Caterpillars and fungal pathogens: two co-occurring parasites of an ant-plant mutualism

In mutualisms, each interacting species obtains resources from its partner that it would obtain less efficiently if alone, and so derives a net fitness benefit. In exchange for shelter (domatia) and food, mutualistic plant-ants protect their host myrmecophytes from herbivores, encroaching vines and fungal pathogens. Although selective filters enable myrmecophytes to host those ant species most favorable to their fitness, some insects can by-pass these filters, exploiting the rewards supplied whilst providing nothing in return. This is the case in French Guiana for Cecropia obtusa (Cecropiaceae) as Pseudocabima guianalis caterpillars (Lepidoptera, Pyralidae) can colonize saplings before the installation of their mutualistic Azteca ants. The caterpillars shelter in the domatia and feed on food bodies (FBs) whose production increases as a result. They delay colonization by ants by weaving a silk shield above the youngest trichilium, where the FBs are produced, blocking access to them. This probable temporal priority effect also allows female moths to lay new eggs on trees that already shelter caterpillars, and so to occupy the niche longer and exploit Cecropia resources before colonization by ants. However, once incipient ant colonies are able to develop, they prevent further colonization by the caterpillars. Although no higher herbivory rates were noted, these caterpillars are ineffective in protecting their host trees from a pathogenic fungus, Fusarium moniliforme (Deuteromycetes), that develops on the trichilium in the absence of mutualistic ants. Therefore, the Cecropia treelets can be parasitized by two often overlooked species: the caterpillars that shelter in the domatia and feed on FBs, delaying colonization by mutualistic ants, and the fungal pathogen that develops on old trichilia. The cost of greater FB production plus the presence of the pathogenic fungus likely affect tree growth

‘New and important careers’: how women excelled at the BBC, 1923–1939

From its beginnings in 1923, the BBC employed a sizeable female workforce. The majority were in support roles as typists, secretaries and clerks but, during the 1920s and 1930s, a significant number held important posts. As a modern industry, the BBC took a largely progressive approach towards the ‘career women’ on its staff, many of whom were in jobs that were developed specifically for the new medium of broadcasting. Women worked as drama producers, advertising representatives and Children’s Hour Organisers. They were talent spotters, press officers and documentary makers. Three women attained Director status while others held significant administrative positions. This article considers in what ways it was the modernity and novelty of broadcasting, combined with changing employment possibilities and attitudes towards women evident after the First World War, that combined to create the conditions in which they could excel

Stridulations Reveal Cryptic Speciation in Neotropical Sympatric Ants

The taxonomic challenge posed by cryptic species underlines the importance of using multiple criteria in species delimitation. In the current paper we tested the use of acoustic analysis as a tool to assess the real diversity in a cryptic species complex of Neotropical ants. In order to understand the potential of acoustics and to improve consistency in the conclusions by comparing different approaches, phylogenetic relationships of all the morphs considered were assessed by the analysis of a fragment of the mitochondrial DNA cytochrome b. We observed that each of the cryptic morph studied presents a morphologically distinct stridulatory organ and that all sympatric morphs produce distinctive stridulations. This is the first evidence of such a degree of specialization in the acoustic organ and signals in ants, which suggests that stridulations may be among the cues used by these ants during inter-specific interactions. Mitochondrial DNA variation corroborated the acoustic differences observed, confirming acoustics as a helpful tool to determine cryptic species in this group of ants, and possibly in stridulating ants in general. Congruent morphological, acoustic and genetic results constitute sufficient evidence to propose each morph studied here as a valid new species, suggesting that P. apicalis is a complex of at least 6 to 9 species, even if they present different levels of divergence. Finally, our results highlight that ant stridulations may be much more informative than hitherto thought, as much for ant communication as for integrative taxonomists

It’s Not a Bug, It’s a Feature: Functional Materials in Insects

Over the course of their wildly successful proliferation across the earth, the insects as a taxon have evolved enviable adaptations to their diverse habitats, which include adhesives, locomotor systems, hydrophobic surfaces, and sensors and actuators that transduce mechanical, acoustic, optical, thermal, and chemical signals. Insect‐inspired designs currently appear in a range of contexts, including antireflective coatings, optical displays, and computing algorithms. However, as over one million distinct and highly specialized species of insects have colonized nearly all habitable regions on the planet, they still provide a largely untapped pool of unique problem‐solving strategies. With the intent of providing materials scientists and engineers with a muse for the next generation of bioinspired materials, here, a selection of some of the most spectacular adaptations that insects have evolved is assembled and organized by function. The insects presented display dazzling optical properties as a result of natural photonic crystals, precise hierarchical patterns that span length scales from nanometers to millimeters, and formidable defense mechanisms that deploy an arsenal of chemical weaponry. Successful mimicry of these adaptations may facilitate technological solutions to as wide a range of problems as they solve in the insects that originated them.Insects have evolved manifold optimized solutions to everyday problems. The diversity and precision of their hierarchical material adaptations often outsmart and outperform current man‐made approaches. These materials hence provide an excellent basis for the inspiration of new technological approaches by taking design cues from nature’s solutions.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143760/1/adma201705322.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143760/2/adma201705322_am.pd

Compound nesting of Strumigenys sp. (Myrmicinae) and Diacamma sp. (Ponerinae), and other nesting symbioses of myrmicine and ponerine ants in Southeast Asia

Kaufmann E, Malsch A, Erle M, Maschwitz U. Compound nesting of Strumigenys sp. (Myrmicinae) and Diacamma sp. (Ponerinae), and other nesting symbioses of myrmicine and ponerine ants in Southeast Asia. Insectes Sociaux. 2003;50(1):88-97

Pseudolasius spp. (Formicinae) and their trophobionts - Codispersal by colony budding

Kaufmann E, Malsch A, Williams DJ, Maschwitz U. Pseudolasius spp. (Formicinae) and their trophobionts - Codispersal by colony budding. Sociobiology . 2003;41(2):429-436.Biological data on three species of Pseudolasius (Formicinae) provide new circumstantial evidence on the codispersal of these ants with their trophobionts, in this case Tetraneura nigriabdominalts (Aphididae) and to a lesser extent, Paracoccus sp. (Pseudococcidae)

Ant-gardens on the giant bamboo gigantochloa scortechinii(Poaceae) in West-Malaysia

We report the first experimental evidence of seed collecting behavior in an ant-garden-inhabiting ant species in the Palaeotropics. Vascular epiphytes growing on the giant bamboo Gigantochloa scortechinii (Poaceae) were collected at Ulu Gombak, West Malaysia. Sixteen epiphyte species were growing in carton-nests of seven ant species. All epiphytes on bamboo were associated with ants. The most frequent ant species (Crematogaster sp. 1, Myrmicinae) apparently nests only on bamboo. It was tested for its behavior towards the seeds of three epiphyte species (Dischidia nummularia (Asclepiadaceae), Aeschynanthus fecundus, Aeschynanthus albidus (Gesneriaceae)) and one non-epiphyte species (Emilia sonchifolia (Asteraceae)). Most of the offered epiphytes' seeds were carried to the nest, while the seeds of the non-epiphyte were ignored or even discarded. There were no species-specific differences among the epiphytes' seeds. We hypothesize that seed-collecting behavior is necessary for the establishment of ant-garden associations and for the colonization of bamboo culms by epiphytes. The smooth-surfaced and relatively short-lived bamboo culms would not host epiphytes without the mediation of the ants. We suspect that ants may also have a great influence on the distribution of epiphytes on other hosts. In this paper we describe ants as active nest builders and seed collectors that give certain epiphytes the opportunity to live in open and sun exposed habitats on bamboo. Benefits to the ants are discussed as well