Editing Coelacanth (section)

== Life cycle ==
[[File:Latimeria chalumnae embryo.jpg|thumb|''Latimeria chalumnae'' embryo with its yolk sac from the [[Muséum national d'histoire naturelle]]]]
[[File:Coelacanth_egg.jpg|thumb|upright=0.75|''Latimeria chalumnae'' egg]]
Coelacanths are [[ovoviviparous]], meaning that the female retains the fertilized eggs within her body while the embryos develop during a gestation period of five years. Typically, females are larger than the males; their scales and the skin folds around the [[cloaca]] differ. The male coelacanth has no distinct copulatory organs, just a cloaca, which has a [[Genital papilla|urogenital papilla]] surrounded by erectile [[Wattle (anatomy)|caruncles]]. It is hypothesized that the cloaca everts to serve as a copulatory organ.<ref name="ref1" />{{rp|27}}<ref name="ref2" />

Coelacanth eggs are large, with only a thin layer of membrane to protect them. Embryos hatch within the female and eventually are born alive, which is a rarity in fish. This was only discovered when the American Museum of Natural History dissected its first coelacanth specimen in 1975 and found it pregnant with five embryos.<ref>{{cite web|title = The Coelacanth: Five Fast Facts|url = http://www.amnh.org/explore/news-blogs/from-the-collections-posts/the-coelacanth-five-fast-facts|website = AMNH|access-date = 2015-10-28}}</ref> Young coelacanths resemble the adult, the main differences being an external yolk sac, larger eyes relative to body size and a more pronounced downward slope of the body. The juvenile coelacanth's broad yolk sac hangs below the pelvic fins. The scales and fins of the juvenile are completely matured; however, it does lack [[odontode]]s, which it gains during maturation.<ref name="ref2" />

A study that assessed the paternity of the embryos inside two coelacanth females indicated that each clutch was sired by a single male.<ref>{{Cite journal|title = Single-male paternity in coelacanths|journal = Nature Communications|volume = 4|page = 2488|doi = 10.1038/ncomms3488|pmid = 24048316|year = 2013|last1 = Lampert|first1 = Kathrin P.|last2 = Blassmann|first2 = Katrin|last3 = Hissmann|first3 = Karen|last4 = Schauer|first4 = Jürgen|last5 = Shunula|first5 = Peter|last6 = Kharousy|first6 = Zahor el|last7 = Ngatunga|first7 = Benjamin P.|last8 = Fricke|first8 = Hans|last9 = Schartl|first9 = Manfred|bibcode = 2013NatCo...4.2488L|url = http://oceanrep.geomar.de/22046/1/Lampert%20etal_coelacanth-paternity_NatureComms_2013.pdf}}</ref> This could mean that females mate [[monandrous]]ly, i.e. with one male only. [[Polyandry in nature|Polyandry]], female mating with multiple males, is common in both plants and animals and can be advantageous (e.g. insurance against mating with an infertile or incompatible mate), but also confers costs (increased risk of infection, danger of falling prey to predators, increased energy input when searching for new males).{{citation needed|date=December 2021}}