Assertion: elephant's back | /r/HasProperty | concave
Facets:
Source sentences:
text: African elephants also have concave backs, while Asian elephants have convex or level backs.
text: African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears, and convex or level backs.
text: They have big ears, two-fingered trunks, concave backs, flat foreheads and large tusks.