Spontaneous choices for insect-pollinated flower shapes by wild non-eusocial halictid bees

Abstract

The majority of angiosperms require animal pollination for reproduction and insects are the dominant group of animal pollinators. Bees are considered one of the most important and abundant insect pollinators. Research into bee behaviour and foraging decisions has typically centred on managed eusocial bee species, Apis mellifera and Bombus terrestris. Non-eusocial bees are understudied with respect to foraging strategies and decision-making, such as flower preferences. Understanding whether there are fundamental foraging strategies and preferences which are features of insect groups can provide key insights into the evolution of flower-pollinator co-evolution. In the current study, Lasioglossum (Chilalictus) lanarium and L. (Parasphecodes) sp., two native Australian generalist halictid bees, were tested for flower shape preferences between native insect-pollinated and bird-pollinated flowers. Each bee was presented with achromatic images of either insect-pollinated or bird-pollinated flowers in a circular arena. Both native bee species demonstrated a significant preference for images of insect-pollinated flowers. These preferences are similar to those found in A. mellifera, suggesting that flower shape preference may be a deep-rooted evolutionary occurrence within bees. With growing interest in the sensory capabilities of non-eusocial bees as alternative pollinators, the current study also provides a valuable framework for further behavioural testing of such species.

Ants are more than just curious bystanders to some flowers—they act as significant pollinators

“…Two interaction networks (or matrices) were created separately: (a) at the species level and (b) at the higher taxonomic level (family and subfamily). Data obtained from the network analysis were classified into two broad categories ( 1 ): plants’ exclusivity to ants—(i) the pollination of a single plant species by multiple ant species, (ii) the pollination of a limited number of plant species by multiple ant species, (iii) the pollination of a single plant species by limited species of ants, and (iv) the pollination of a single plant species by a single ant species—and ( 2 ) ants’ exclusivity to plants—(v) the pollination of multiple plant species by a single ant species, (vi) the pollination of a limited number of plant species by a single ant species, and (vii) the pollination of multiple plant species by multiple ant species.…”

“…Nature's beauty and grace are sleeping into the seed vessels, which is only possible through the diverse pollination strategies in plants and insects under self and crosspollination modes (1). A floral visitor's efficacy can be measured in terms of its contribution to plant health (2)(3)(4); similarly, the visitor's pollination performance is also correlated to its fitness (5).…”

Flower-visiting lizards as key ecological actors for an endemic and critically endangered plant in the Canary Islands

“…Therefore, although Lasioglossum spp. and other halictid bees have been reported as pollinators of other species (Singer & Cocucci 1999;Howard et al 2021), including some Fabaceae (Gros 2001), it seems unlikely that L. arctifrons was a quantitatively important pollinator of L. maculatus, though it may happen for flowers previously visited by lizards. Sometimes, after visits by lizards, flowers may be left with anthers and stigma exposed, then it may be possible that pollen grains carried by L. arctifrons to be transferred to a stigma.…”

Floral Trait Preferences of Three Common wild Bee Species

“…often dominate wild bee communities and their social behavior is well studied [ 18 , 19 ] but have been neglected in studies of floral cue preference (except the study series on Australian Lasioglossum sp. by Howard [ 20 , 21 , 22 ]). Alongside, Osmia bicornis bees, that are commercially used as pollinators of orchard trees and are well studied regarding their pollination efficiency [ 23 , 24 ], are also rarely tested for their floral cue preferences (but see, e.g., [ 25 , 26 ]).…”