Sentences with word «bilaterians»

Defining the properties and characteristics of the last common ancestor of bilaterian animals, Urbilateria, is a key question of the evolution and development field (1).

Ancestral state reconstruction suggests that contractile mesodermal midline cells existed in bilaterian ancestors.

Bilaterian origins: Significance of new experimental observations.

Bilaterian phylogeny based on analyses of a region of the sodium - potassium ATPase alpha - subunit gene.

Our analyses support the grouping of placozoans, cnidarians and bilaterians into a eumetazoan clade, with demosponges as an earlier - branching lineage25, and reject the diploblast — triploblast phylogeny17 in favour of a more conventional «sponges first» tree19, 20 (Fig. 1d).

Genetic family tree data suggested that complex animals — known as bilaterians — evolved prior to the Cambrian Period.

In particular, inhibitors described from bilaterians were not found in Amphimedon (for example, Chordin, Numb, I - Smads, Wif).

O. Simakov, F. Marletaz, S. J. Cho, E. Edsinger - Gonzales, P. Havlak, U. Hellsten, D. H. Kuo, T. Larsson, J. Lv, D. Arendt, R. Savage, K. Osoegawa, P. de Jong, J. Grimwood, J. A. Chapman, H. Shapiro, A. Aerts, R. P. Otillar, A. Y. Terry, J. L. Boore, I. V. Grigoriev, D. R. Lindberg, E. C. Seaver, D. A. Weisblat, N. H. Putnam, D. S. Rokhsar, Insights into bilaterian evolution from three spiralian genomes.

«The fossils that we describe were made by quite complex animals that we call bilaterians.

As co-author Hisanori Kohtsuka explains, «because one habitat where X. japonica was found is easily accessible from a marine station, this new species promises to be valuable for future research on bilaterian and deuterostome evolution.»

Amphimedon lacks Hox genes and some other transcription factor subfamilies that are involved in specifying and patterning bilaterian nervous systems and body plans13, 14,27,36,37.

An ancestral state reconstruction based on our data and on a survey of bilaterian musculature (table S3) favored the presence of an axochord in protostome ancestors (fig.

Orphan worms and, homeless parasites enhance bilaterian diversity.

Late Precambrian bilaterians: grades and clades.

Acoel flatworms: earliest extant bilaterian metzoans, not members of platyhelminthes.

A phylogenetic analysis of myosin heavy chain type II sequences corroborates that Acoela and Nemertodermatida are basal bilaterians.

Hox clusters and bilaterian phylogeny.

Unlike sponges, comb jellies (or ctenophores) have a primitive nervous system, are hungry predators and have complex cells also found in bilaterians — the group of animals, including humans, that have fronts, backs, an upside and a downside.

Multigene analyses of bilaterian animals corroborate the monophyly of Ecdysozoa, Lophotrochozoa, and Protostomia.

Most fossils of bilaterian animals are younger, first appearing in the Cambrian period.»

«Although we saw some of the hallmark characteristics of bilateral growth and development, we don't believe Dickinsonia was a precursor to today's bilaterians, rather that these are two distinct groups that shared a common set of ancestral genes that are present throughout the animal lineage,» Evans said.

The accumulation of new modules, by a process called terminal addition, suggests that Dickinsonia developed in a related way to bilaterians, a complex group that display bilateral symmetry, including animals ranging from flies and worms to humans.

However, the researchers do not believe Dickinsonia was ancestrally related to bilaterians, since it lacked other features that most bilaterians share, most notably a mouth, gut and anus.

According to this view, early sponges sit at the base of the animal tree of life, which then forks into four other groups: comb jellies, jellyfish, primitive multicellular animals called placazoa, and another group of early symmetrical animals that led to worms, insects, and ultimately us (bilaterians).

The finding suggests that bilaterians may have lived as early as 550 million years ago, during the late Ediacaran Period.