Pollination systems involving floral mimicry of fruit: aspects of their ecology and evolution

Abstract

Floral mimicry of nonfloral resources is found across many angiosperm families, with mimicry of varied models including carrion, dung, fungi, insects and fruit. These systems provide excellent models to investigate the role of visual and olfactory cues for the ecology and evolution of plant-animal interactions. Interestingly, floral mimicry of fruit is least documented in the literature, although ripe or rotting fruits play an important role as a food or brood site in many insect groups such as Diptera, Hymenoptera and Coleoptera, and frugivorous vertebrates such as bats and birds. In ecosystems where fruit represents a frequent, reliable resource (e.g. tropical forests), this form of floral mimicry could represent a common mimicry class with specialization possible along multiple axes such as fruit of different species, stages of ripeness and microbial colonization. In this review, we summarize current research on floral mimicry of fruit. We place this review in the context of floral mimicry of a broader spectrum of nonfloral resources, and we discuss conceptual frameworks of mimicry vs generalized food deception or pre-existing sensory bias. Finally, we briefly review the specificity and complexity of fruit-insect ecological interactions, and we summarize important considerations and questions for moving forward in this field.

Deceptive pollination of Calanthe by skippers that commonly act as nectar thieves

“…However, a considerable number of angiosperm species do not provide rewards for pollinators, and have instead developed deception mechanisms to entice insects to visit their flowers and complete pollination without receiving anything in return. This is known as deceptive pollination (Goodrich & Jurgens ). No‐reward pollination mechanisms have been recorded in at least 32 angiosperm families, including 7,500 species, 6,500 of which belong to Orchidaceae (Jersakova et al .…”

Mushroom attracts hornets for spore dispersal by a distinctive yeasty scent

“…Therefore, it is intriguing that social hornets are also attracted to the yeasty scent of P. nipponica. Although similar mimicry systems are relatively well documented among flowering plants (Goodrich and J€ urgens 2018), the present study, to the best of our knowledge, provides the first description of a non-yeast fungal species utilizing fermentationlike scent to attract spore-dispersing insects.…”

“…). Given the attractive nature of fermented scents (Goodrich and Jürgens ), it is also possible that non‐yeast fungi also utilize olfactory signals by producing fermentation‐like scents that attract potential spore dispersers.…”

“…Furthermore, the scent of fermentation is so attractive to some insect species that several groups of flowering plants have independently evolved to produce yeasty scents that serve to facilitate pollination (Goodrich et al 2006, Goodrich and Raguso 2009, St€ okl et al 2010. Given the attractive nature of fermented scents (Goodrich and J€ urgens 2018), it is also possible that non-yeast fungi also utilize olfactory signals by producing fermentation-like scents that attract potential spore dispersers.…”

Flower scent of Ceropegia stenantha: electrophysiological activity and synthesis of novel components

“…Thereby, pollinators are fooled by visual, olfactory, or tactile signals which generate a sensory impression of a desired object they will, however, not find in the flowers. In specialized deceptive pollination systems, olfactory signals (i.e., floral scents) are considered most important for pollinator attraction (Vereecken and McNeil 2010; Johnson and Schiestl 2016; Goodrich and Jürgens 2018; Wee et al 2018); though additional traits, such as morphological or tactile cues, help to keep the disappointed pollinators interested, and trapping devices may even detain them in the flowers to achieve successful pollination (see Araceae: Chartier et al 2014; Apocynaceae-Asclepiadoideae: Vogel 1961; Heiduk et al 2017; Aristolochiaceae: Oelschlägel et al 2009, 2015; Orchidaceae: Singer 2002).…”