In summary, our results indicate that, so far, SARS-CoV-2 has evolved through a nondeterministic, noisy process and that random genetic drift has played a dominant role in disseminating unique mutations throughout the world. Yet, it is important to note that founder effects do not exclude that the D614G can confer distinguishing properties in terms of protein stability, infectivity, or transmissibility. SARS-CoV-2 was only recently identified in the human population—a short time frame relative to adaptive processes that can take years to occur. Although we cannot predict whether adaptive selection will be seen in SARS-CoV-2 in the future, the key finding is that SARS-CoV-2 viruses that are currently circulating constitute a homogeneous viral population. Viral diversity has challenged vaccine development efforts for other viruses such as HIV-1, influenza, or Dengue, but these viruses each constitute a more diverse population than SARS-CoV-2 viruses (SI Appendix, Fig. S12). We can therefore be cautiously optimistic that viral diversity should not be an obstacle for the development of a broadly protective SARS-CoV-2 vaccine, and that vaccines in current development should elicit responses that are reactive against currently circulating variants of SARS-CoV-2.