Sulcavis geeorum is an enantiornithine bird from the Early Cretaceous (121-125 million years ago) of Liaoning Province, China. Enantiornithine birds are an early group of birds, and the most numerous birds from the Mesozoic (the time of the dinosaurs). Sulcavisis the first discovery of a bird with ornamented tooth enamel. The dinosaurs -- from which birds evolved -- are mostly characterized by carnivorous teeth with special features for eating meat. The enantiornithines are unique among birds in showing minimal tooth reduction and a diversity of dental patterns. This new enantiornithine has robust teeth with grooves on the inside surface, which likely strengthened the teeth against harder food items.
Beak shape variation in Darwin's finches is a classic example of evolutionary adaptation, with beaks that vary widely in proportions and shape, reflecting a diversity of ecologies. While living birds have a beak to manipulate their food, their fossil bird ancestors had teeth. Now a new fossil discovery shows some fossil birds evolved teeth adapted for specialized diets. A study of the teeth of a new species of early bird, Sulcavis geeorum, published in the latest issue of the Journal of Vertebrate Paleontology, suggests this fossil bird had a durophagous diet, meaning the bird's teeth were capable of eating prey with hard exoskeletons like insects or crabs. The researchers believe the teeth of the new specimen greatly increase the known diversity of tooth shape in early birds, and hints at previously unrecognized ecological diversity.