Wygląda na to, że shellfish dzielą się na crustaceans i molluscs (mięczaki).
Takie informacje znalazłam na stronie o ptakach:
Soaring is like gliding, but a bird finds warm, rising air to carry it upward. Hawks, eagles, and vultures are all excellent soarers, as well as storks, cranes, and many other large birds.
To glide, a bird extends its strong wings completely outward and sails through the air without flapping, dropping slowly toward the ground. If you get the chance, watch a goose or duck drop down into a pond - that's a glide and they're surprisingly great at it.
Oczywiście glide też wygląda effortlessly :-)