Clockwise from top left: Common squid, jellyfish Chrysaora quinquecirrha the screen, the flea beetle Aphthona flava, the annelid Eunereis longissima and the tiger.
Fabric Animals ( Eumetazoa ) ( altgr. εὖ eu good, genuine μετά (da) to ζῷον [ zoon ], Living Organism, Animal ), the multicellular animals ( Metazoa ) with real tissue. They are therefore also called True multicellular organisms. With the exception of sponges ( Porifera ) and the Placozoa include all multicellular animals to tissue animals.
Adl et al. instead, use the name of Animalia (Linnaeus, 1758) for this grouping.
The taxon of animals tissue is characterized by specialized cell types and real tissue, such as sensory cells, nerve or muscle tissue. Epithelial and other cells associated with specific cell-cell connections, the " gap junctions ". In addition, it is used in the development of the embryo by gastrulation a splitting of the cells into two cell layers ( cotyledons), the endoderm and ectoderm, the.
As basalste group of tissues animals today are no longer the cnidarians, but the Ctenophora. The systematic position of the Placozoa, formerly united with the sponges as tissue lots, is uncertain; a relationship with the cnidarians is suspected. The following cladogram is the likely relationships again:
Comb jellies ( Ctenophora )
Cnidarians ( Cnidaria )
Urmünder ( Protostomia )
New mouths ( deuterostomes )