The prions are small and typically eat just zooplankton; however as a member of the Procellariiformes, they share certain identifying features.

They are then members of the Procellariiformes order, and they share certain identifying features.

They all share certain identifying features.

The fulmars are in turn a member of the order Procellariiformes, and they all share certain identifying features.

These birds share certain identifying features.

As a member of the Procellariiformes, they share certain identifying features.