Editing Demosponge (section)

===Meiosis and recombination===

The cytological progression of [[sponge|porifera]] [[oogenesis]] and [[spermatogenesis]] ([[gametogenesis]]) shows great similarity to other metazoa.<ref name = Koutsouveli2020>{{cite journal |vauthors=Koutsouveli V, Cárdenas P, Santodomingo N, Marina A, Morato E, Rapp HT, Riesgo A |title=The Molecular Machinery of Gametogenesis in Geodia Demosponges (Porifera): Evolutionary Origins of a Conserved Toolkit across Animals |journal=Mol Biol Evol |volume=37 |issue=12 |pages=3485–3506 |date=December 2020 |pmid=32929503 |pmc=7743902 |doi=10.1093/molbev/msaa183 }}</ref>  Most of the genes from the classic set of [[meiosis|meiotic]] genes conserved in [[eukaryote]]s are upregulated in the sponges ''[[Geodia hentscheli]]'' and ''Geodia phlegraei'' including genes for DNA [[genetic recombination|recombination]].<ref name = Koutsouveli2020/>   Since porifera are the earliest divergent animals, these findings indicate that the basic toolkit of meiosis and recombination were present early in eukaryote evolution.<ref name = Koutsouveli2020/>