A shared shape rule, the power cascade, governs most bird beak growth. It links modern birds with extinct dinosaurs.

Otherwise, their bodies are mostly muted gray or brown ... behind the bird as it soars high. While both male and female adults look the same, the young have short and yellow beaks.

The long tail is rounded at the tip, also the relatively short wings and flat-topped head are good field marks. Eye is close to the beak ... Juvenile: brown above, with rufous edges and white ...

medium-sized bird with a long, thick beak. Males have cinnamon-brown feathers covering most of their bodies, but their wings and tails are a vibrant teal hue; females have pale white breast feathers.