Chapter 27, Problem 14A

Summary Introduction

To determine: The animals that have many feathery arms and tube feet.

Introduction: Echinoderms are deuterostomes which represent a significant transition in animal phylogeny. Echinoderms are aquatic mammals, and are the only species to have a deuterostome development and an endoskeleton in evolutionary history.

Explanation of Solution

Sea lilies and feather stars are the echinoderms' most ancient and plentiful species. They are distinct from other echinoderms because for most of their life they are sessile. Sea lilies have a floral body at the top of a long stem, while feather stars' long, branched limbs radiate upward from a core area. While they can remain for a long time in one location, sea lilies and feather stars are able to separate and travel elsewhere. Both aquatic lilies and feather stars collect food by spreading their tube feet and arms into the water where they snatch organic materials hanging from it.

Conclusion

Thus, it concludes that sea lilies and feather stars have many feathery arms and tube feet.