Editing Smooth newt (section)

===Reproduction===

{{external media
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| video1 = ''[https://film.britishcouncil.org/resources/film-archive/the-life-cycle-of-the-newt The life cycle of the newt]'', [[British Council]], 1942. Educational film on the smooth newt (10:08 min).
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[[File:TriturusVulgarisLarva.JPG|thumb|right|alt=Newt larva with feathery gills in side view|Well-developed larva shortly before [[metamorphosis]]]]
[[File:Smooth_Newt_Juveniles_(Lissotriton_vulgaris)_(8618458053).jpg|thumb|right|alt=Two brown juvenile newts sitting closely together|Two juveniles ([[eft]]s) after the transition to land]]

[[Migration (ecology)|Migration]] to the breeding sites occurs as soon as February, but in the northern parts of the range and at higher altitudes, it may not start before summer. After entering the water, the breeding characters, especially the male's crest, take a few weeks to develop.{{r|Sparreboom2014|p=238}}

Mating involves an intricate [[courtship display]]: the male attempts to attract a female by swimming in front of her and sniffing her cloaca. He then vibrates his tail against his body, sometimes violently lashing it, thereby fanning [[pheromones]] towards her. In the final phase, he moves away from her, the tail quivering. If she is still interested, she will follow him and touch his cloaca with her snout, whereupon he deposits a packet of sperm (a [[spermatophore]]). He then guides her over the spermatophore so she picks it up with her cloaca. Males often try to lead females away from displaying competitors.{{r|Sparreboom2014|p=238–240}}

Eggs are fertilised internally, and progeny of one female usually has multiple fathers. Females tend to mate preferentially with unrelated males, probably to avoid [[inbreeding depression]].{{r|Jehle2007}}

Females lay 100–500 eggs, usually folding them into waterplants. The eggs are {{cvt|1.3|–|1.7|mm}} in diameter ({{cvt|2.7|–|4|mm}} with jelly capsule) and light brown to greenish or grey in colour. Larvae typically hatch after 10–20 days, depending on temperature, and metamorphose into terrestrial efts after around three months.{{r|Sparreboom2014|p=238–240}}

[[Paedomorphism]], where adults stay aquatic and retain their gills and skin seams or only resorb them partially, occurs regularly but only in a small proportion of individuals. It does not appear to be determined genetically but favoured by cold water, a low density of individuals and abundant aquatic prey. Wild paedomorphic individuals often metamorphosed when they were transferred into an [[aquarium]].{{r|Grosse2011|p=192–193}}