The difference between mimicry and deception

Mimicry and deception in plants can be attributed to a range of traits and behaviors, which are very diverse across all species. Depczynski and Gagliano (2013) define forms of deception as having an increased evolutionary fitness through gaining a benefit, and or avoiding a loss. An example of deception is a flower that tricks pollinators into thinking it has nectar; the flower is essentially pollinated for free. The orchid (Eulophia speciosa) pictured below demonstrates features that pollinators commonly associate with rewards, such as nectar. Scent, colour, shape and petal patterns can all contribute to persuading a pollinator into the flower, by convincing them that a reward lies within.

Adapted from Peter and Johnson 2013

Depczynski and Gagliano (2013) also describe mimicry as a form of deception whereby a species models its traits, behavior or appearance on another successful species. Mimicry is demonstrated in the image below, with species (b) a nectar bearing iris (Watsonia lepida), and species (a) a mimicking orchid (Disa pulchra). The iris is known by pollinators to produce nectar, hence they associate its appearance with a reward and visit it frequently. The orchid however, does not produce nectar, and instead tricks the pollinators into visiting by pretending to be an iris. 

Adapted from Jersakova et al. 2012

Although reward producing species have a much higher pollination rate than the deceptive species, they exhibit a much higher species diversity. Many deceptive species have both male and female reproductive parts and run the risk of self pollination, an issue that the species seem to have overcome. Peter and Johnson (2013) have theorized that once a pollinator has been fooled by a deceptive species, it leaves the plant and moves onto another, thereby eliminating the risk of self pollination.