Treatise Online, no. 21: Part E, Revised, Volume 4, Chapter 2B: Functional morphology of the fossil hypercalcified chaetetid-type Porifera (Demospongiae)

Treatise Online, no. 36: Part E, Revised, Volume 4, Chapter 2E: Paleoecology of the hypercalcified chaetetid-type Porifera (Demospongiae)

“…However, it is not uncommon to find fossil chaetetids in limestones with phylloid and other algae, as noted in West (2011b). WaHlman (2002, p. 290) stated that upper Carboniferous (Pennsylvanian) chaetetid mounds and banks appear to have formed buttresses around the seaward margins of algal mounds (Fig.…”

“…Once established on the substrate, a rapid rate of expansion, i.e., rapid growth rate, is a significant advantage. The growth rates of extant hypercalcified demosponges is slow (see discussion of growth rates in West, 2011b), and, given that it was likely to be similar in fossil chaetetids, it was not much of an advantage. It is currently unknown whether extant hypercalcified demosponges and/or their fossil ancestors were equipped with allelochemicals and/or secondary metabolites that inhibited, or arrested, the growth of spatial competitors.…”

“…30C). See KeRsHaW (1998, 2012), dasilVa, KeRsHaW, and boulVain (2011a, 2011b, and Webby and KeRsHaW (2011) for details on these and other aspects of stromatoporoid paleoecology.…”