Search results
Results from the WOW.Com Content Network
Bilateria (/ ˌ b aɪ l ə ˈ t ɪər i ə /) [5] is a large clade of animals characterised by bilateral symmetry during embryonic development. This means their body plans are laid around a longitudinal axis with a front (or "head") and a rear (or "tail") end, as well as a left–right–symmetrical belly ( ventral ) and back ( dorsal ) surface.
Bilateria is an extremely diverse group of animals containing a vast majority of its species, largely due to the enormous amount of arthropods. This article is a list of orders contained within Bilateria separated by phylum.
Its appearance is a matter of debate, for no representative has been (or may or may not ever be) identified in the fossil record.Two reconstructed urbilaterian morphologies can be considered: first, the less complex ancestral form forming the common ancestor to Xenacoelomorpha and Nephrozoa; and second, the more complex urbilaterian ancestral to both protostomes and deuterostomes, sometimes ...
Bilateria, one of the five major lineages of animals, is split into two groups; the protostomes and deuterostomes. Deuterostomes consist of chordates (which include the vertebrates) and ambulacrarians. [20] It seems likely that the Kimberella was a member of the protostomes.
Most living animal species belong to the infrakingdom Bilateria, a highly proliferative clade whose members have a bilaterally symmetric and significantly cephalised body plan, and the vast majority of bilaterians belong to two large superphyla: the protostomes, which includes organisms such as arthropods, molluscs, flatworms, annelids and ...
This zoology –related article is a stub. You can help Wikipedia by expanding it.
Usually, "Planulozoa" is a Cnidaria–Bilateria clade that excludes Placozoa. [11] Otherwise, when including all three lineages, it is synonymous with Parahoxozoa. [22] Triploblasty may have developed before the Cnidaria–Bilateria radiation. [23]
Vetulicolia is a group of bilaterian marine animals encompassing several extinct species from the Cambrian, [2] and possibly Ediacaran, [1] periods. As of 2023, the majority of workers favor placing Vetulicolians in the stem group of the Chordata, [3] but some continue to favor a more crownward placement as a sister group to the Tunicata. [2]