The origin of the ecosystem of hardgrounds and the Ordovician benthic radiation

A hardground ecosystem first appeared at the end of the Cambrian and was established by the beginning of the Ordovician. This corresponded to the emergence of positive feedbacks between the hardground's extension and the increase in quantity of the inhabited benthos. Rapid discovery and occupation of the new ecological niches promoted earlier maturity of the individuals in various benthic groups and facilitated paedomorphic changes in their ontogeny.