Penguins have survived for over 60 million years, yet many colonies are now changing rapidly. This overview links fossils, ancient colony remains, and modern surveys to place today’s trends in a long context. Some populations are expanding, but ice-dependent species are at high risk where sea ice breaks up earlier, and food shortages can worsen where fishing overlaps. These results support protecting key breeding and feeding areas, and limiting disturbance and catches in possible warming scenarios.