Metazoa comprises 35–40 phyla that include some 1.3 million described species.
Phylogenetic analyses of metazoan interrelationships have progressed in the past two …

Progress in resolving the phylogenetic relationships among animals and the expansion of
molecular developmental studies to a broader variety of organisms has provided important …

A clear picture of animal relationships is a prerequisite to understand how the morphological
and ecological diversity of animals evolved over time. Among others, the placement of the …

SUMMARY microRNAs (miRNAs) are approximately 22‐nucleotide noncoding RNA
regulatory genes that are key players in cellular differentiation and homeostasis. They might …

Most bilaterian animals possess a through gut with a separate mouth and anus. It is
commonly believed that during the transition from radial to bilateral symmetry, both openings …

Geodia species north of 60° N in the Atlantic appeared in the literature for the first time when
Bowerbank described Geodia barretti and G. macandrewii in 1858 from western Norway …

Recent studies on microRNA (miRNA) evolution focused mainly on the comparison of
miRNA complements between animal clades. However, evolution of miRNAs within such …

Background Tissue plasticity and a substantial regeneration capacity based on stem cells
are the hallmark of several invertebrate groups such as sponges, cnidarians and …

Acoela are marine microscopic worms currently thought to be the sister taxon of all other
bilaterians. Acoels have long been used as models in evolutionary scenarios, and …

During the past decade, great progress has been made in clarifying the relationships among
bilaterian animals. Studies based on a limited number of markers established new …