Category: Trivia : Analogies: 'Ancient' is to 'old' as 'recent' is to ________.?

Questions

Dogs that do not tolerate small children well are the St. Bernard, the Old English sheep dog, the Alaskan malamute, the bull terrier, and the toy ----------?

An extinct species of ---------- had a head the size of a Shetland pony's and reached a height of more than ten feet.?

---------- do not breath automatically, as humans do, and so they do not sleep as humans do. If they become unconscious, they would sink to the bottom of the sea. Without the oxygen they need to take in periodically, they would die.?

An ---------- egg can make eleven-and-a-half omelets.?

---------- swim in circles while they sleep with the eye on the outside of the circle open to keep watch for predators. After a certain amount of time, they reverse and swim in the opposite direction with the opposite eye open.?