 1870s when the farm started it was 36 inches deep, and had twice the carbon. “It starts to sound like slow-motion strip-mining,” he said. “We can’t go on that way forever.”

Within the soil were worms and insects and soil fungi, something he’d never seen before, beautiful beyond words and when photographed resembled distant nebula through the Hubble telescope. But what’s really important, he said, were the numbers of species involved.

“There are seven billion organisms in one teaspoon of healthy soil,” he said. “It’s a different world down there. You have to ask if soil is a life form rather than where life exists. It’s all interconnected.”

And then there are seeds. “These little things are carrying DNA that make new life happen,” he said. “For 8,000 years we’ve been domesticating this stuff, and this is what we should be worried about. This is what we eat.”

With domestication of seeds came industrialized farming, the lust for bigger and better equipment, mountains of grain piled in our streets. Grain elevators became icons of the plains. Farming became our culture, and that culture gave us all the credit.

Maybe it wasn’t so, Richardson said. “We talk as if we domesticated the crops, but an alternate theory goes that the wild ancestors of corn and wild wheat came to us and said, we have a deal for you: if you carry our genes around the planet and destroy our enemies and make your pastures fertile for us, we’ll feed your billions,” he said. “When you look at it that way, it’s much more of a partnership.”

Building a better partnership with the land and other farmers is the key to feeding the world’s expanding population, he said.

“It comes down to this, that contract with nature,” Richardson said. “We’ve been doing this for 8,000 years, and we’re getting pretty good at it, but we’re going to have to depend on those people who do it in so many places and so many ways. It’s the greatest challenge in human history.”