The genealogy of penguins originates near the Australian coast during the Miocene epoch, roughly 22 million years ago. Not at Antarctica as was theorized before. Then the ancestors for the two largest penguins, the emperor and king penguins separated from the Australian proto penguins to colonize Antarctica. Then about 10 million years later, other penguin families began to move away from Australia and left for other places such as Southern Africa, South America and even up north as the Galapagos Islands.While other penguin families remained on Australia, the new penguins found unexploited niches that .From there on, new adaptations such as heat tolerance, more efficient oxygen use, and maintaining osmosis due to higher salinity in seawater.
The penguin population really started to expanded only about 70,000 to 40,000 years ago, just after the end of major glaciation. Penguins do favor the colder temperatures and sea ice cover for breeding opportunites. Worringly, with the continuing threat of climate change, several penguin species such as Galapagos and the Gentoo are currently experiencing population decline. It took millions of years for them to adapt to the cold, now they are barely catching up with gradual warming of the oceans.