tree shrew vs placental mammal

tree shrew and placental mammal both are nouns.

Word	Noun	Adjective	Verb	Adverb
tree shrew	Yes	No	No	No
placental mammal	Yes	No	No	No

As nouns, placental mammal is a hypernym of tree shrew; that is, placental mammal is a word with a broader meaning than tree shrew:

tree shrew: insectivorous arboreal mammal of southeast Asia that resembles a squirrel with large eyes and long sharp snout
placental mammal: mammals having a placenta; all mammals except monotremes and marsupials

Other hypernyms of tree shrew include eutherian, eutherian mammal, placental.

tree shrew (noun)	placental mammal (noun)
insectivorous arboreal mammal of southeast Asia that resembles a squirrel with large eyes and long sharp snout	mammals having a placenta; all mammals except monotremes and marsupials