In nature, whether you look at forests, oceans, or human gut bacteria, a surprising pattern emerges: just a few percent of species make up most of what we see. Scientists discovered this happens because being rare is like being stuck in a sticky spot—rare species stay rare due to the mathematics of population growth, not because they’re inferior. However, these rare species aren’t useless; they act as backup species that can take over if a dominant species crashes, keeping ecosystems stable during tough times.