Solved by a verified expert:As you explore the Animal Kingdom, you may be overwhelmed by the incredibly diverse nature of the organisms it contains. In fact, an estimated 1 million species have been identified and the estimates of species that actually exist may exceed 7 million – most of these species are invertebrates. The number of unique life styles and structural adaptations is beyond incredible. Review the list of core concepts in the course information tab before answering the following questions.1. Explain in one paragraph why you think invertebrates outnumber vertebrates by such a large number.2. Explain the basic characteristics that are used to divide animals into the various phyla.3. Explain in detail which two core concepts are best illustrated in this section.Be sure to cite at least two credible sources (one of which must be an outside source, beyond your textbook). Friendly reminder: Wikipedia is not a credible source for this course.