Abstract Cnidarians are phylogenetically located near the base of ‘tree animals’, and their early evolution had a profound impact on rise bilaterians. However, diversity phylogeny this ‘lowly’ metazoan clade has hitherto been enigmatic. Fortunately, cnidarian fossils from Cambrian could provide key insights into evolutionary history. Here, based scrutiny purported hyolith Burithes yunnanensis H...

The fossilization of organic remains and shell material by calcium phosphate minerals provides an illuminating, but time-bounded, window into Ediacaran–Cambrian animal evolution. For reasons that remain unknown, phosphatic fossil preservation declined signifi cantly through Cambrian Series 2. Here, we investigate the phosphorus (P) sources for phosphatic Cambrian carbonates, presenting sediment...

In a series of previous papers, we studied sortable elements in finite Coxeter groups, and the related Cambrian fans. We applied sortable elements and Cambrian fans to the study of cluster algebras of finite type and the noncrossing partitions associated to Artin groups of finite type. In this paper, as the first step towards expanding these applications beyond finite type, we study sortable el...

The study area is a part of so-called Sanandaj-Sirjan zone or Zagros imbricate zone of the Zagros Orogen, Iran. The Hamedan region comprises a metamorphic sequence of low- to high-grade regional and contact metamorphic rocks intruded by mafic, intermediate and felsic plutonic bodies. The sequence comprises pelitic, psammitic, mafic, calc-pelitic and calc-silicate rocks.  Pelitic rocks are the m...

A dramatic shift in microbial reefs occurred around the Ediacaran–Cambrian boundary. Here we describe changes composition, construction, and texture of Zavkhan Terrane Gobi-Altai Province, western Mongolia, during late Ediacaran early Cambrian. Stromatolites consisting peloids, micritic clots, homogeneous lime mud without calcified microbes (calcimicrobes) are characteristic upper (units 9 16A ...

A new eucrustacean arthropod, Wujicaris muelleri gen. et sp. nov, is represented by a Lower Cambrian early metanauplius of strikingly modern morphology despite being the oldest known fossil of such an early immature crustacean larva. The morphology of the metanauplius closely mirrors that of corresponding developmental stages of living barnacles and copepods, and it is likely that its appendage...