December 15, 2017

Invertebrates

Invertebrate

Invertebrates are animals with no internal skeleton or backbone. Invertebrates make up about 95% of all animal species on Earth. Types of invertebrates include annelids, arachnids, cnidaria, crustaceans, echinoderms, insects, mollusks, and protozoa. Exceptions include amphibians, birds, fish, … [Read more...]

Arachnids

Arachnid, Spider

Arachnids are defined as invertebrate animals that have eight legs. However, in some arachnids the front pair of legs may have adapted for feeding, defense, and sensory perception rather than walking. Almost all arachnids live on land, although some live in freshwater areas. There are over 100,000 … [Read more...]