Fossils of tropical fruits
It indicates that the land where Spitsbergen is currently was once at a tropical parallel. This is clarified by the theory of plate tectonics.
Unlike Axel Heiberg of Canada, Spitzbergen didn't move significantly away from lower to a higher altitude in the past 45 million years. However, the two territories show deposits of coal with fossil proof of warm-climate animals and vegetation.
This was not environmental change because of tectonic movements’ crosswise latitude yet an interlude of internationally warm environmental change during the Eocene period.