Chapter 24, Problem 24A

Summary Introduction

To write:

How segmentation and exoskeletons gave some animals an adaptive advantage over those that were not segmented and did not have exoskeletons.

Introduction:

Segmentation is a main function in the evolution of coelomate animals. Just as a series is comprised of series of links, segmented animals can be “put together” from a succession of similar parts.

Explanation of Solution

The segmentation, such as that visible in scorpions, has two advantages. First, segmented animals can survive damage to one segment due to the fact that different segments might be capable to carry out the damaged section’s function. Second, movement is more effective due to the fact that segments can move independently. Therefore, the scorpion has more flexibility and may move in ways which are very complex.

Conclusion

Segments permit the scorpion to arch its tail over its back to sting prey. Thus, segmentation and exoskeletons gave a few animals an adaptive benefit over that have been now no longer segmented and now no longer have exoskeletons.