Chapter 26, Problem 30A

Summary Introduction

To write:The earliest and recently developed group of arthropods

Introduction:Arthropods are grouped into classes based on common characteristics, such as body segment form, appendages and mouthparts. The naming of arthropods is still questioned by taxonomists. Arthropods have joint-appended exoskeletons that allow them to move in diverse ways.

Explanation of Solution

Trilobites are a class of extinct arthropods of the marine arachnomorph which comprise the Trilobita class. Trilobites represent one of the oldest recognized arthropod groupings.

Crustacea is made up of around 35,000 species. Many of them are marine and have two pairs of antennae, two compound eyes which are sometimes on the ends of slender horizontal stalks, and mandibles to chew.

Arachnids have a pair of appendages called pedicalps that are used to identify and retain prey. The most anterior pair of appendages of an arachnid is changed to mouthparts called chelicerae.

Due to their ability to fly and their ability to change their small size, insects live in multiple environments, allowing them to be quickly carried by wind or water. They have hard exoskeletons to prevent them from drying up in deserts and other dry areas.

Conclusion

Thus, it concludes thattrilobites are the earliest group of arthropods and insects are the recently developed group of arthropods.