Though its actual function is still a mystery, the broadly expressed Or83b has been conserved across highly divergent insect populations across 250 million years of evolution.
Or83b mutation disrupts behavioral and electrophysiological responses to many odorants, which supports the second model that OR plays a general rather than specific role in olfaction.
When mutating the Or83b gene, larval Drosophila do not travel towards an area of ethyl acetate which is an important odorant related to rotting fruit.
[2] In some species of insect, drawing blood meals is a behavior not normally witnessed that could be brought on by a sudden lack of avoidance of vertebrate odor.
The fruit-piercing moth (Calyptrata thalictri) has been known to draw blood from mammalian hosts when the number of a particular group of olfactory sensing neurons that generally produce a repellent response to vertebrate volatiles is reduced.