Editing Sponge (section)

===Meiosis===

The cytological progression of porifera [[oogenesis]] and [[spermatogenesis]] ([[gametogenesis]]) is very similar to that of other metazoa.<ref name="Koutsouveli_2020">{{cite journal |last1=Koutsouveli |first1=Vasiliki |last2=Cárdenas |first2=Paco |last3=Santodomingo |first3=Nadiezhda |last4=Marina |first4=Anabel |last5=Morato |first5=Esperanza |last6=Rapp |first6=Hans Tore |last7=Riesgo |first7=Ana |title=The Molecular Machinery of Gametogenesis in Geodia Demosponges (Porifera): Evolutionary Origins of a Conserved Toolkit across Animals |journal=Molecular Biology and Evolution |volume=37 |issue=12 |date=16 December 2020 |issn=0737-4038 |pmid=32929503 |pmc=7743902 |doi=10.1093/molbev/msaa183 |pages=3485–3506}}</ref> Most of the genes from the classic set of [[meiosis|meiotic]] genes, including genes for DNA recombination and double-strand break repair, that are conserved in [[eukaryote]]s are expressed in the sponges (e.g. ''[[Geodia hentscheli]]'' and ''Geodia phlegraei'').<ref name="Koutsouveli_2020"/> Since porifera are considered to be the earliest divergent animals, these findings indicate that the basic toolkit of meiosis including capabilities for recombination and DNA repair were present early in eukaryote evolution.<ref name="Koutsouveli_2020"/>

==== Life cycle ====
[[File:Bathymetrical range of selected sponge species.jpg|thumb|upright=1.5|right|Bathymetrical range of some sponge species.<ref>{{cite journal |last=Łukowiak |first=M. |title=Utilizing sponge spicules in taxonomic, ecological and environmental reconstructions: a review |journal=PeerJ |volume=8 |pages=e10601 |date=18 December 2020 |pmid=33384908 |pmc=7751429 |doi=10.7717/peerj.10601 |doi-access=free }}</ref> Demosponge ''[[Samus anonymus]]'' (up to 50&nbsp;m), [[hexactinellid]] ''Scleroplegma lanterna'' (~100–600&nbsp;m), hexactinellid ''Aulocalyx irregularis'' (~550–915&nbsp;m), lithistid demosponge ''Neoaulaxinia persicum'' (~500–1700&nbsp;m)]]

Sponges in [[temperate]] regions live for at most a few years, but some [[Tropics|tropical]] species and perhaps some deep-ocean ones may live for 200&nbsp;years or more. Some calcified [[demosponge]]s grow by only {{convert|0.2|mm|in|abbr=on}} per year and, if that rate is constant, specimens {{convert|1|m|ft|abbr=on}} wide must be about 5,000&nbsp;years old. Some sponges start sexual reproduction when only a few weeks old, while others wait until they are several years old.<ref name="Ruppert_2004"/>