What are the main characteristics and groups of arthropods?

Here are the answers to your questions:

1. The main three characteristics shared by animals of Arthropods are:

   • They have an exoskeleton made of chitin.
   • Their bodies are segmented.
   • They possess jointed appendages.

2. The four main groups of living arthropods are:

   • Chelicerata
   • Crustacea
   • Myriapoda
   • Hexapoda