There are over 8 billion human beings living on Earth. That's a LOT of people! And the world's population is still growing, which leads to a big question . are there too many of us? While humans have been on Earth, we've made huge changes to the planet. We've built cities and roads and taken over wild areas, affecting the other living things we share our world with. We've polluted our skies, land and seas and are fast using up Earth's precious natural resources. How can we lessen our impact on Earth, before it's too late?.