23 Million Years Ago, the North Pole Was a Lush Habitat for Rhinos and Vegetation

Polar landscapes evoke a frozen land, swept by the wind and dominated by ice. However, certain archaeological discoveries reveal a very different story. There was a time when the Arctic welcomed unexpected wildlife, in a setting of temperate forests and lakes. At the heart of this forgotten past, the remains of an Arctic rhino shake up certainties, and reveal a time when the tropics flirted with the polar circle.

When the tropics ruled the Arctic

23 million years ago, at the beginning of the Miocene, the Arctic was not the frozen desert we know today. Forests of pine, birch and alder bordered lakes populated with surprisingly familiar animals. Average temperatures there were reminiscent of those in present-day southern Ontario, and summers saw dense vegetation grow under constant sunshine. It is in this temperate environment, punctuated by snowy winters and several months of polar night, that a large forgotten herbivore evolved: the hornless rhinoceros.

Paleontologists unearthed his remains on Devon Island, in the heart of the Haughton impact crater, one of the northernmost on the planet. The skeleton, 75% preserved, provided a unique window into the animal life of the ancient Arctic. Published in Nature Ecology & Evolution, the study led by paleobiologist Danielle Fraser of the Canadian Museum of Nature demonstrates that the climate of this region was mild enough to support temperate forests and diverse wildlife.

This image of a green North contradicts the vision of an eternally hostile pole. The Haughton site, now frozen in permafrost, was then a teeming ecosystem where terrestrial mammals and semi-aquatic species, such as the primitive seal, coexisted. Puijila darwini.

The Arctic rhino, witness to a vanished world

The fossil was identified as a new species:
Epiaceratherium itjilik. Comparable in size to an Indian rhinoceros, it did not have horns and fed on foliage. Its narrow snout betrays a selective grazing regime in coniferous and deciduous forests. The study specifies that the animal measured approximately one meter at the shoulder, much smaller than its contemporary African cousins, and may have had a fleece to resist the cold.

This adaptation is surprising. How was a large mammal, accustomed to temperate climates, able to survive winters lasting several months without sunlight? According to Danielle Fraser, some modern species are leading the way. Today's mammals scrape snow to access hidden plants, a behavior that the Arctic rhino may have adopted.

But the interest of the discovery goes beyond just the biology of the animal. It illustrates the ability of living things to adapt to long-term climate changes. At that time, the planet was emerging from a period of global cooling. Despite extreme cycles of light and darkness, life had organized itself, inventing strategies for survival in an unprecedented environment.

Researchers point out that this fossil is the oldest rhino ever found at such a high latitude. As Reuters points out, this northern species challenges the traditional vision of temperate zones as the only centers of biodiversity.

An impossible crossing made reality

The story of the Arctic rhino is not limited to its survival in the cold. Its existence proves that migration routes still connected Eurasia and North America long after what was believed. For a long time, paleontologists thought that the North Atlantic land bridge (once connecting Scandinavia to Greenland) had disappeared 50 million years ago. The analysis carried out by Fraser's team shows that it remained passable for at least 20 million more years.

Fossil proteins taken from dental enamel made it possible to trace the origin of this animal with great precision. The study published in Nature revealed sequences 21 to 24 million years old. These are, to date, the oldest proteins found in a mammal. Their analysis, compared to those of other species, indicates that this rhinoceros descended from lineages from Europe and the Middle East. Over time, these populations migrated to America, carried by climatic cycles and ice bridges.

This scientific feat marks a major advance for paleogenetics. It proves that biomolecules can survive in fossils much longer than previously imagined. But above all, it repositions the Arctic as a central actor in evolution. Far from being a biological impasse, this region now appears to be a crossroads of life, a place where species have learned to transform to cross the limits of possibility.

Through the silent bones of a hornless rhinoceros, science rediscovers a living, green and fertile North, which shaped the history of the world long before the ice.