Clasificación del Reino Animal

Abstract

Generally the animal kingdom has been classified into two large groups: vertebrates and invertebrates, however this classification does not respond to an evolutionary criterion because not all invertebrates have a recent common predecessor.

At present, to classify the animals are used several criteria that try to deduce the evolutionary relations between the different groups. These criteria, which determine the degree of morphological complexity are:

Number of tissue layers in which cells are organized The symmetry of the body and the arrangement of its parts The presence or absence of body cavities (coelom) and the way they are formed Developmental pattern from the fertilized ovum to the adult animal

Below is the classification and the most salient divisions of the animal kingdom and indicates the fundamental aspects that are used to group the different phylum (Aguirre & Ramirez, 2013).