Anna Stöckl and Michael Harrap
Pollination: A Curious Case of Cross-Kingdom Cooperation

May 23, 2023

Anna Stöckl - More than just a pretty flower: how visual patterns guide insect–plant interactions.

We have all experienced the fascinating range of colourful patterns that flowers display on our windowsills and in our gardens – though while merely pleasing to us, they can be of great importance to animals that visit flowers for their daily food supply. Flower patterns are thought to lead insect pollinators to a plant’s nectary, expressed in the term ‘nectar guides’. I will present recent work on how flower patterns guide the flower interactions of two insect pollinators, the buff-tailed bumblebee (Bombus terrestris), and the hummingbird hawkmoths (Macroglossum stellatarum). These two species have very different flower-interaction strategies, as bumblebees land on the flowers and make their way to the nectary on foot, while hawkmoths hover in front of them and search for the nectary with their long proboscis. I will discuss how their different foraging strategies affect the use of flower patterns on the way to finding the nectary.

Anna Stöckl

Michael Harrap - Overlooked floral display traits and their influence on pollinator behaviour.

Floral displays are multimodal, simultaneously producing signals and cues through different sensory modes (such as visual, olfactory and tactile). Pollinators, particularly bees, respond to variation in these different modalities, showing innate and learned preferences based on differences in these floral display traits. Historically research has focused on pollinator responses to floral traits that are detectable to humans, such as visual and scent cues. This has caused other floral display traits, that may be detectable and used by pollinators to inform foraging but are imperceptible to humans without specialist equipment, to be overlooked. Such ‘overlooked’ floral traits include floral humidity and temperature. Here, I will discuss my work focused on such overlooked floral traits, testing their capacity to function as floral cues or signals. This will include my work sampling their diversity across flower species, and testing the capacity of free flying bumblebees (Bombus terrestris) to respond to variation in these floral traits comparable to that seen in nature.

Michael Harrap