Immigration and Natural Law
Homo erectus emerged in east-central Africa, but its fossils are found throughout Africa, the Middle East, and into India, China, and south to Java. Homo sapiens also emerged in east-central Africa, but modern human beings are literally found in every single continent — and, yes, that does include Antarctica. Human beings have been on the move since before they even evolved into Homo sapiens.
Nothing has changed in well over 200,000 years. Human beings are the perpetually mobile ape. It’s part of our nature to always be on the move.