In some key ways, a zoologist's orderly method for identifying and classifying a subject species is at odds with the multi-millennial chaos of adaptive development that led to the species as it is embodied today. If the laws of nature were as rigid as we want our classification system to be, famous taxonomic rebels such as the platypus would be forced, as mammals, to gestate and give birth to live young even if the risk to both parent and child were increased to the point of bringing about the end of the species. We are thus fortunate that the rigid biological nomenclature of science makes concessions for such an unusual marvel, one that not only scorns the basic tenets of its class, but brings new and mystifying qualities to the whole branch of its kingdom. It is hard enough to believe in the existence of a furry, duck-billed, egg-laying, venomous mammal that senses its prey through disturbances in a surrounding electromagnetic field without an unassailable checklist stating that the creature cannot by definition exist.

Select the sentence that explicitly states one of the traditional zoological characteristics of a species of mammal.





Consider each of the following choices separately and select all that apply.

Which of the following accurately describes the author's intent in writing the passage?

A. To indicate the shortcomings of using a highly structured classification system to define radically adaptive animals
B. To express admiration for the unusual abilities of the platypus
C. To make an argument in favor of changing how scientists classify animals with atypical traits