Scientists recently suggested that Earth’s sixth mass extinction has begun. As terrifying as that sounds, surely humans are too smart and important to get wiped out, right? Paleontologists have long tried to shed light on this question by looking for general rules that might predict the survival of a species. While this is not a straightforward exercise, research so far indicates that the odds are not in our favor.

Life on Earth can be traced back to a single unicellular species, perhaps some 3.5 billion years ago. Since then, diversity and maximum complexity has increased and millions of species have evolved. But how did we go from one species to millions of species? Let’s do a simple thought experiment. Lineages can split in two so that one species yields two, two yield four, four yield eight, and so forth. FULL REPORT