There are many animal images in this novel. Agatha Christie reduces them all to animals as they fight for survival. As Lombard is getting ready for dinner, he moved "like a panther, smoothly and noiselessly" and he is also described as a "beast of prey - pleasant to the eye"(pg 40)
Justice Wargrave is always described in reptile--usually tortoise - images. On page 37 it says that he "closed his eyes again, looking decidedly reptilian" and later on page 66, his eyes are again described as "hooded reptilian eyes". When asked if he had any contact with Seton before the trial "he looked round at the others,thrusting his neck forward like an angry tortoise..." (pg 55) When Justice Wargrave is resting on the terrace, he is again associated with a tortoise. "His head was poked down well into his neck." (pg 128) On page 153, he again has a "tortoise-like neck".
On page 100, Blore describes Mr. Roger's reaction when his wife faints. "He was like a cat on hot bricks." and later describes Anthony Marston as "a young bull with no nerves..." (pg 115)
When Dr. Armstrong and Lombard decide to search the island for Mr. Owen, Dr Armstrong says that they have to be careful because he will be dangerous. Lombard laughs at that and asks who's afraid of the "big bad wolf" (pg 119) It is interesting that he chose a predator for the image.
When Lombard is talking with Blore, he is retelling the story of how he got to the island. He says a man named Morris offered him a hundred guineas to come down and keep his eyes open. Then Morris "shut up like a clam" (pg 142) and Lombard feels that the guineas were just a "little bit of cheese to get me into the trap" (pg 143) like a rat.
The weather starts to change and Miss Brent says that there are "white horses on the sea" (pg 144)
Lombard is described as having a wolf-like smile.(pg 181) and later "His teeth showed in what was almost a snarl" (pg 206)
Major animal references are made at the beginning of chapter 13. Again Justice Wargrave is a "wary old tortoise". ex-Inspector Blore's walk with "that of a slow padding animal .... a look of mingled ferocity and stupidity about him....like a beast at bay ready to charge its pursuers" (pg 211) Philip Lombard's lips "curled back from his long white teeth" and Vera was "like a bird that has dashed its head against glass and has been picked up by human hands." (pg 212)
Vera gets hysterical. She tells the men "Don't you see. We're the Zoo. Last night we were hardly human anymore. We're the Zoo" pg (248). Later when they are going inside to eat, Lombard remarks that it is "Feeding time at the Zoo! The animals are very regular in their habits." (pg 251)
Vera later notices that Lombards face is "A wolf-that's what it is- a wolf's face.... those horrible teeth." (pg 262)