Insect - eating bats have sharp - edged molars for grinding hard outer shells of insects. (okcpetsmagazine.com)
Chlorella has a very hard outer shell, making it almost completely indigestible to humans, so supplemental forms undergo a special process that cracks this outer shell for enhanced digestibility. (wellnessmama.com)
Previous subspecies, like the red, yellow, and blue varieties, are joined by rock Pikmin (whose hard outer shells make them ideal for cracking particularly tough surfaces), and pink flying Pikmin, which don't enter until far later in the game, but have the delightful distinction of being able to simply fly past most major obstacles (though definitely not all). (giantbomb.com)