Editing Microbial ecology (section)

=== Commensalism ===
Commensalism is very common in microbial world, literally meaning "eating from the same table".<ref>{{Citation|last1=Bogitsh|first1=Burton J.|title=Symbiosis and Parasitism|date=2013|work=Human Parasitology|pages=1–13|publisher=Elsevier|isbn=978-0-12-415915-0|last2=Carter|first2=Clint E.|last3=Oeltmann|first3=Thomas N.|doi=10.1016/b978-0-12-415915-0.00001-7|s2cid=88750087}}</ref> It is a relationship between two species where one species benefits with no harm or benefit for the other species.<ref name="annualreviews.org" />  Metabolic products of one microbial population are used by another microbial population without either gain or harm for the first population. There are many "pairs "of microbial species that perform either oxidation or reduction reaction to the same chemical equation. For example, methanogens produce methane by reducing CO<sub>2</sub> to CH<sub>4</sub>, while [[methanotroph]]s oxidise methane back to CO<sub>2</sub>.<ref>{{Citation|last1=Canfield|first1=Donald E.|title=Structure and Growth of Microbial Populations|date=2005|work=Advances in Marine Biology|pages=23–64|publisher=Elsevier|isbn=978-0-12-026147-5|last2=Erik Kristensen|last3=Bo Thamdrup|doi=10.1016/s0065-2881(05)48002-5}}</ref>