The definition of Exaptation is as
follows: a trait, feature, or structure of an
organism or taxonomic group that takes on a function when none
previously existed or that differs from its original function which
had been derived by evolution. Throughout the chordate
evolution, there are several instances of this occurring. (a)
Describe three examples of chordate exaptations, (b) explain how
natural selection promoted them to occur and (c) describe the
evolutionary consequence (or outcome) in the lineages where they
evolved