​How do you visualize 8 billion people? These photographers zoomed in.

Last November, Earth’s population hit eight billion as scientific advances have caused child mortality to plummet and life expectancy to rise. 

At the same time, however, scientists predict this century could see the planet’s population peak—followed by a decline that will be felt in some countries more than others. Two nations in particular exemplify these opposing realities and what they might mean for the human race: Nigeria and China. 

Population change is an abstract concept to illustrate, but National Geographic tasked photographers Justin Jin and Yagazie Emezi to capture its effects in China and Nigeria, respectively, for the April issue cover story.

We spoke to Jin and Emezi about their work and what it’s like to witness this transformation firsthand.

What’s the story behind the feature on China?

For centuries, China, as the world’s most populous country, has been most strongly associated with the population boom. But soon that will shift as China’s population begins to shrink and India’s surges. 

Jin, a Hong Kong-born photographer now based in Brussels, has witnessed the shift ever since he began working as a correspondent in Beijing in the 1990s.

Back then, China was mostly worried about overpopulation. In 1978, it had instituted the so-called one-child policy aimed at slowing rapid population growth by limiting households to one child each.

That policy was officially rolled back in 2021, but Jin says the program’s legacy remains ingrained in a whole generation of Chinese people who are still keeping their families small. He argues that it’s the chief reason why the country is now facing the threat of population decline. 

It was difficult to find a family that could represent the history of birth control in China, but Jin finally found an older couple that “fit like a glove.” Before the one-child policy was enacted, the couple had three children—who in turn went on to have one child each under the government mandate. But only one of the three grandchildren decided to have a child: the older couple’s sole great-granddaughter. 

“You would imagine that this would be a continuous pyramid that gets a broader and broader base. But actually it tapered off back to one person, and now this girl is their only descendant,” Jin says. 

Other adults are choosing to not have children at all. Jin photographed one couple in Shanghai as their dogs perched next to them on a fluorescent pink flamingo float at a pet activity center. The two decided to remain childless and instead dote on their pets, like many of the city’s young residents who are DINKs–households with double income and no kids. 

Young women are also choosing to focus on their careers and personal lives instead of prioritizing marriage and children. In another image Jin captures a group of women enjoying a night out at a karaoke bar alongside a hired male escort, a vivid display of gender-role swapping in modern China.

What’s the story behind the feature on Nigeria?

Emezi is a Nigerian artist and photojournalist who has focused on African women’s health, sexuality, education, and human rights. After growing up in a smaller city in southeast Nigeria, Emezi was shocked by the sheer size of Lagos, the capital.

The country’s population has reached 224 million people, due in part to health-care advances, decreased infant mortality rate, and increased life expectancy. As a result, Emezi has seen her home country change massively over the last few decades. Hotels, bars, clubs, and more have replaced the quiet residential streets. Many areas of Nigeria have also suffered from a lack of infrastructure. 

Emezi says that population growth alone isn’t responsible for these changes—the country’s rocky transition to democracy has played a role—but it has exacerbated the problem.

She illustrated these challenges for the April issue by photographing Emmanuel and Nwakaego Ewenike, a couple that lives with their four children in a one-room apartment in the city of Ajegunle. The building has no running water or electricity, and Emmanuel, citing robberies, worries for the safety of his children in the neighborhood. The situation paints a stark reality for many Nigerians who value large families but struggle with lack of infrastructure or fair income to support their families.

Emezi says the Ewenike family portrait is her favorite from the assignment after she spent multiple days with them to gain their trust. They would have been impossible to find, though, without the help of a colleague who grew up in the Ewinikes’ neighborhood and led Emezi to the family. 

“They just happened to also be this perfect visual presentation of what we were looking for,” Emezi says.

But the image isn’t only about the downside of population growth; it also showcases joy. Emezi says the intimate moment shared with the Ewenike children playing with their father made her nostalgic for her own father, and it reminded her of the positives. 

“You witness cases of joy and all these genuine moments of love, and then the underbelly is there’s no electricity, or they have to step out to get a pail of water,” Emezi says.

She also wanted to address the diversity of experiences in Nigeria, from expectant mothers waiting to see a midwife to a group of girls at an Islamic school outside of Lagos.

What challenges did you encounter?

Both Jin and Emezi had to tackle encapsulating what population change means for these countries through clear, vivid visuals—not just charts mapping the data. That in itself was no small feat, but additional obstacles posed by government regulations and a global pandemic made the assignment seem nearly impossible.

“The hardest thing about photographing this story is indeed the abstractness of it all,” Jin says. “Population change on this scale is not something that you can really see. It’s not like suddenly there are no people on the street.” He likens China’s population shift to a warship moving a millimeter a year; it’s an imperceivable change that’s visually static.

Emezi started off by choosing larger themes, like housing, agriculture, education, and health care, before narrowing it down to specific stories. But even still, access proved to be difficult.

“Access is something that I think all storytellers just cherish. In a perfect world we will never be denied, you know?” she says. “But if you’re doing work the right way, you should be getting denied access every now and then.”

For example, it took so long to obtain permission to photograph in a hospital’s postnatal ward that Emezi ultimately suggested to her editor, Anne Farrar, that she focus instead on a more traditional health-care option in Nigeria with less bureaucracy involved: midwifery.

Jin notes that most of his images force you to think twice. For example, his opening image of babies in a postnatal center may at first glance seem to represent a baby boom, but the reality is the center offers round-the-clock care for both mothers and children so that mothers can return to their high-pressure jobs more quickly.

Jin describes the assignment as the most challenging of his career due in part to having to navigate China’s zero-COVID policy.

For example, although he managed to book a $4,000 ticket from Europe to Beijing, he was ultimately diverted to Xian, 750 miles away. Then, even after completing his mandated 10-day quarantine, Jin had to avoid rolling lockdowns in cities instead of freely traveling around China to find subjects.

Not only would cities shut down completely if even one citizen tested positive, but each province also had its own health requirements. Jin traveled to six provinces during his assignment, and each time he was nervous about whether his health status would be approved and whether there’d be another quarantine delay. 

He stayed prepared by packing a small backpack with clothes just in case an outbreak happened. Jin credits his network of friends in China for helping him travel between provinces and avoid outbreaks and queues. 

“It feels like a wave of lockdowns is constantly behind you that you’re running away from, but then at the same time, you’re also seeking out places to photograph. So you’re running away from something and you’re constantly looking for something else,” Jin says.