Editing Insectivore (section)

{{short description|Organism which eats insects}}
{{for|the now-abandoned mammal taxon|Insectivora}}
{{EngvarB|date=July 2022}}
{{Use dmy dates|date=July 2022}}

[[File:Aardwolfskull.jpg|thumb|This [[aardwolf]] skull exhibits greatly reduced [[Molar (tooth)|molars]] and [[carnassial]]s teeth as they are unnecessary for any large, insectivorous animal subsisting on soft insects such as [[termite]]s. The [[dentition]] of a [[shrew]] is very different. The aardwolf uses its [[canine teeth]] in self-defence; accordingly, they have not been greatly reduced.]]
[[file:Common brown robberfly with prey.jpg|thumb|A [[Asilidae|robber fly]] eating a [[hoverfly]]]]
[[File:Myresluger2.jpg|thumb|The [[giant anteater]], a large insectivorous mammal]]

An '''insectivore''' is a [[carnivore|carnivorous]] animal or plant which eats  [[insect]]s.<ref>{{cite web |url=http://wordnetweb.princeton.edu/perl/webwn?s=insectivorous |title=Article for ''insectivorous'' |author=Miller, George A. |year=2009 |website=WordNet |publisher=Princeton University |access-date=1 April 2010}}</ref> An alternative term is '''entomophage''',<ref>{{cite book |last1=Gullan |first1=P.J. |last2=Cranston |first2=P.S. |title = The Insects: An outline of entomology |year=2005 |publisher=[[Blackwell Publishing]] |place=[[Malden, Massachusetts|Malden, MA]] |isbn=978-1-4051-1113-3 |page=455 |url=https://archive.org/details/isbn_9781405111133/page/455}}</ref> which can also refer to the [[Entomophagy in humans|human practice of eating insects]].

The first vertebrate insectivores were [[amphibian]]s. When they [[evolved]] 400&nbsp;million years ago, the first amphibians were [[piscivores]], with numerous sharp conical teeth, much like a modern [[crocodile]]. The same tooth arrangement is however also suited for eating animals with [[exoskeleton]]s, thus the ability to eat insects can stem from piscivory.<ref name="SahneyBentonFerry2010RainforestCollapse">{{cite journal |author1=Sahney, S. |author2=Benton, M.J. |author3=Falcon-Lang, H.J. |year=2010 |title=Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica |journal=Geology |volume=38 |issue=12 |pages=1079–1082 |doi=10.1130/G31182.1 |bibcode=2010Geo....38.1079S |url=http://geology.geoscienceworld.org/cgi/content/abstract/38/12/1079 |format=PDF|url-access=subscription }}</ref>

At one time, insectivorous [[mammal]]s were [[scientific classification|scientifically classified]] in an [[order (biology)|order]] called [[Insectivora]]. This order is now abandoned, as not all insectivorous mammals are closely related. Most of the Insectivora [[taxa]] have been reclassified; those that have not yet been reclassified and found to be truly related to each other remain in the order [[Eulipotyphla]].

Although individually small, insects exist in enormous numbers. Insects make up a very large part of the animal biomass in almost all non-marine, non-polar environments. It has been estimated that the global insect biomass is in the region of 10<sup>12</sup>&nbsp;kg (one [[billion]] tons) with an estimated [[population]] of 10<sup>18</sup> (one billion billion, or [[quintillion]]) organisms.<ref>{{cite book |title=The Biomechanics of Insect Flight: Form, function, evolution |last=Dudley |first=Robert |year=2002 |publisher=[[Princeton University Press]] |chapter=Flight and the Pterygote Insecta |pages=3–35 |isbn=978-0-691-09491-5 |chapter-url=https://books.google.com/books?id=hTIMhD9BF1kC&pg=PA13}}</ref>{{rp|page=13}} Many creatures depend on insects for their primary diet, and many that do not (and are thus not technically insectivores) nevertheless use insects as a [[protein]] supplement, particularly when they are breeding.<ref name="cascades">{{cite book |title=Field Guide to the Cascades & Olympics| year=2004 |publisher=The Mountaineers Books |isbn=978-0-89886-808-1 |pages=317 |url=https://books.google.com/books?id=5YQsJTwkD2AC |access-date=2010-04-01 |author1=Whitney, Stephen R. |author2=Sandelin, R.}}</ref>