The phylum Arthropoda contains a wide diversity of animals with hard exoskeletons and jointed appendages. Many familiar species belong to the phylum Arthropoda—insects, spiders, scorpions, centipedes, and millipedes on land; crabs, crayfish, shrimp, lobsters, and barnacles in water (Fig. 3.72).
Nitrogen fixing bacteria called rhizobia
<span>When listing the components of a forest ecosystems, a scientist would list all the plants, animals and microorganisms, as well as all the non-living elements that combine to make up the entire ecology of the forest. </span>
