Ligand-shell engineering of ultrasmall metal clusters is a burgeoning research field aiming to develop cluster-specific properties. However, predicting these properties prior synthesis challenging due their high sensitivity geometric and/or electronic variations in cores, hindering further exploration. In this study, we present theory-directed ligand-shell design and significant red-shift absorption prolate-shaped [Au8(diphosphine)4Cl2]2+ cluster by synthesizing characterizing enantiopure...

Summary The compound eyes of the Eastern Pale Clouded Yellow butterfly, Colias erate, contain three types ommatidia (I, II and III), identifiable by differing arrangements pigment clusters around rhabdoms. color is red in all ommatidial except for type females, where orange. Intracellular recordings demonstrated that spectral sensitivities proximal photoreceptors (R5-8) both sexes are strongly tuned perirhabdomal pigments. These pigments act as long-pass filters, shifting peak into...

Ants are thought to be special among Hymenopterans in having only dichromatic colour vision based on two spectrally distinct photoreceptors. Many ants highly visual animals, however, and use extensively for navigation. We show here that congeneric day- night-active Australian have three photoreceptor types, potentially supporting trichromatic vision. Electroretinogram recordings the presence of spectral sensitivities with peaks (λmax) at 370, 450 550 nm Myrmecia vindex 470 510 day-active...

Queens of social insects make all mate-choice decisions on a single day, except in honeybees whose queens can conduct mating flights for several days even when already inseminated by number drones. Honeybees therefore appear to have unique, evolutionarily derived form sexual conflict: queen’s decision pursue risky additional is driven later-life fitness gains from genetically more diverse worker-offspring but reduces paternity shares the drones she mated with. We used artificial...

Ligand-protected gold clusters with an asymmetric nature have emerged as a novel class of chiral compounds, but the origins their chiroptical activities associated helical charge movements in electronic transitions remain unexplored. Herein, we perform experimental and theoretical studies on structures properties Au

The ability to visualize small moving objects is vital for the survival of many animals, as these could represent predators or prey. For example, predatory insects, including dragonflies, robber flies and killer flies, perform elegant, high-speed pursuits both biological artificial targets. Many non-predatory male hoverflies blowflies, also pursue targets during territorial courtship interactions. To date, most hoverfly have been studied outdoors. investigate (Eristalis tenax) under more...

Vision is crucial for animals to find prey, locate conspecifics, and navigate within cluttered landscapes. Animals need discriminate objects against a visually noisy background. However, the ability detect spatial information limited by eye size. In insects, as individuals become smaller, space available eyes reduces, which affects number of ommatidia, size lens downstream processing capabilities. The evolution small body in lineage, known miniaturisation, common insects. Here, using pattern...

Visual systems play a vital role in guiding the behaviour of animals. Understanding visual information animals are able to acquire is therefore key understanding their visually mediated decision making. Compound eyes, dominant eye type arthropods, inherently low-resolution structures. Their ability resolve spatial detail depends on sampling resolution (interommatidial angle) and quality ommatidial optics. Current techniques for estimating interommatidial angles difficult, generally require...

The Green Weaver ants, Oecophylla smaragdina are iconic animals known for their extreme cooperative behaviour where they bridge gaps by linking to each other build living chains. They visually oriented animals, chains towards closer targets, use celestial compass cues navigation and visual predators. Here, we describe sensory capacity. major workers of O. have more ommatidia (804) in eye compared minor (508), but the facet diameters comparable between both castes. We measured impulse...

The eyes of most animals exhibit a trade-off between spatial resolving power and absolute sensitivity, which likely reflects functional adaptations for the animals' visual ecology. When operate in dim light conditions, sensitivity an eye needs to be increased because signal-noise ratio information is typically low, even though this potentially compromises power. Here, we investigated contrast two congeneric ant species: diurnal-crepuscular Myrmecia tarsata nocturnal midas using pattern...

In addition to compound eyes, honeybees (Apis mellifera) possess three single-lens eyes called ocelli located on the top of head. Ocelli are involved in head-attitude control and some insects have been shown provide celestial compass information. Anatomical early electrophysiological studies suggested that UV blue-green photoreceptors polarization sensitive. However, their retinal distribution receptor characteristics not documented. Here, we used intracellular electrophysiology determine...

Abstract In recent years, virtual reality arenas have become increasingly popular for quantifying visual behaviors. By using the actions of a constrained animal to control scenery, is provided perception moving through simulated environment. As in space, this allows detailed behavioral quantification. Additionally, as world generally computer-generated mechanistic quantification triggers behavior. We created novel arena combining machine vision with gaming engine Unity. For tethered flight,...

Abstract In recent years, virtual reality arenas have become increasingly popular for quantifying visual behaviours. By using the actions of a constrained animal to control scenery, perceives that it is moving through world. Importantly, as in space, behavioural quantification facilitated. Furthermore, computer‐generated scenery allows identification triggers behaviour. We created novel arena combining machine vision with gaming engine Unity. For tethered flight, we enhanced an existing...

Colour signals, and the ability to detect them, are important for many animals can be vital their survival fitness. Fiddler crabs use colour information recognise conspecifics, but vision capabilities remain unclear. Many studies have attempted measure spectral sensitivity identify contributing retinular cells, existing evidence is inconclusive. We used electroretinogram (ERG) measurements intracellular recordings from cells estimate of Gelasimus dampieri track diurnal changes in...

Nocturnal insects likely have evolved distinct physiological adaptations to enhance sensitivity for tasks, such as catching moving prey, where the signal-noise ratio of visual information is typically low. Using electroretinogram recordings, we measured impulse response and flicker fusion frequency (FFF) in six congeneric species Myrmecia ants with different diurnal rhythms. The FFF, which measures ability an eye respond a flickering light, significantly lower nocturnal (∼125 Hz) compared...

Many animals use motion vision information to control dynamic behaviors. Predatory animals, for example, show an exquisite ability detect rapidly moving prey, followed by pursuit and capture. Such target detection is not only used predators but also important in conspecific interactions, such as male hoverflies defending their territories against intruders. Visual believed be subserved specialized target-tuned neurons found a range of species, including vertebrates arthropods. However, how...

Abstract Responding rapidly to visual stimuli is fundamental for many animals. For example, predatory birds and insects alike have amazing target detection abilities, with incredibly short neural behavioral delays, enabling efficient prey capture. Similarly, looming objects need be avoided ensure immediate survival, as these could represent approaching predators. Male Eristalis tenax hoverflies are nonpredatory, highly territorial that perform high-speed pursuits of conspecifics other...

We investigated the stridulatory courtship initiated by male-male contact after agonistic encounters and effect of dominance status on subsequent reproductive behavior in cricket Gryllus bimaculatus. When two male crickets were kept together a small area, their was quickly established through fighting or non-fighting interactions. Approximately 10 min pairing, most dominant males produced calling and/or songs presence subordinate males. This appeared to be triggered some chemicals body...

Abstract Animals’ sensory systems enable them to navigate and interact with their environments. Adaptive specializations of these can generate novel structures or organs that support highly unique niche adaptations. We report the discovery a organ in group praying mantises (Insecta, Mantodea, Nanomantoidea), which have an unusual “leaf-planking” ecomorphic life strategy, laying against undersides broadleaf vegetation. Histology, scanning electron microscopy, x-ray computed tomography all...

Abstract Stingless bees engage in a range of visually guided behaviours that require relatively high spatial resolution and contrast sensitivity. Although the eyes honeybees, bumblebees, carpenter bees, sweat have been studied extensively, there is limited knowledge stingless bees. Here, we two sympatric Australian species, Tetragonula carbonaria Austroplebeia australis , which are important crop pollinators. The bigger A. had more larger ommatidial facets compared to T. . Using pattern...