At some period on Earth, there were giant Megafauna roaming every corner of the earth. We are talking bear-sized rats, giant ground sloths twenty feet tall, wooly mammoths, and marsupial lions. Humans wiped them all out. Even in the most extreme conditions, early humans only worked 35-40 hours doing meaningful work. Nowadays, you can find people working ten hour days seven days a week in sweat shops, making barely enough to purchase food. Sapiens:A Brief History of Humankind looks at the whole history of the evolution of humans and is a total page-turner. Click the title to read more.