Bird lovers, biologists, and the curious will find these skulls, bones, and accompanying text fascinating:

Seabirds live in a complicated world. They have to cope with very different situations: flying in all types of weather, walking on land, swimming in the water, digging burrows, diving under water etc. Seabirds also have to deal with a myriad of prey and food types. No wonder they developed a wide range of foraging techniques tuned to their main source of food: from the small zooplankton to dead whales. No wonder that there exist a great variety of seabirds with a likewise great variety of adaptations.
All of these adaptations are reflected by the built of the skeleton. Although the parts are treated separately, their form and function can only be understood by looking at the whole picture: the morphology of the bird in relation to is environment, its adaptations, its foraging strategies etc.

Here is the skull of a Caspian Tern:

Via Boing Boing.