One thing I have learned in a long life: that all our science, measured against reality, is primitive and childlike—and yet it is the most precious thing we have.
A Dunkleosteus skull, photographed at the Royal Tyrrell Museum in Drumheller Alberta. Dunkleosteus was a placoderm fish that lived in the late Devonian, 380 to 360 million years ago. It was a hypercarnivorous apex predator, feeding on armored prey such as ammonites, arthropods, and other placoderms. Fully grown individuals had more than 700 kilograms of bite force, enough to easily shear through bone and protective tissues. Members of the largest species could grow up to 10 meters in length and weigh almost four tonnes.