This stage in the metazoan was when the first forms of multicellular life started to appear. These were more complex fauna which displayed a variety of subtle changes to there predecessors. This period is the first chance we get to see the appearance of predators and this is displayed by the cirtan fauna by the evolution of protective sheels or skin. Most of the fauna in this time where what paleontologists like to describe as "evolutionary experiments, those that didn't work were soon to die and those that did adapted further protection. The use of calcareous sheel casings is the first of many form of protection adapted in this period.