Chapter 25, Problem 2TYK

True or false? Some trails are considered vestigial because they existed long ago.

Summary Introduction

To review:

Correctness or Incorrectness of the statement “The traits that are considered vestigial because they came into existence long ago.”

Introduction:

The vestigial trait involves the structures that are incomplete or less developed in an organism that has reduced function or no function. These structures are often homologous to the normally functioning structures in closely related species or ancestral species.

Explanation of Solution

The vestigial traits are considered as the evidence of evolution, which justifies that certain characteristics of the species have changed with the progression of time. Vestigial traits are underdeveloped or reduced traits. These traits are considered vestigial only when they do not perform the similar function as that in the other species.

For example, the tailbone that is present in the humans has a reduced function. It is no more used for locomotion or to maintain the balance in humans. Appendix is a well-known vestigial human organ showing relation of humans with primate ancestors, part of digestion system associated with digestion of cellulose-rich plants. All the traits that existed long ago are not considered vestigial because they might perform a similar function, for which it was designed.

Conclusion

The statement is false because not all the traits that existed long ago are considered vestigial. Only those traits that have a reduced or no function, designed by nature are considered vestigial organs.