useless trivia: What Word Means: Propels Oneself Through Water?

Questions

The average giraffe's ---------- is two or three times that of a healthy man.?

Mother prairie dogs will nurse their young only while ---------- in the safety of the burrow. If an infant tries to suckle above ground, the mother will slap it.?

---------- have the best eyesight of any breed of dog.?

---------- have three eyelids to protect themselves from blowing sand.?

Mother-of-pearl is not always ----------. It can be pink, blue, purple, gray, or even green. Nor is it produced only by the pearl oyster. The abalone and the pearl mussel both have shells that are lined with fine-quality mother-of-pearl.?