Assertion: porcupine's spine | /r/HasProperty | grouped in cluster
Facets:
Source sentences:
text: Old World porcupines (Hystricidae) are larger and their spines are grouped in clusters whereas New World porcupines (Erethizontidae) are smaller and have their spines attached singly.
text: The Old World species have spines that are grouped into clusters, while the New World species have spines that are attached to the skin singly.
text: Old World porcupines have spines or quills grouped in clusters, while the quills are attached separately for New World porcupines.