Eumetazoa

(redirected from Eumetazoan)

Eumetazoa

(yo͞o'mĕt'əzō`ə), subkingdom of the animal kingdom comprising all animals except the spongessponge,
common name for members of the aquatic animal phylum Porifera, and for the dried, processed skeletons of certain species used to hold water. Over 4,500 living species are known; they are found throughout the world, especially in shallow temperate waters.
..... Click the link for more information.
 and the wormlike mezozoans (see MezozoaMezozoa
, name of an animal subkingdom and also of the subkingdom's only phylum. The mezozoans are simple parasitic marine wormlike animals of only 20 to 30 cells, which are differentiated only into reproductive cells and ciliated cells.
..... Click the link for more information.
).
The Columbia Electronic Encyclopedia™ Copyright © 2013, Columbia University Press. Licensed from Columbia University Press. All rights reserved. www.cc.columbia.edu/cu/cup/

Eumetazoa

[yü‚med·ə′zō·ə]
(zoology)
A section of the animal kingdom that includes the phyla above the Porifera; contains those animals which have tissues or show some tissue formation and organ systems.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.
References in periodicals archive ?
Knoll, "Eumetazoan Fossils in Terminal Proterozoic Phosphorites?," PNAS 97, no.
(2000) hypothesized that these worms precipitate their hard parts by a method, hitherto unknown in eumetazoan animals.
Sea anemone genome reveals ancestral eumetazoan gene repertoire and genomic organization.
In spite of the fact, however, that Hydra belongs to the phylogenetically oldest eumetazoan lineage, this or-ganism certainly is not a "living fossil"; its genome contains a rather unique combination of ancestral, novel (see Khalturin et al., 2009), and "borrowed" (e.g., via horizontal gene transfer) genes, similar to the genomes of other animals.
The newly advanced theory for the origin of the eumetazoans (Nielsen, 2008b) proposes that the ancestral eumetazoan which Haeckel (1874) called gastraea did not evolve directly from a blastaea, but from sexually mature larvae of a homoscleromorph-like sponge with a pelago-benthic life cycle.
Many genes that were thought to be restricted to vertebrates or deuterostomes were likely present early in eumetazoan phylogeny.
There is no evidence of other ANTP class homeobox genes--Hox, ParaHox and EHG-box--in the sponge genome, thus we also hypothesize that the eumetazoan ProtoHox gene originated from within the ancestral NK cluster after the divergence of sponge and eumetazoan lineages.
2007, Sea anemone genome reveals ancestral eumetazoan gene repertoire and genomic organization.Science 317:86-94.
This is a reasonable starting point because, despite the morphological diversity and nonhomology of eyes, it is well documented that the majority of eumetazoans use an opsin-based phototransduction system (Feuda et al., 2012; Porter et al., 2012; Ramirez et al., 2016).
Regarding NK homeobox genes, six or seven NK genes probably existed in the last common ancestor of sponges and eumetazoans. The NK cluster in the last common ancestor to protostomes and deuterostomes probably contained a cluster of nine NK genes: Msx, NK1/slouch, NK3/bagpipe, NK4/tinman, Tlx/t-15, NK7, NK6/hgtx, NK5/Hmx, and Lbx j ladybird (Holland 2001, Garcia-Fernandez 2005, Larroux et al.
(25) Erwin and Valentine, near the conclusion of The Cambrian Explosion, remark that "the pathway from sponges to eumetazoans is the most enigmatic [my italics] of any evolutionary transition in metazoans" (p.
2014), these junctions manifested features typical of adherens junctions in eumetazoans, so that here they will be referred to as adherens junctions.