The Term Adaptation - Essay Example

These two definitions are summarized as the historical genesis and current utility. This presents a dilemma of incorporating distinct criteria of everyday utility and historical genesis under a single phrase. Biologists have failed to acknowledge the confusion between these two different definitions, for they tend to observe natural selection as a dominant evolutionary progression, making the historical process and the current utility seem as combined (Gould & Vrba 7). An outstanding instance of how linking these two definitions has caused misunderstanding is Darwins’ and Williams’ failure to label the infused sutures as an adaptation since they were not built by selection to function as they do in mammals (Gould & Vrba 7). Williams calls this feature an accidental effect that aids in the survival of mammals and not an adaptation. Nonetheless, these biologists failed to give the features that develop due to fitness to a current role a name (Gould & Vrba 7-9).

Since the new features that develop in organisms to aid in the survival of the descendants are not considered as an adaptation, they acquire due to capability and not natural selection and are referred to as exaptation. This generates a variance between features that develop due to natural selection and fitness to a current role. In this case, mammalian sutures are an exaptation, not an adaptation (Gould & Vrba 7-10). Exaptation offers a solution to the dilemma of preadaptation. Evolutionists and biologists have experienced trouble with the concept of preadaptation. Most of them have connected the features that develop to assist in performing a new role as preadaptation. If adaptation were developed for current use, structures functioning distinctly and subsequently could not be preadaptations. In this case, preadaptation has been associated with indeterminate theology. Theology implies a description of the role of a given feature.

Pre-adaptation has been just a classification of exaptation that is deliberated before the detail. Exaptation solves the dilemma of preadaptation. For instance, by referring to feathers, if they were initially naturally developed for thermo regulation, then they would undergo exaptation to be used for flying. However, when considering the case of the dinosaurian lineages of birds that would run, the feathers would be prospective preparations for flight. Practices, in this case, replace preadaptations to refer to the role before the actual cooptation. In this case, the trials are prospective but yet-to-be-realised exaptations. Therefore, exaptation lets precipitation replace preadaptation (Gould & Vrba 5-8).