Grass conquers the World

Giant mammals evolve

At the beginning of the Oligocene, about 36 million years ago, the Antarctic continent broke away from South America and Australia, drifting south. This allowed today's polar ocean current to form around Antarctica, having far-reaching consequences for the climate of our planet.

The global temperature dropped by about 5 °C, and in some parts of Antarctica, large glaciers formed for the first time since the Permian Age. A similar, albeit less pronounced effect occurred in the northern hemisphere due to the opening of the sea route between Scandinavia and Greenland.

The growth of the glaciers in turn led to a lowering of the sea level, and thus some new land connections were formed. The Ebro Basin, for example, southwest of the Pyrenees, rose out of the sea and formed a land bridge between the Iberian Peninsula and the rest of Europe. The African continent, on the other hand, remained largely isolated. This was only to change in the Miocene following the Oligocene.

The dry and cool climate of the Oligocene produced huge mammals. The direct ancestors of the rhinoceros, horses, pigs, camels, and rabbits developed during this time and reached astonishing sizes.

And things were also happening in the plant world: the first grasslands were forming in Asia. Grass was to become one of the most successful plant species of all time and covers a fifth of the earth's surface today.