Brazil has a diverse landscape that includes narrow coastal plains, highlands, and lowland river valleys. It is home to the second longest river in the world, the Amazon River. Brazil has a large and diverse population of over 176 million people that is made up of European, African, Native American, Asian, and mixed ancestries. While agriculture, mining, and logging make up much of its economic activity today, rubber extraction drove its economy in the 1800s. Brazil was colonized by Portugal in the 1500s and used Native Americans as slaves until widespread disease and African slaves replaced them, influencing Brazilian culture. It is now a democratic republic with a strong central government where voting is mandatory for citizens aged 18-70.