The question is if &quot;Mosquitoes fill an important niche in a great many ecologies&quot;.<p>The Nature article that ak217 linked to describes the north as the primary special case: &quot;Taken all together, then, mosquitoes would be missed in the Arctic — but is the same true elsewhere?&quot;<p>Otherwise, they don&#x27;t seem to have a key niche, eg, as a food source for insect-eaters.<p>&gt; Ultimately, there seem to be few things that mosquitoes do that other organisms can&#x27;t do just as well — except perhaps for one. They are lethally efficient at sucking blood from one individual and mainlining it into another, providing an ideal route for the spread of pathogenic microbes.<p>It ends with a quote:<p>&gt; &quot;They don&#x27;t occupy an unassailable niche in the environment,&quot; says entomologist Joe Conlon, of the American Mosquito Control Association in Jacksonville, Florida. &quot;If we eradicated them tomorrow, the ecosystems where they are active will hiccup and then get on with life. Something better or worse would take over.&quot;<p>Thus, the article argues that mosquitoes <i>do not</i> fill an important niche in <i>a great many ecologies</i>, though they definitely fill an important niche in the arctic.