Question

Why is it important to distinguish adaptations from exaptations?

Please provide evidence.

Answer 1

Adaptation- It is an evolutionary process where an organism gets familiar with it's environment and starts geeting well suited to the habitat. Adaptation occurs when the organism has faced a certain amount of natural forces and is now naturally selected in order to be the fittest to survive in the environment.

Exaptation- This is also called pre-adaptation. This is the phenomenon where a particular organism is initially living an environment or habitat and gradually develops a permanent character in order to survive more efficiently in the habitat.

Let us take an example to understand the difference:

Non adaptive feature -----> Natural Selection 1--------> Adaptation

Non adaptive feature-----> Adaptation by Natural selection 1-------> Preadapted by a second natural factor with new function----->Exaptation

The basic difference between adaptation and exaptation is that, a particular organism that has been already adapted to a certain habitat or environment and has the necessary characteristics to survive there currently, undergoes a separate change in a certain feature to re-establish it's survival by recruiting that particular character for a second better adaptation. This second phenomenon of recruitment of a previously adaptable feature to a new function is known as Exaptation

A very common Example: Initially dinosaurs evolved the feathers to provide them insulation against the harsh cold weather. That was adaptation against a particular change in the environment for the time being. Later, birds that evolved from dinosaurs used these feathers to fly. This new featurette added to the already adapted feathers provided a new function to the birds . Recruitment of the already adapted feathers to perform a special flight function is what is called exaptation