Twenty-five years ago, geologist Peter Hochuli was on an expedition in Norway when he made a discovery in a sediment core - a long round sample of soil or rock - that puzzled him.  

“And there I found first these amazing pollen grains which looked to me like the ones that I knew from the Cretaceous,” he said.

That is the relatively warm geological period 140 million years ago, when dinosaurs dominated the landscape, and scientists believe new groups of mammals and birds, as well as flowering plants, appeared. The problem was that he had dated the core to the Triassic, or 100 million years earlier in earth’s history.  

“But for many of my colleagues, it didn’t fit the picture that these pollen are occurring in the middle Triassic. So I thought they were contaminants, and I suspected that they came from the lab. In the lab they also prepared Cretaceous sediments. So I also thought they made kind of a mess,” said Hochuli.

But he does not think so anymore. Now a paleo-botanist at the University of Zurich, Hochuli has focused his research on finding the origin of flowering plants, which evolved from extinct plants related to today’s conifers, seed ferns and pollen.