Which of these animals is considered a model for punctuated equilibrium?

Ammonites

Ammonites are squid like creatures that are named after the Egyptian god, Ammon. This extinct creature is an example of the punctuated equilibrium. Ammonites are the ancestors of the cephalopods. These creatures also came from the bactries. In the punctuated equilibrium, the ammonites have shown that they were able to evolve thru cladogenesis.

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".