Humanity faces some tough challenges in the 21st century. By 2050, we’ll reach “peak population” with more than 9 billion people. That’s a quarter more mouths to feed with ever scarcer resources. We’ll be much older on average, which means that ageing nations in the Americas, Asia and Europe will become increasingly reliant on a shrinking proportion of young workers. And three out of four people will live in cities, a massive demographic shift that will force governments to create more efficient and affordable solutions for the delivery of clean water, sanitation and other essential services.

I believe that Africa can play a key role in finding solutions to each of these challenges, and the continent’s success in addressing them can put our planet on a path to more peaceful, sustainable and inclusive growth.

Over the next three decades, most of the world’s population growth will happen in Africa, which means that Africa’s farmers will need to double the region’s food production to keep up with demand. This means that Africa won’t be able to feed itself until it embraces new technologies and strategies that stimulate broad-based economic growth.

Image: UN/Economist

These include the introduction of high-yield seeds that are both drought and disease-resistant; more appropriate fertilizers; better market access for rural, low-income households; and safer ways for smallholder farmers to save between agricultural seasons. While the private sector can help introduce and distribute these innovations, investment from African governments will be essential to ensure that all farmers have equitable access.

We’ve learned that agricultural transformation isn’t just a good way to help people feed themselves. It’s a catalytic investment that drives deep and lasting GDP growth. Agricultural growth can generate four times more poverty reduction than growth in other sectors, and as the economic engine that drives Africa – employing three-quarters of the continent’s workforce and accounting for one-third of its GDP – a strong agricultural sector remains critical to stimulating savings, creating jobs, boosting intra-African trade in commodities, and helping parents invest in their children to ensure that healthy, nutritious food is available and affordable for all.

We’ve also learned that digital transformation must go hand in hand with agricultural transformation. When I ran a network of community banks in Zambia and Malawi, we found that helping farmers use their mobile phones to save money increased farm inputs and raised disposable income by nearly 20%. These savings helped increase investment in education, health and poverty reduction.

Farmers are now using digital platforms to get timely advice about local weather patterns, market prices and new-and-improved seed varieties available at the local co-op. And mobile phone services are helping agricultural extension officers collect data from farmers on local disease outbreaks, pest problems and soil conditions so that they can target interventions when and where they are needed.

Another key to achieving growth and equity in 21st-century Africa will be delivering affordable and sustainable access to clean water and sanitation. Diarrhoeal diseases caused by fecal waste remain a leading cause of death among newborn babies in sub-Saharan Africa. And chronic diarrhoeal disease is a major underlying cause of cognitive disabilities and physical stunting in children under five.

If Africa is to become a major source of global human capital by 2050 – unleashing its youth to energize an ageing world – Africa’s leaders must commit to providing low-income families in urban and peri-urban communities with sanitation services that can be purchased by families living on less than $2 per day. This will allow millions of children to achieve their full potential and contribute actively to the global economy.

But perhaps the clearest step that African governments and African social, political and religious leaders can take is to prepare for the challenges and opportunities of 2050 is to invest in the futures of women and girls. At the Bill & Melinda Gates Foundation, we are guided by the principle that all lives have equal value. But after more than two decades working to help improve the lives of the world’s poorest men, women and children, an unmistakable truth has emerged. At the core of every problem we’re trying to understand, from poverty to disease, are the undervalued lives of women and girls.

Imagine what Africa can achieve by promoting the talent and potential of every man, woman and child.

It isn’t just about making things equal for everyone – it’s about making things better and greater for all. And though we have a long way to go, when we remove barriers for women and girls, something truly transformational happens. We unleash an engine for progress that can propel massive economic growth. It’s an engine that can help more girls and boys survive and thrive. It’s an engine that can make communities and countries around the world safer, more stable and more prosperous.

That’s why leaders from across Africa and around the world have pledged to end gender inequality in all its forms. Because equal creates something greater for every man, woman and child. And they know that investing in gender equality isn’t distinct from agriculture, or digital access, or water and sanitation – it’s foundational.

I’m confident that Africa is equal to the challenges that the world will face in 2050, and I’m confident that African innovation can lead to a better world for all of us.