When you think of a hippo, you most likely think of African watering holes, or else the big mammal mostly-submerged, lazily drifting down an African river.

Besides the hippos and the water, those images have one thing in common: the sub-Saharan African location.

And this makes sense, since we all know that that is where hippos live.

The common hippopotamus (Hippopotamus amphibius) did once occupy very different parts of the Earth, and the hippo was actually once a crucial part of the European ecosystem.

Until recently, the consensus was that European hippos were a thing of the distant past, with the creature allegedly becoming extinct on the continuent toward the end of the last interglacial period, around 115,000 years ago.

But in a fascinating new study from a team led by researchers at the University of Potsdam, and published in the journal Current Biology, science’s understanding of hippos in Europe has been significantly challenged.

By conducting radiocarbon dating and paleogenomic analyses, the researchers were able to prove that not only did the species not, in fact, become extinct in Europe 115,000 years ago, they were actually still present in Europe during the middle Weichselian glaciation (some 55,000+ years later than thought), as Dr Patrick Arnold explained in a statement:

“The results demonstrate that hippos did not vanish from middle Europe at the end of the last interglacial, as previously assumed. Therefore, we should re-analyze other continental European hippo fossils traditionally attributed to the last interglacial period.”

Though they survived in the region much longer than expected, the researchers’ results showed that their genetic diversity was low. This suggests that the hippos weren’t particularly numerous.

But genetically, the European hippos were very similar to the hippos we still see in Africa today, showing how little things have changed for the massive mammals in this huge timespan.

The new data suggests that hippos were present in Europe throughout the cold spells in which mammoths adapted to become woolly – so the fact that the hippos (traditionally heat-loving creatures) stayed the same, is a fascinating avenue for future research, as Reiss-Engelhorn-Museen Mannheim’s Prof. Dr. Wilfried Rosendahl continued:

“The current study provides important new insights which impressively prove that ice age was not the same everywhere, but local peculiarities taken together form a complex overall picture – similar to a puzzle. It would now be interesting and important to further examine other heat-loving animal species, attributed so far to the last interglacial.”

All this goes to show how much we still have let to learn about the planet we call home, and the species we coexist with.

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