That included bilaterian
animals, which have bodies that can be divided into different sides - right and left, top and bottom, back and front.
Our phytogeny confirms earlier studies that the Araneae spiders contain opsins from three of the nine major opsin lineages present in the bilaterian
ancestor (Ramirez et al.
These genes are believed to have diversified before the last common bilaterian
ancestor (Brooke et al.
The dawn of bilaterian
animals: the case of the acoelomorph flatworms.
This mechanism of transcriptional regulation provides a plausible explanation for the conservation of this bi-gene cluster among the bilaterian
The biological identity of these burrowing organisms is unknown, although they were clearly bilaterian
Along with other U of A researchers, the team determined that the tracks were made by a primitive animal called a bilaterian
, which is distinguished from other non-animal, simple life forms by its symmetry-its topside is distinguishable from its bottom side-and a unique set of 'footprints'.
Evidence for the presence of a cellulase gene in the last common ancestor of bilaterian
From the basic bilaterian
plan, two developmental groups of organisms evolved namely deuterostomes (echinoderms and chordates) and the protostones (almost everything else).
Multigene analyses of bilaterian
animals corroborate the monophyly of ecdysozoa, lophotrochozoa, and protostomia.
About 70% of eye genes are commonly expressed in vertebrates and octopus, and 97% of these are estimated to have occurred in the ancestral bilaterian
Early Cambrian trace fossils reflect the diversification of bilaterian
animals, exhibiting a degree of morphological diversity, complexity and depth of infaunal habitation exceeding that of terminal Proterozoic (Vendian) trace fossils (e.