Toward an insect evolution resolution Insects are the most diverse group of animals, with the largest number of species. However, many of the evolutionary relationships between insect species have been controversial and difficult to resolve. Misof et al. performed a phylogenomic analysis of protein-coding genes from all major insect orders and close relatives, resolving the placement of taxa. The authors used this resolved phylogenetic tree together with fossil analysis to date the origin of insects to ~479 million years ago and to resolve long-controversial subjects in insect phylogeny. Science, this issue p. 763 The phylogeny of all major insect lineages reveals how and when insects diversified. Insects are the most speciose group of animals, but the phylogenetic relationships of many major lineages remain unresolved. We inferred the phylogeny of insects from 1478 protein-coding genes. Phylogenomic analyses of nucleotide and amino acid sequences, with site-specific nucleotide or domain-specific amino acid substitution models, produced statistically robust and congruent results resolving previously controversial phylogenetic relations hips. We dated the origin of insects to the Early Ordovician [~479 million years ago (Ma)], of insect flight to the Early Devonian (~406 Ma), of major extant lineages to the Mississippian (~345 Ma), and the major diversification of holometabolous insects to the Early Cretaceous. Our phylogenomic study provides a comprehensive reliable scaffold for future comparative analyses of evolutionary innovations among insects.

Phylogenomics Resolves The Timing And Pattern Of Insect Evolution: Supplementary File Archives.

Most moths and butterflies of medical-veterinary importance are members of the following four superfamilies: Bombycoidea, Noctuoidea, Papilionoidea, and Zygaenoidea. At least 14 families, representing more than 100 species worldwide, have caterpillars (larvae) with stinging hairs or spines than can cause dermatitis (urticaria) upon contact with the skin. Adult moths also can pose health concerns by irritating eye tissues while feeding at night on tears (lachrymal secretions) of domestic and wild animals; feeding on fluids associated with open wounds; and in some cases actually piercing the skin with their proboscis to feed on blood. Air-borne wing scales of adults can cause inhalation allergies, in addition to the cocoon silk of certain moths causing silk-induced allergies. Among the more important veterinary problems are caterpillar-induced equine abortion and mare reproductive loss syndrome (equine amnionitis and fetal loss) following ingestion of certain species of caterpillars infesting pastures and browse areas.

18 – MOTHS AND BUTTERFLIES (Lepidoptera)

Nectarivorous insects generally adopt suction or lapping to extract nectar from flowers and it is believed that each species exhibits one specific feeding pattern. In recent literature, large groups of nectarivores are classified as either 'suction feeders', imbibing nectar through their proboscis, or 'lappers', using viscous dipping. Honeybees (Apis mellifera) are the well-known lappers by virtue of their hairy tongues. Surprisingly, we found that honeybees also employ active suction when feeding on nectar with low viscosity, defying their classification as lappers. Further experiments showed that suction yielded higher uptake rates when ingesting low-concentration nectar, while lapping resulted in faster uptake when ingesting nectar with higher sugar content. We found that the optimal concentration of suction mode in honeybees coincided with the one calculated for other typical suction feeders. Moreover, we found behavioural flexibility in the drinking mode: a bee is able to switch between lapping and suction when offered different nectar concentrations. Such volitional switching in bees can enhance their feeding capabilities, allowing them to efficiently exploit the variety of concentrations presented in floral nectars, enhancing their adaptability to a wide range of energy sources.

https://royalsocietypublishing.org/doi/pdf/10.1098/rsbl.2020.0449

Sucking or lapping: facultative feeding mechanisms in honeybees (Apis mellifera)

The mouthparts of most specialized fluid-feeding insects consist of more or less elongated components forming a proboscis. Functional types of mouthparts evolved as adaptations to particular food sources. Characteristic feeding techniques are used which are based on a combination of capillarity and a pressure gradient created by sucking pumps. Biting-sucking mandibles occur in some predaceous insect larvae and are used for extraoral digestion. Lapping mouthparts evolved in nectar-feeding insects; such proboscises are characterized by a loose food canal and setose, pro- and retractable structures at the tip which take up fluids mainly by capillarity. In contrast, piercing-sucking proboscises have pointed components to penetrate the host’s epidermis. The elongated components are firmly interlocked to form a tight food canal and a salivary duct. Piercing-sucking proboscises ingest fluid along a pressure gradient and occur in plant sap-sucking insects, blood feeders, and predaceous species. Sponging proboscises are rather short and retractable. Their soft and cushion-shaped apical components take up liquids from open fluid sources. Siphoning proboscises are particularly long and primarily adapted for nectar drinking. Such sucking mouthparts ingest fluid into the food canal predominantly by a pressure gradient.

Fluid-Feeding Mouthparts

The western honey bee, Apis mellifera L. (Hymenoptera), is arguably the most important pollinator worldwide. While feeding, A. mellifera uses a rapid back-and-forth motion with its brush-like mouthparts to probe pools and films of nectar. Because of the physical forces experienced by the mouthparts during the feeding process, we hypothesized that the mouthparts acquire wear or damage over time, which is paradoxical, because it is the older worker bees that are tasked with foraging for nectar and pollen. Here, we show that the average length of the setae (brush-like structures) on the glossa decreases with honey bee age, particularly when feeding on high-viscosity sucrose solutions. The nectar intake rate, however, remains nearly constant regardless of age or setae length (0.39±0.03 μg s−1 for honey bees fed a 45% sucrose solution and 0.48±0.05 μg s−1 for those fed a 35% sucrose solution). Observations of the feeding process with high-speed video recording revealed that the older honey bees with shorter setae dip nectar at a higher frequency. We propose a liquid transport model to calculate the nectar intake rate, energy intake rate and the power to overcome viscous drag. Theoretical analysis indicates that A. mellifera with shorter glossal setae can compensate both nectar and energy intake rates by increasing dipping frequency. The altered feeding behavior provides insight into how A. mellifera, and perhaps other insects with similar feeding mechanisms, can maintain a consistent fluid uptake rate, despite having damaged mouthparts.

/pdf/a-quick-tongue-older-honey-bees-dip-nectar-faster-to-g8lmvtrnbf.pdf

A quick tongue: older honey bees dip nectar faster to compensate for mouthpart structure deterioration.

Fluid-feeding insects, such as butterflies, moths and flies (20% of all animal species), are faced with the common selection pressure of having to remove and feed on trace amounts of fluids from porous surfaces. Insects able to acquire fluids that are confined to pores during drought conditions would have an adaptive advantage and increased fitness over other individuals. Here, we performed feeding trials using solutions with magnetic nanoparticles to show that butterflies and flies have mouthparts adapted to pull liquids from porous surfaces using capillary action as the governing principle. In addition, the ability to feed on the liquids collected from pores depends on a relationship between the diameter of the mouthpart conduits and substrate pore size diameter; insects with mouthpart conduit diameters larger than the pores cannot successfully feed, thus there is a limiting substrate pore size from which each species can acquire liquids for fluid uptake. Given that natural selection independently favoured mouthpart architectures that support these methods of fluid uptake (Diptera and Lepidoptera share a common ancestor 280 Ma that had chewing mouthparts), we suggest that the convergence of this mechanism advocates this as an optimal strategy for pulling trace amounts of fluids from porous surfaces.

https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2016.2026

Mouthpart conduit sizes of fluid-feeding insects determine the ability to feed from pores

Performance of hydrogel immobilized bioreactors combined with different iron ore wastes for denitrification and removal of copper and lead: Optimization and possible mechanism.

Newly isolated lysozyme-producing strain Proteus mirabilis sp. SJ25 reduced the waste activated sludge: Performance and mechanism.

Tea saponin enhanced bioleaching of Fusarium solani to remove hexavalent chromium from soil

Fluid-feeding insects ingest a variety of liquids, which are present in the environment as pools, films, or confined to small pores. Studies of liquid acquisition require assessing mouthpart structure and function relationships; however, fluid uptake mechanisms are historically inferred from observations of structural architecture, sometimes unaccompanied with experimental evidence. Here, we report a novel method for assessing fluid-uptake abilities with butterflies (Lepidoptera) and flies (Diptera) using small amounts of liquids. Insects are fed with a 20% sucrose solution mixed with fluorescent, magnetic nanoparticles from filter papers of specific pore sizes. The crop (internal structure used for storing fluids) is removed from the insect and placed on a confocal microscope. A magnet is waved by the crop to determine the presence of nanoparticles, which indicate if the insects are able to ingest fluids. This methodology is used to reveal a widespread feeding mechanism (capillary action and liquid bridge formation) that is potentially shared among Lepidoptera and Diptera when feeding from porous surfaces. In addition, this method can be used for studies of feeding mechanisms among a variety of fluid-feeding insects, including those important in disease transmission and biomimetics, and potentially other studies that involve nano- or micro-sized conduits where liquid transport requires verification.

Huan Yan

Papers

Mouthpart conduit sizes of fluid-feeding insects determine the ability to feed from pores

Performance of hydrogel immobilized bioreactors combined with different iron ore wastes for denitrification and removal of copper and lead: Optimization and possible mechanism.

Newly isolated lysozyme-producing strain Proteus mirabilis sp. SJ25 reduced the waste activated sludge: Performance and mechanism.

Tea saponin enhanced bioleaching of Fusarium solani to remove hexavalent chromium from soil

The Ingestion of Fluorescent, Magnetic Nanoparticles for Determining Fluid-uptake Abilities in Insects.