Birds used to have teeth. Many of them, at least. From Archaeopteryx awkwardly fluttering around Jurassic lagoons to the little insect-eaters zooming through Maastrichtian forests just before the big asteroid strike, toothy birds thrived alongside their dinosaurian kin for tens of millions of years. Then they were gone. Their current absence always makes me look at the crows, jays, and robins around my neighborhood curiously - what would it be like if morning light glinted off of avian teeth?

Only beaked birds survived the end-Cretaceous catastrophe. The toothless omnivores were already well-suited to plucking morsels out of the seed bank, food kept safe from the fire and able to wait through the impact winter. Being able to make use of this food, which may have been indigestible to the more carnivorous toothed birds, made the difference. Beaked birds hung on and kicked off a new evolutionary burst that continues to this day, while the toothed birds vanished with all the non-avian dinosaurs. The best information we’ll get about toothed birds, then, comes from the fossil record itself - like a gorgeous skull found in the Early Cretaceous rocks of Spain.