Assertion: butterfly's skeleton | /r/HasProperty | a.k.a. endoskeleton
Facets:
Source sentences:
text: Butterflies belong to the Phylum Arthropoda (which includes other animals like crustaceans, spiders, millipedes, as well as all other insects), and all Arthropods must molt their external skeleton (a.k.a. exoskeleton) because it does not grow continuously like the internal skeleton (a.k.a. endoskeleton) of vertebrates.