Editing Testicle (section)

===External appearance===
In [[seasonal breeder]]s, the weight of the testes often increases during the breeding season.<ref name="Johnson2012">{{cite book|author=A.D. Johnson|title=Development, Anatomy, and Physiology|url=https://books.google.com/books?id=yAJMlA0FkAUC&q=%22seasonal+breeders%22|date=2 December 2012|publisher=Elsevier|isbn=978-0-323-14323-3|access-date=19 October 2020|archive-date=29 June 2023|archive-url=https://web.archive.org/web/20230629161308/https://books.google.com/books?id=yAJMlA0FkAUC&q=%22seasonal+breeders%22|url-status=live}}</ref> The [[Dromedary#Testicles|testicles of a dromedary camel]] are {{convert|7|-|10|cm|in|abbr=on}} long, {{convert|4.5|cm|in|abbr=on}} deep and {{convert|5|cm|in|abbr=on}} in width. The right testicle is often smaller than the left.<ref name=anatomy>{{cite book|last=Mukasa-Mugerwa|first=E.|title=The Camel (Camelus dromedarius): A Bibliographical Review|pages=11–3}}</ref>

In [[shark]]s, the testicle on the right side is usually larger. In many bird and mammal species, the left may be larger. [[Fish_anatomy#Testes|Fish usually have two testes]] of a similar size. The primitive [[jawless fish]] have only a single testis, located in the midline of the body, although this forms from the fusion of paired structures in the embryo.<ref name=VB/>