Editing Cecum (section)

==Other animals==
[[File:Gastric caeca of dissected cockroach.tiff|thumb|Gastric cecum of dissected [[cockroach]].  Scale bar, 2 mm.]]

A cecum is present in most [[amniote]] species, and also in [[lungfish]], but not in any living species of [[amphibian]]. In [[reptile]]s, it is usually a single median structure, arising from the dorsal side of the large intestine. [[Bird]]s typically have two paired ceca, as do, unlike other mammals, [[hyrax]]es.<ref name=VB>{{cite book |last1=Romer |first1=Alfred Sherwood |last2=Parsons |first2=Thomas S. |year=1977 |title=The Vertebrate Body |publisher=Holt-Saunders International |location=Philadelphia |pages=353–54 |isbn=978-0-03-910284-5 }}</ref> Parrots do not have ceca.<ref name=MP>{{cite journal |last1=Clench |first1=Mary H. |last2=Mathias |first2=John R. |title=The Avian Cecum: A Review |journal=The Wilson Bulletin |date=1995 |volume=107 |issue=1 |pages=93–121 |id={{Gale|A16787963}} {{INIST|3480481}} |jstor=4163516 }}</ref>

Most mammalian [[herbivore]]s have a relatively large cecum.  In many species, it is considerably wider than the colon. For some herbivores such as [[lagomorpha|lagomorphs]] (rabbits, hares, pikas), easily digestible food is processed in the gastrointestinal tract and expelled as regular feces.  But in order to get nutrients out of hard to digest fiber, lagomorphs ferment fiber in the cecum and then expel the contents as [[cecotrope]]s, which are reingested (cecotrophy).  The cecotropes are then absorbed in the small intestine to utilize the nutrients.

In contrast, obligate [[carnivore]]s, whose diets contain little or no plant matter, have a reduced cecum, which is often partially or wholly replaced by the [[appendix (anatomy)|appendix]].<ref name=VB/> Mammalian species which do not develop a cecum include [[raccoon]]s,<ref>{{cite journal |last1=Clemens |first1=Edgar T. |last2=Stevens |first2=Charles E. |title=Sites of Organic Acid Production and Patterns of Digesta Movement in the Gastro-Intestinal Tract of the Raccoon |journal=The Journal of Nutrition |date=1 June 1979 |volume=109 |issue=6 |pages=1110–1116 |doi=10.1093/jn/109.6.1110 |pmid=448450 |url=https://www.sciencedirect.com/science/article/abs/pii/S0022316623277147 |access-date=1 June 2024 |issn=0022-3166}}</ref> [[bear]]s,<ref>{{cite journal |last1=Jones |first1=James D. |last2=Zollman |first2=Paul E. |title=Black Bear (Ursus americanus) Bile Composition: Seasonal Changes |journal=Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology |date=17 March 1997 |volume=118 |issue=3 |pages=387–390 |doi=10.1016/S0742-8413(97)00176-X |pmid=9467890 |url=https://www.sciencedirect.com/science/article/abs/pii/S074284139700176X |access-date=1 June 2024}}</ref> and the [[red panda]].<ref>{{cite journal |last1=Wei |first1=F. |last2=Feng |first2=Z. |last3=Wang |first3=Z. |last4=Zhou |first4=A. |last5=Hu |first5=J. |title=Nutrient and energy requirements of red panda (Ailurus fulgens) during lactation |journal=Mamm |date=1 January 1999 |volume=63 |issue=1 |pages=3–10 |doi=10.1515/mamm.1999.63.1.3 |url=https://www.degruyter.com/document/doi/10.1515/mamm.1999.63.1.3/html |access-date=1 June 2024 |language=en |issn=1864-1547}}</ref>

Many fish have a number of small outpockets, called ''pyloric ceca'', along their intestine; despite the name, they are not [[homology (biology)|homologous]] with the cecum of amniotes – their purpose is to increase the overall area of the digestive epithelium.<ref name=VB/> Some invertebrates, such as squid,<ref name=Williams1910>{{cite book |last1=Williams |first1=Leonard Worcester |title=The anatomy of the common squid : ''Loligo pealii'', Lesueur |date=1910 |doi=10.5962/bhl.title.27291 |oclc=697639284 |url=https://www.biodiversitylibrary.org/item/69772 }}</ref> may also have structures with the same name, but these have no relationship with those of vertebrates.