The journey of life on Earth began with the first living cells, simple organisms that emerged billions of years ago. These ancient cells laid the foundation for all complex life forms, including humans. Remarkably, many traits that originated in these primordial cells are still present in our biology today. Understanding these ancient traits not only offers insights into our evolutionary history but also sheds light on the fundamental processes that govern our lives. In this article, we will explore 15 ancient traits that connect us to our distant ancestors and reveal the enduring legacy of life’s earliest forms.