Flower petal microtexture is a tactile cue for bees

Abstract

Honeybees are shown to be able to detect, learn, and discriminate between microsculptured epidermes of flower petals. The sensilla trichodea at the tips of the bees' antennae are in the same size range as the microsculptural features of the petals (ca. 10 ,um), which presumably deflect these mechanoreceptive sensilla in characteristic ways. Honeybees were trained to associate reward with one floral texture and to choose that over another. Further, the bees also recognized differences in textures at different ends of petals of the same species. The phenomenon is significant in that it suggests another way in which insect pollinators can discriminate between the flowers of different plant species and so act as species isolators. Also, the microsculptural patterns differ from one end of a petal to the other and, therefore, can be used as nectar-guides by foraging bees. This study presents a previously unreported conditioned response to texture by insects and shows the functional significance of a floral character used in plant taxonomy.

Tactile learning by a whip spider, Phrynus marginemaculatus C.L. Koch (Arachnida, Amblypygi)

“…The tactile properties of flower petals are used by Manduca sexta to locate nectar using its proboscis (Goyret and Raguso 2006) and can be learned by bees (Kevan and Lane 1985;Erber et al 1998). During goal orientation, the desert ant, Cataglyphis fortis (a predominantly visual navigator), can learn tactile properties of the ground .…”

Look and touch: multimodal sensory control of flower inspection movements in the nocturnal hawkmothManduca sexta

“…By contrast, the use of tactile floral guides (henceforth: tactile guides) is supported experimentally. Honeybees learn petal microtexture orientation, suggesting that they could use this flower feature as a tactile guide (Kevan and Lane, 1985). Moreover, the nocturnal hawkmoth Manduca sexta has been recently shown to inspect flowers using tactile input from their 9cm long proboscis (Goyret and Raguso, 2006).…”

Antennal motor activity induced by pilocarpine in the American cockroach

“…In fact, insects oscillate their antennae vigorously when they detect attractive odors such as sex pheromones (Rust et al 1976;Olberg 1983;Nishiyama et al 2007). Repetitive contacts of antennae may also occur when insects encounter obstacles or gaps (Pelletier and McLeod 1994;Dürr et al 2001;Watson et al 2002;Blaesing and Cruse 2004), conspecific mates (Loher and Rence 1978), physical objects to approach (Okada and Toh 2006), and tactile objects to discriminate (Martin 1965;Kevan and Lane 1985;Erber et al 1998). These behavioral observations clearly indicate that the insect antenna is a typical example of an active sensor.…”