Throughout history, an immense number of humans or humanoids have existed, each adding subtle genetic differences to the overall gene pool. This accumulation of genetic variability has shaped what it means to be human over time, illustrating the rich tapestry of human evolution and diversity.

Bill Bryson, in "A Short History of Nearly Everything," highlights how every individual, no matter how minute their influence may seem, plays a part in the grand narrative of humanity. These genetic contributions are crucial in understanding our biological heritage and the complex history that has led to our current existence.