Editing Commensalism (section)

{{Short description|Beneficial symbiosis between species}}
{{use dmy dates |date=May 2023}}
[[File:Echeneis naucrates 241647485.jpg|thumb|upright=1.35|[[Remora]] are specially adapted to attach themselves to larger fish (or other animals, in this case a sea turtle) that provide locomotion and food.]]

'''Commensalism''' is a long-term [[biological interaction]] ([[symbiosis]]) in which members of one [[species]] gain benefits while those of the other species neither benefit nor are harmed.<ref name=wilson1975/> This is in contrast with [[mutualism (biology)|mutualism]], in which both organisms benefit from each other; [[Symbiosis#Amensalism|amensalism]], where one is harmed while the other is unaffected; and [[parasitism]], where one is harmed and the other benefits.

The commensal (the species that benefits from the association) may obtain nutrients, shelter, support, or locomotion from the host species, which is substantially unaffected. The commensal relation is often between a larger host and a smaller commensal; the [[Host (biology)|host]] organism is unmodified, whereas the commensal species may show great structural adaptation consistent with its habits, as in the [[remora]]s that ride attached to [[sharks]] and other fishes. Remoras feed on their hosts' fecal matter,<ref>{{Cite journal|last1=Williams|first1=E. H.|last2=Mignucci-Giannoni|first2=A. A.|last3=Bunkley-Williams|first3=L.|last4=Bonde|first4=R. K.|last5=Self-Sullivan|first5=C.|last6=Preen|first6=A.|last7=Cockcroft|first7=V. G.|date=2003|title=Echeneid-sirenian associations, with information on sharksucker diet|journal=Journal of Fish Biology|language=en|volume=63|issue=5|pages=1176–1183|doi=10.1046/j.1095-8649.2003.00236.x|bibcode=2003JFBio..63.1176W |issn=0022-1112}}</ref> while [[pilot fish]] feed on the leftovers of their hosts' meals. Numerous birds perch on bodies of large mammal [[Herbivore|herbivores]] or feed on the insects turned up by grazing mammals.<ref name=pmid29576981/>