How do you know if there's a dinosaur in your fridge? Footprints in the butter, of course. How do we know about dinos in the ground? Fossil pioneer Nicolas Steno, celebrated today by Google.
Today's Google home page depicts a geological Google logo stratified and filled with fossils, to celebrate what would have been the 374th birthday of the man who developed the theory that fossils are the remains of dinosaurs.
Steno was born Niels Stensen in Copenhagen on this day in 1638. Surviving the plague, which killed 240 of his schoolmates, he grew up to be a scientist who insisted on trusting his own observations even if they went against established doctrine. Excellent, we love a maverick.
As a geologist he spotted that sharks' teeth were similar to strange stony objects found in rock formations. Previously scholars thought these 'tongue stones' grew in rocks or fell from the sky. This led him to define three defining principles of stratigraphy, the branch of geology that studies rock layers: superimposition, which suggests newer layers form on top of older layers; horizontality, which suggests they form in horizontal layers; and lateral continuity, which suggests rock layers continue over the surface of the earth.
As if that wasn't enough, he also came up with Steno's Law, a fundamental principle of studying crystals. No doubt he would also have invented the joke, "What do you call a three-eyed dinosaur?", given half a chance.
Interestingly, this man of science was also deeply religious. Born a Lutheran, he converted to Catholicism and became a priest, then a bishop. In his later years, he dressed shabbily, refused to yield to snow and rain, and ate only bread and beer four days a week. Steno died on 25 November 1686, and was beatified by the Catholic Church in 1988.