Editing Biological interaction (section)

=== Long-term interactions (symbioses) ===

{{main|Symbiosis}}

[[File:Symbiotic relationships diagram.svg|thumb|upright=2|The six possible types of [[symbiosis|symbiotic relationship]], from mutual benefit to mutual harm]]

The six possible types of [[symbiosis]] are mutualism, commensalism, parasitism, neutralism, amensalism, and competition.<ref>*{{citation |last=Douglas |first=Angela |title=The Symbiotic Habit |publisher=Princeton University Press |location=New Jersey |year=2010 |isbn=978-0-691-11341-8 |pages=5–12}}</ref> These are distinguished by the degree of benefit or harm they cause to each partner.<ref>{{cite journal |last1=Wootton |first1=J.T. |last2=Emmerson |first2=M. |title=Measurement of Interaction Strength in Nature |journal=[[Annual Review of Ecology, Evolution, and Systematics]] |volume=36 |pages=419–444 |year=2005 |jstor=30033811 |doi=10.1146/annurev.ecolsys.36.091704.175535}}</ref>

==== Mutualism ====

{{main|Mutualism (biology)}}

Mutualism is an interaction between two or more species, where species derive a mutual benefit, for example an increased [[carrying capacity]]. Similar interactions within a species are known as [[Co-operation (evolution)|co-operation]]. Mutualism may be classified in terms of the closeness of association, the closest being symbiosis, which is often confused with mutualism. One or both species involved in the interaction may be [[wikt:obligate|obligate]], meaning they cannot survive in the short or long term without the other species. Though mutualism has historically received less attention than other interactions such as predation,<ref name="Begon96">Begon, M., J.L. Harper and C.R. Townsend. 1996. ''Ecology: individuals, populations, and communities'', Third Edition. Blackwell Science, Cambridge, Massachusetts.</ref> it is an important subject in ecology. Examples include [[cleaning symbiosis]], [[gut flora]], [[Müllerian mimicry]], and [[nitrogen fixation]] by bacteria in the root nodules of [[legumes]].{{cn|date=May 2023}}

==== Commensalism ====

{{main|Commensalism}}

Commensalism benefits one organism and the other organism is neither benefited nor harmed. It occurs when one organism takes benefits by interacting with another organism by which the host organism is not affected. A good example is a [[remora]] living with a [[manatee]]. Remoras feed on the manatee's faeces. The manatee is not affected by this interaction, as the remora does not deplete the manatee's resources.<ref name="Echeneid-sirenian associations, with information on sharksucker diet">{{cite journal |last1=Williams E, Mignucci, Williams L & Bonde |title=Echeneid-sirenian associations, with information on sharksucker diet |journal=Journal of Fish Biology |date=November 2003 |volume=5 |issue=63 |pages=1176–1183 |doi=10.1046/j.1095-8649.2003.00236.x |bibcode=2003JFBio..63.1176W |url=https://www.researchgate.net/publication/253117307 |access-date=17 June 2020}}</ref>

==== Parasitism ====

{{main|Parasitism}}

Parasitism is a relationship between species, where one organism, the [[parasite]], lives on or in another organism, the [[Host (biology)|host]], causing it some harm, and is [[adaptation (biology)|adapted]] structurally to this way of life.<ref>{{cite book | last=Poulin | first=Robert | author-link=Robert Poulin (zoologist) | title=Evolutionary Ecology of Parasites | publisher=Princeton University Press | year=2007 | isbn=978-0-691-12085-0 | pages=[https://archive.org/details/evolutionaryecol0000poul/page/4 4–5] | url=https://archive.org/details/evolutionaryecol0000poul/page/4 }}</ref> The parasite either feeds on the host, or, in the case of intestinal parasites, consumes some of its food.<ref>{{cite journal |title=Current usage of symbiosis and associated terminology |last1=Martin |first1= Bradford D. |last2= Schwab |first2=Ernest |year=2013 |journal=International Journal of Biology |volume=5 |issue=1 |pages=32–45 |doi=10.5539/ijb.v5n1p32|doi-access=free }}</ref>

==== Neutralism ====

Neutralism (a term introduced by [[Eugene Odum]])<ref>Toepfer, G. "Neutralism". In: ''BioConcepts''. [http://www.biological-concepts.com/views/search.php?term=1441 link].</ref> describes the relationship between two species that interact but do not affect each other. Examples of true neutralism are virtually impossible to prove; the term is in practice used to describe situations where interactions are negligible or insignificant.<ref>(Morris et al., 2013)</ref><ref>{{Cite journal |last=Lidicker |first=William Z. |date=1979 |title=A Clarification of Interactions in Ecological Systems |url=https://www.jstor.org/stable/1307540 |journal=BioScience |volume=29 |issue=8 |pages=475–477 |doi=10.2307/1307540 |jstor=1307540 |issn=0006-3568}}</ref>

==== Amensalism ====

{{further|Amensalism}}
[[File:Eucalypts inhibiting grass growth example of amensalism and allelopathy.jpg|thumb|Leaf litter from these eucalypts contains chemicals which inhibit grass growth near the trees]]
[[Amensalism]] (a term introduced by [[Edward Haskell]])<ref>Toepfer, G. "Amensalism". In: ''BioConcepts''. [http://www.biological-concepts.com/views/search.php?term=1440 link].</ref> is an interaction where an organism inflicts harm to another organism without any costs or benefits received by itself.<ref name="Willey, Joanne M. 2011">{{cite book |last1=Willey |first1=Joanne M. |last2=Sherwood |first2=Linda M. |last3=Woolverton |first3=Cristopher J. |year=2013 |title=Prescott's Microbiology |edition=9th |pages=713–38 |isbn=978-0-07-751066-4}}</ref> This unidirectional process can be based on the release of one or more chemical compounds by one organism that negatively affect another, called [[allelopathy]].<ref>{{Citation |last1=Scavo |first1=Aurelio |title=Allelopathy: Principles and Basic Aspects for Agroecosystem Control |date=2018 |work=Sustainable Agriculture Reviews 28: Ecology for Agriculture |pages=47–101 |editor-last=Gaba |editor-first=Sabrina |url=https://link.springer.com/chapter/10.1007/978-3-319-90309-5_2 |access-date=2025-04-18 |place=Cham |publisher=Springer International Publishing |language=en |doi=10.1007/978-3-319-90309-5_2 |isbn=978-3-319-90309-5 |last2=Restuccia |first2=Alessia |last3=Mauromicale |first3=Giovanni |editor2-last=Smith |editor2-first=Barbara |editor3-last=Lichtfouse |editor3-first=Eric}}</ref> One example of this is the microbial production of antibiotics that can inhibit or kill other, susceptible microorganisms. Another example is leaf litter from trees such as ''[[Pinus ponderosa]]''<ref>{{Cite journal |last1=Singh |first1=Surendra P. |last2=Inderjit |last3=Singh |first3=Jamuna S. |last4=Majumdar |first4=Sudipto |last5=Moyano |first5=Jaime |last6=Nuñez |first6=Martin A. |last7=Richardson |first7=David M. |date=2018 |title=Insights on the persistence of pines (Pinus species) in the Late Cretaceous and their increasing dominance in the Anthropocene |journal=Ecology and Evolution |language=en |volume=8 |issue=20 |pages=10345–10359 |doi=10.1002/ece3.4499 |issn=2045-7758 |pmc=6206191 |pmid=30398478|bibcode=2018EcoEv...810345S }}</ref> or ''[[Eucalyptus|Eucalyptus spp.]]''<ref>{{Cite journal |last1=Chu |first1=Chaojun |last2=Mortimer |first2=P. E. |last3=Wang |first3=Hecong |last4=Wang |first4=Yongfan |last5=Liu |first5=Xubing |last6=Yu |first6=Shixiao |date=2014-07-01 |title=Allelopathic effects of Eucalyptus on native and introduced tree species |url=https://www.sciencedirect.com/science/article/abs/pii/S0378112714001492 |journal=Forest Ecology and Management |volume=323 |pages=79–84 |doi=10.1016/j.foreco.2014.03.004 |bibcode=2014ForEM.323...79C |issn=0378-1127}}</ref> preventing the establishment and growth of other plant species.

A clear case of amensalism is where [[Ungulate|hoofed mammals]] trample grass. Whilst the presence of the grass causes negligible detrimental effects to the animal's hoof, the grass suffers from being crushed. Amensalism also includes strongly asymmetrical competitive interactions, such as has been observed between the Spanish [[ibex]] and [[Weevil|weevils]] of the genus ''[[Timarcha]],'' which both feed upon the same type of shrub. Whilst the presence of the weevil has almost no influence on food availability, the presence of ibex has an enormous detrimental effect on weevil numbers, as they eat the shrub and incidentally ingest the weevils.<ref name="Gómez J., González-Megías A. 2002">{{cite journal |last1=Gómez |first1=José M. |last2=González-Megías |first2=Adela |year=2002 |title=Asymmetrical interactions between ungulates and phytophagous insects: Being different matters |journal=Ecology |volume=83 |issue=1 |pages=203–11 |doi=10.1890/0012-9658(2002)083[0203:AIBUAP]2.0.CO;2}}</ref>

==== Competition ====

{{main|Competition (biology)}}

[[File:Hirschkampf.jpg|thumb|Male-male interference competition in [[red deer]]]]

Competition can be defined as an interaction between [[organism]]s or species, in which the [[fitness (biology)|fitness]] of one is lowered by the presence of another. Competition is often for a resource such as [[food]], [[water]], or [[territory (animal)|territory]] in [[Limiting factor|limited]] supply, or for access to females for reproduction.<ref name="Begon96"/> Competition among members of the same species is known as [[intraspecific competition]], while competition between individuals of different species is known as [[interspecific competition]]. According to the [[competitive exclusion principle]], species less suited to compete for resources should either [[adaptation|adapt]] or [[extinction|die out]].<ref name=hardin60>{{cite journal |author=Hardin, Garrett |title=The competitive exclusion principle |journal=Science |volume=131 |pages=1292–1297 |issue=3409 |year=1960 |url=http://www.esf.edu/efb/schulz/seminars/hardin.pdf |doi=10.1126/science.131.3409.1292 |pmid=14399717 |bibcode=1960Sci...131.1292H |access-date=2018-10-04 |archive-date=2017-11-17 |archive-url=https://web.archive.org/web/20171117235048/http://www.esf.edu/efb/schulz/seminars/hardin.pdf |url-status=dead }}</ref><ref name=Pocheville2015>{{cite book | last=Pocheville | first=Arnaud | year=2015 | chapter=The Ecological Niche: History and Recent Controversies | chapter-url=https://www.academia.edu/6188833 | editor1-last=Heams | editor1-first=Thomas | editor2-last=Huneman | editor2-first=Philippe | editor3-last=Lecointre | editor3-first=Guillaume |display-editors=3 | editor4-last=Silberstein | editor4-first=Marc | title=Handbook of Evolutionary Thinking in the Sciences | location=Dordrecht | publisher=Springer | publication-date=2015 | pages=547–586 | isbn=978-94-017-9014-7}}</ref> This competition within and between species for resources plays a critical role in [[natural selection]].<ref name="SahneyBentonFerry2010LinksDiversityVertebrates">{{cite journal |last1=Sahney |first1=Sarda |last2=Benton |first2=Michael J. |author-link2=Michael Benton |last3=Ferry |first3=Paul A. |date=23 August 2010 |title=Links between global taxonomic diversity, ecological diversity and the expansion of vertebrates on land |journal=[[Biology Letters]] |volume=6 |issue=4 |pages=544–547 |doi=10.1098/rsbl.2009.1024 |pmc=2936204 |pmid=20106856 }}</ref>