I finally understand why my family tree is so small. I could only go as far back as my grandmother.
We can now trace the migrations of modern humans around our planet. It turns out that the oldest changes in our mtDNA took place in Africa 150,000 - 190,000 years ago. Then new mutations start to appear in Asia, about 60,000 – 80,000 years ago. This tells us that modern humans evolved in Africa, and that some of us migrated out of Africa into Asia after 80,000 years ago.