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1.
Adv Parasitol ; 124: 57-89, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38754927

RESUMO

For over a century, vector ecology has been a mainstay of vector-borne disease control. Much of this research has focused on the sensory ecology of blood-feeding arthropods (black flies, mosquitoes, ticks, etc.) with terrestrial vertebrate hosts. Of particular interest are the cues and sensory systems that drive host seeking and host feeding behaviours as they are critical for a vector to locate and feed from a host. An important yet overlooked component of arthropod vector ecology are the phenotypic changes observed in infected vectors that increase disease transmission. While our fundamental understanding of sensory mechanisms in disease vectors has drastically increased due to recent advances in genome engineering, for example, the advent of CRISPR-Cas9, and high-throughput "big data" approaches (genomics, proteomics, transcriptomics, etc.), we still do not know if and how parasites manipulate vector behaviour. Here, we review the latest research on arthropod vector sensory systems and propose key mechanisms that disease agents may alter to increase transmission.


Assuntos
Vetores Artrópodes , Animais , Vetores Artrópodes/fisiologia , Humanos , Artrópodes/fisiologia , Doenças Transmitidas por Vetores/transmissão , Doenças Transmitidas por Vetores/prevenção & controle , Interações Hospedeiro-Parasita
2.
Commun Biol ; 7(1): 552, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38720028

RESUMO

Global biodiversity gradients are generally expected to reflect greater species replacement closer to the equator. However, empirical validation of global biodiversity gradients largely relies on vertebrates, plants, and other less diverse taxa. Here we assess the temporal and spatial dynamics of global arthropod biodiversity dynamics using a beta-diversity framework. Sampling includes 129 sampling sites whereby malaise traps are deployed to monitor temporal changes in arthropod communities. Overall, we encountered more than 150,000 unique barcode index numbers (BINs) (i.e. species proxies). We assess between site differences in community diversity using beta-diversity and the partitioned components of species replacement and richness difference. Global total beta-diversity (dissimilarity) increases with decreasing latitude, greater spatial distance and greater temporal distance. Species replacement and richness difference patterns vary across biogeographic regions. Our findings support long-standing, general expectations of global biodiversity patterns. However, we also show that the underlying processes driving patterns may be regionally linked.


Assuntos
Artrópodes , Biodiversidade , Animais , Artrópodes/classificação , Artrópodes/fisiologia , Geografia , Análise Espaço-Temporal
3.
Ecol Lett ; 27(5): e14427, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38698677

RESUMO

Tree diversity can promote both predator abundance and diversity. However, whether this translates into increased predation and top-down control of herbivores across predator taxonomic groups and contrasting environmental conditions remains unresolved. We used a global network of tree diversity experiments (TreeDivNet) spread across three continents and three biomes to test the effects of tree species richness on predation across varying climatic conditions of temperature and precipitation. We recorded bird and arthropod predation attempts on plasticine caterpillars in monocultures and tree species mixtures. Both tree species richness and temperature increased predation by birds but not by arthropods. Furthermore, the effects of tree species richness on predation were consistent across the studied climatic gradient. Our findings provide evidence that tree diversity strengthens top-down control of insect herbivores by birds, underscoring the need to implement conservation strategies that safeguard tree diversity to sustain ecosystem services provided by natural enemies in forests.


Assuntos
Artrópodes , Biodiversidade , Aves , Clima , Comportamento Predatório , Árvores , Animais , Artrópodes/fisiologia , Aves/fisiologia , Cadeia Alimentar , Larva/fisiologia
4.
Ecol Lett ; 27(5): e14428, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685715

RESUMO

Species interact in different ways, including competition, facilitation and predation. These interactions can be non-linear or higher order and may depend on time or species densities. Although these higher-order interactions are virtually ubiquitous, they remain poorly understood, as they are challenging both theoretically and empirically. We propose to adapt niche and fitness differences from modern coexistence theory and apply them to species interactions over time. As such, they may not merely inform about coexistence, but provide a deeper understanding of how species interactions change. Here, we investigated how the exploitation of a biotic resource (plant) by phytophagous arthropods affects their interactions. We performed monoculture and competition experiments to fit a generalized additive mixed model to the empirical data, which allowed us to calculate niche and fitness differences. We found that species switch between different types of interactions over time, including intra- and interspecific facilitation, and strong and weak competition.


Assuntos
Ecossistema , Animais , Artrópodes/fisiologia , Modelos Biológicos , Plantas , Fatores de Tempo , Herbivoria , Comportamento Competitivo , Aptidão Genética
5.
J Anim Ecol ; 93(5): 540-553, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38509643

RESUMO

Understanding how anthropogenic activities induce changes in the functional traits of arthropod communities is critical to assessing their ecological consequences. However, we largely lack comprehensive assessments of the long-term impact of global-change drivers on the trait composition of arthropod communities across a large number of species and sites. This knowledge gap critically hampers our ability to predict human-driven impacts on communities and ecosystems. Here, we use a dataset of 1.73 million individuals from 877 species to study how four functionally important traits of carabid beetles and spiders (i.e. body size, duration of activity period, tolerance to drought, and dispersal capacity) have changed at the community level across ~40 years in different types of land use and as a consequence of land use changes (that is, urbanisation and loss of woody vegetation) at the landscape scale in Switzerland. The results show that the mean body size in carabid communities declined in all types of land use, with particularly stronger declines in croplands compared to forests. Furthermore, the length of the activity period and the tolerance to drought of spider communities decreased in most land use types. The average body size of carabid communities in landscapes with increased urbanisation in the last ~40 years tended to decrease. However, the length of the activity period, the tolerance to drought, and the dispersal capacity did not change significantly. Furthermore, urbanisation promoted increases in the average dispersal capacities of spider communities. Additionally, urbanisation favoured spider communities with larger body sizes and longer activity periods. The loss of woody areas at the landscape level was associated with trait shifts to carabid communities with larger body sizes, shorter activity periods, higher drought tolerances and strongly decreased dispersal capacities. Decreases in activity periods and dispersal capacities were also found in spider communities. Our study demonstrates that human-induced changes in land use alter key functional traits of carabid and spider communities in the long term. The detected trait shifts in arthropod communities likely have important consequences for their functional roles in ecosystems.


Assuntos
Aranhas , Animais , Aranhas/fisiologia , Suíça , Besouros/fisiologia , Tamanho Corporal , Urbanização , Ecossistema , Secas , Artrópodes/fisiologia , Florestas
6.
J Exp Zool A Ecol Integr Physiol ; 341(4): 357-363, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38318929

RESUMO

The extreme low humidity and temperatures in Antarctica make it one of the harsher areas for life on our planet. In a global change context, environmental barriers that prevented the arrival of alien species in Antarctica are weakening. Deception Island, one of the four active volcanoes of Antarctica, is especially vulnerable to the impacts of alien species. Geothermal areas (GA) in this Island offer unique microclimatic conditions that could differentially affect native and alien soil arthropods. Here we explore the desiccation tolerance of a native (Cryptopygus antarcticus) and an alien (Proisotoma minuta) springtail (Collembola) species to these extreme environmental conditions. GA and non-geothermal areas (NGA) were selected to evaluate intra- and interspecific variation in desiccation tolerance. Populations of P. minuta from GA had greater desiccation tolerance than populations from NGA. However, desiccation tolerance of C. antarcticus did not differ between GA and NGA. This native species had greater desiccation tolerance than the alien P. minuta, but also greater body size. Our findings show that the alien P. minuta responds differently to environmental conditions than the native C. antarcticus. Furthermore, body size may influence desiccation tolerance in these two springtail species.


Assuntos
Artrópodes , Dessecação , Animais , Regiões Antárticas , Artrópodes/fisiologia , Temperatura
7.
Sci Rep ; 14(1): 390, 2024 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172148

RESUMO

Our world is becoming increasingly urbanized with a growing human population concentrated around cities. The expansion of urban areas has important consequences for biodiversity, yet the abiotic drivers of biodiversity in urban ecosystems have not been well characterized for the most diverse group of animals on the planet, arthropods. Given their great diversity, comparatively small home ranges, and ability to disperse, arthropods make an excellent model for studying which factors can most accurately predict urban biodiversity. We assessed the effects of (i) topography (distance to natural areas and to ocean) (ii) abiotic factors (mean annual temperature and diurnal range), and (iii) anthropogenic drivers (land value and amount of impervious surface) on the occurrence of six arthropod groups represented in Malaise trap collections run by the BioSCAN project across the Greater Los Angeles Area. We found striking heterogeneity in responses to all factors both within and between taxonomic groups. Diurnal temperature range had a consistently negative effect on occupancy but this effect was only significant in Phoridae. Anthropogenic drivers had mixed though mostly insignificant effects, as some groups and species were most diverse in highly urbanized areas, while other groups showed suppressed diversity. Only Phoridae was significantly affected by land value, where most species were more likely to occur in areas with lower land value. Los Angeles can support high regional arthropod diversity, but spatial community composition is highly dependent on the taxonomic group.


Assuntos
Artrópodes , Dípteros , Animais , Humanos , Artrópodes/fisiologia , Ecossistema , Biodiversidade , Cidades , Los Angeles
8.
J Hazard Mater ; 466: 133574, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38280316

RESUMO

The environmental persistence of microplastics (MPs) is ubiquitous and problematic. Despite an increase in research on the soil ecotoxicity of MPs, the response of springtails to MP pollution remains unexplored. We hypothesized that MPs promote the accumulation of negative soil fungal groups and cause multigenerational effects in springtails. We performed a multigenerational study of high-density polyethylene MPs using springtail Folsomia candida and analyzed the soil fungal community. We found that soil entomopathogenic fungi and negative soil fungal groups accumulated in springtail F. candida due to soil MP pollution; subsequently, MPs negatively affected F. candida in the F2 generation. To the best of our knowledge, this is the first study to investigate the correlations between MP pollution, soil fungi, and fungi-feeding springtails. The study provides evidence of the accumulation of soil entomopathogenic fungi and negative soil fungal groups in F. candida caused by soil MP pollution.


Assuntos
Artrópodes , Microplásticos , Animais , Plásticos , Artrópodes/fisiologia , Poluição Ambiental , Solo
9.
Nature ; 622(7983): 545-551, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37758946

RESUMO

Trilobites are among the most iconic of fossils and formed a prominent component of marine ecosystems during most of their 270-million-year-long history from the early Cambrian period to the end Permian period1. More than 20,000 species have been described to date, with presumed lifestyles ranging from infaunal burrowing to a planktonic life in the water column2. Inferred trophic roles range from detritivores to predators, but all are based on indirect evidence such as body and gut morphology, modes of preservation and attributed feeding traces; no trilobite specimen with internal gut contents has been described3,4. Here we present the complete and fully itemized gut contents of an Ordovician trilobite, Bohemolichas incola, preserved three-dimensionally in a siliceous nodule and visualized by synchrotron microtomography. The tightly packed, almost continuous gut fill comprises partly fragmented calcareous shells indicating high feeding intensity. The lack of dissolution of the shells implies a neutral or alkaline environment along the entire length of the intestine supporting digestive enzymes comparable to those in modern crustaceans or chelicerates. Scavengers burrowing into the trilobite carcase targeted soft tissues below the glabella but avoided the gut, suggesting noxious conditions and possibly ongoing enzymatic activity.


Assuntos
Artrópodes , Fósseis , Intestinos , Animais , Artrópodes/anatomia & histologia , Artrópodes/enzimologia , Artrópodes/fisiologia , Evolução Biológica , Crustáceos/enzimologia , Síncrotrons , Concentração de Íons de Hidrogênio , Intestinos/química , Intestinos/enzimologia , Intestinos/metabolismo , Organismos Aquáticos/enzimologia , Organismos Aquáticos/fisiologia
10.
Vet Pathol ; 60(5): 678-688, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37401611

RESUMO

Histopathologic data of millipedes are scarce. Little is known about health and disease of these invertebrates despite their exhibition at zoological institutions and use in ecotoxicological studies. In a retrospective study of 69 zoo-housed giant African millipedes (Archispirostreptus gigas) submitted between 2018 and 2021, most deaths occurred during midwinter and in 2021. The most common lesion was inflammation (n = 55; 80%). Necrosis was seen concurrently in 31 (45%) millipedes and of these, bacteria (20; 29%) and fungi (7; 10%) were detected in lesions. Inflammation was seen in the head/collum (20; 29%), hemocoel (16; 23%), and appendages (9; 13%), specifically in perivisceral fat body (42; 61%), gut (16; 23%), tracheae (26; 38%), skeletal muscle (24; 35%), and ventral nerve (17; 25%). Inflammatory cell types and patterns included agranular hemocytes (61; 88%), granular hemocytes (39; 57%), and nodulation/encapsulation (47; 68%) often accompanied by melanization. The oral cavity or gut (ingestion), spiracles (inhalation), or cuticular defects were considered plausible routes of bacterial entry. Metazoan parasites (adult nematodes: 2, 3%; trematode ova: 2, 3%; and arthropods: 1, 1%) were associated with gut necrosis and inflammation in 5 millipedes. In addition, adult nematodes were noted in the gut of 4 millipedes without lesions. Neoplasia was not detected in any millipedes. Speculatively, environmental factors may have predisposed to disease, as most deaths occurred during winter months. Disease surveillance of millipedes is critical to optimize husbandry practices in zoo populations and investigate potential impacts of environmental degradation and climate change on wild millipedes.


Assuntos
Artrópodes , Animais , Estudos Retrospectivos , Artrópodes/fisiologia , Necrose/veterinária
11.
Integr Comp Biol ; 63(3): 530-547, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37429615

RESUMO

Understanding the biology of blood-feeding arthropods is critical to managing them as vectors of etiological agents. Circadian rhythms act in the regulation of behavioral and physiological aspects such as blood feeding, immunity, and reproduction. However, the impact of sleep on these processes has been largely ignored in blood-feeding arthropods, but recent studies in mosquitoes show that sleep-like states directly impact host landing and blood feeding. Our focus in this review is on discussing the relationship between sleep and circadian rhythms in blood-feeding arthropods along with how unique aspects such as blood gluttony and dormancy can impact sleep-like states. We highlight that sleep-like states are likely to have profound impacts on vector-host interactions but will vary between lineages even though few direct studies have been conducted. A myriad of factors, such as artificial light, could directly impact the time and levels of sleep in blood-feeding arthropods and their roles as vectors. Lastly, we discuss underlying factors that make sleep studies in blood-feeding arthropods difficult and how these can be bypassed. As sleep is a critical factor in the fitness of animal systems, a lack of focus on sleep in blood-feeding arthropods represents a significant oversight in understanding their behavior and its role in pathogen transmission.


Assuntos
Artrópodes , Condicionamento Físico Animal , Animais , Artrópodes/fisiologia , Sono , Ritmo Circadiano/fisiologia , Biologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-37198448

RESUMO

The neural basis underlying spatial orientation in arthropods, in particular insects, has received considerable interest in recent years. This special issue of the Journal of Comparative Physiology A seeks to take account of these developments by presenting a collection of eight review articles and eight original research articles highlighting hotspots of research on spatial orientation in arthropods ranging from flies to spiders and the underlying neural circuits. The contributions impressively illustrate the wide range of tools available to arthropods extending from specific sensory channels to highly sophisticated neural computations for mastering complex navigational challenges.


Assuntos
Artrópodes , Aranhas , Animais , Artrópodes/fisiologia , Orientação Espacial , Percepção Espacial , Insetos/fisiologia
13.
Glob Chang Biol ; 29(14): 4161-4173, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37114471

RESUMO

Anthropogenic increases in nitrogen (N) concentrations in the environment are affecting plant diversity and ecosystems worldwide, but relatively little is known about N impacts on terrestrial invertebrate communities. Here, we performed an exploratory meta-analysis of 4365 observations from 126 publications reporting on the richness (number of taxa) or abundance (number of individuals per taxon) of terrestrial arthropods or nematodes in relation to N addition. We found that the response of invertebrates to N enrichment is highly dependent on both species' traits and local climate. The abundance of arthropods with incomplete metamorphosis, including agricultural pest species, increased in response to N enrichment. In contrast, arthropods exhibiting complete or no metamorphosis, including pollinators and detritivores, showed a declining abundance trend with increasing N enrichment, particularly in warmer climates. These contrasting and context-dependent responses may explain why we detected no overall response of arthropod richness. For nematodes, the abundance response to N enrichment was dependent on mean annual precipitation and varied between feeding guilds. We found a declining trend in abundance with N enrichment in dry areas and an increasing trend in wet areas, with slopes differing between feeding guilds. For example, at mean levels of precipitation, bacterivore abundance showed a positive trend in response to N addition while fungivore abundance declined. We further observed an overall decline in nematode richness with N addition. These N-induced changes in invertebrate communities could have negative consequences for various ecosystem functions and services, including those contributing to human food production.


El aumento de las concentraciones de nitrógeno en el medio ambiente de forma antropogénica está afectando a la diversidad vegetal y a los ecosistemas de todo el mundo, pero aún se sabe relativamente poco sobre su impacto en comunidades de invertebrados terrestres. En este trabajo realizamos modelos meta-analíticos para explorar el efecto del enriquecimiento de nitrógeno en comunidades de invertebrados terrestres a escala global. Para ello, utilizamos una base de datos proveniente de 4.365 observaciones pareadas correspondientes a 126 publicaciones que estudiaron el efecto del enriquecimiento de nitrógeno en la riqueza (número de taxones) y/o abundancia (número de individuos por taxón) de artrópodos y/o nematodos. Encontramos que la respuesta de los invertebrados al enriquecimiento de nitrógeno depende en gran medida tanto de los rasgos de las especies como del clima local. La abundancia de artrópodos con metamorfosis incompleta, incluyendo especies que pueden crear plagas agrícolas, aumentó en respuesta al enriquecimiento de nitrógeno. Por el contrario, los artrópodos con metamorfosis completa o nula, incluidos polinizadores y detritívoros, mostraron una tendencia negativa de su abundancia con respecto al aumento de nitrógeno, especialmente en climas más cálidos. Además, no detectamos una respuesta general de la riqueza de artrópodos posiblemente por la variabilidad en respuestas observadas, tanto negativas como positivas. En el caso de los nematodos, la respuesta de sus abundancias al enriquecimiento de nitrógeno fue dependiente de la precipitación media anual y de su grupo trófico. En general, observamos una respuesta negativa de la abundancia de nematodos al enriquecimiento de nitrógeno en zonas secas y una tendencia positiva en zonas más húmedas, pero además los diferentes grupos tróficos estudiados presentaron diferentes respuestas. Por ejemplo, la abundancia de bacterívoros mostró una tendencia positiva en respuesta al enriquecimiento de nitrógeno bajo niveles medios de precipitación, mientras que la abundancia de fungívoros disminuyó. Además, observamos un descenso general de la riqueza de nematodos con más enriquecimiento de nitrógeno. Estos cambios inducidos por el nitrógeno en las comunidades de invertebrados podrían tener consecuencias negativas para diversas funciones y servicios de los ecosistemas, incluyendo aquellos que contribuyen a la producción de alimentos.


Assuntos
Artrópodes , Ecossistema , Humanos , Animais , Nitrogênio/farmacologia , Invertebrados/fisiologia , Artrópodes/fisiologia , Plantas
14.
Oecologia ; 201(3): 813-825, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36869183

RESUMO

Arthropods respond to vegetation in multiple ways since plants provide habitat and food resources and indicate local abiotic conditions. However, the relative importance of these factors for arthropod assemblages is less well understood. We aimed to disentangle the effects of plant species composition and environmental drivers on arthropod taxonomic composition and to assess which aspects of vegetation contribute to the relationships between plant and arthropod assemblages. In a multi-scale field study in Southern Germany, we sampled vascular plants and terrestrial arthropods in typical habitats of temperate landscapes. We compared independent and shared effects of vegetation and abiotic predictors on arthropod composition distinguishing between four large orders (Lepidoptera, Coleoptera, Hymenoptera, Diptera), and five functional groups (herbivores, pollinators, predators, parasitoids, detritivores). Across all investigated groups, plant species composition explained the major fraction of variation in arthropod composition, while land-cover composition was another important predictor. Moreover, the local habitat conditions depicted by the indicator values of the plant communities were more important for arthropod composition than trophic relationships between certain plant and arthropod species. Among trophic groups, predators showed the strongest response to plant species composition, while responses of herbivores and pollinators were stronger than those of parasitoids and detritivores. Our results highlight the relevance of plant community composition for terrestrial arthropod assemblages across multiple taxa and trophic levels and emphasize the value of plants as a proxy for characterizing habitat conditions that are hardly accessible to direct environmental measurements.


Assuntos
Artrópodes , Besouros , Animais , Artrópodes/fisiologia , Biodiversidade , Ecossistema , Herbivoria , Plantas
15.
Front Immunol ; 14: 1061899, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817439

RESUMO

Haematophagous arthropods can harbor various pathogens including viruses, bacteria, protozoa, and nematodes. Insects possess an innate immune system comprising of both cellular and humoral components to fight against various infections. Haemocytes, the cellular components of haemolymph, are central to the insect immune system as their primary functions include phagocytosis, encapsulation, coagulation, detoxification, and storage and distribution of nutritive materials. Plasmatocytes and granulocytes are also involved in cellular defense responses. Blood-feeding arthropods, such as mosquitoes and ticks, can harbour a variety of viral pathogens that can cause infectious diseases in both human and animal hosts. Therefore, it is imperative to study the virus-vector-host relationships since arthropod vectors are important constituents of the ecosystem. Regardless of the complex immune response of these arthropod vectors, the viruses usually manage to survive and are transmitted to the eventual host. A multidisciplinary approach utilizing novel and strategic interventions is required to control ectoparasite infestations and block vector-borne transmission of viral pathogens to humans and animals. In this review, we discuss the arthropod immune response to viral infections with a primary focus on the innate immune responses of ticks and mosquitoes. We aim to summarize critically the vector immune system and their infection transmission strategies to mammalian hosts to foster debate that could help in developing new therapeutic strategies to protect human and animal hosts against arthropod-borne viral infections.


Assuntos
Artrópodes , Culicidae , Carrapatos , Viroses , Animais , Humanos , Ecossistema , Mosquitos Vetores , Vetores Artrópodes , Artrópodes/fisiologia , Interações Hospedeiro-Patógeno , Mamíferos
16.
Artigo em Inglês | MEDLINE | ID: mdl-36813948

RESUMO

Representatives of arthropods, the largest animal phylum, occupy terrestrial, aquatic, arboreal, and subterranean niches. Their evolutionary success depends on specific morphological and biomechanical adaptations related to their materials and structures. Biologists and engineers have become increasingly interested in exploring these natural solutions to understand relationships between structures, materials, and their functions in living organisms. The aim of this special issue is to present the state-of-the-art research in this interdisciplinary field using modern methodology, such as imaging techniques, mechanical testing, movement capture, and numerical modeling. It contains nine original research reports covering diverse topics, including flight, locomotion, and attachment of the arthropods. The research achievements are essential not only to understand ecological adaptations, and evolutionary and behavioral traits, but also to drive prominent advances for engineering from exploitation of numerous biomimetic ideas.


Assuntos
Artrópodes , Animais , Artrópodes/fisiologia , Fenômenos Biomecânicos/fisiologia , Locomoção/fisiologia , Evolução Biológica , Aclimatação
17.
Bioessays ; 45(3): e2200167, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36693795

RESUMO

Paleoneuranatomy is an emerging subfield of paleontological research with great potential for the study of evolution. However, the interpretation of fossilized nervous tissues is a difficult task and presently lacks a rigorous methodology. We critically review here cases of neural tissue preservation reported in Cambrian arthropods, following a set of fundamental paleontological criteria for their recognition. These criteria are based on a variety of taphonomic parameters and account for morphoanatomical complexity. Application of these criteria shows that firm evidence for fossilized nervous tissues is less abundant and detailed than previously reported, and we synthesize here evidence that has stronger support. We argue that the vascular system, and in particular its lacunae, may be central to the understanding of many of the fossilized peri-intestinal features known across Cambrian arthropods. In conclusion, our results suggest the need for caution in the interpretation of evidence for fossilized neural tissue, which will increase the accuracy of evolutionary scenarios. Also see the video abstract here: https://youtu.be/2_JlQepRTb0.


Assuntos
Artrópodes , Tecido Nervoso , Animais , Evolução Biológica , Fósseis , Artrópodes/anatomia & histologia , Artrópodes/fisiologia , Paleontologia
18.
J Theor Biol ; 558: 111357, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36410450

RESUMO

The recent discovery that some terrestrial arthropods can detect, use, and learn from weak electrical fields adds a new dimension to our understanding of how organisms explore and interact with their environments. For bees and spiders, the filiform mechanosensory systems enable this novel sensory modality by carrying electric charge and deflecting in response to electrical fields. This mode of information acquisition opens avenues for previously unrealised sensory dynamics and capabilities. In this paper, we study one such potential: the possibility for an arthropod to locate electrically charged objects. We begin by illustrating how electrostatic interactions between hairs and surrounding electrical fields enable the process of location detection. After which we examine three scenarios: (1) the determination of the location and magnitude of multiple point charges through a single observation, (2) the learning of electrical and mechanical sensor properties and the characteristics of an electrical field through several observations, (3) the possibility that an observer can infer their location and orientation in a fixed and known electrical field (akin to "stellar navigation"). To conclude, we discuss the potential of electroreception to endow an animal with thus far unappreciated sensory capabilities, such as the mapping of electrical environments. Electroreception by terrestrial arthropods offers a renewed understanding of the sensory processes carried out by filiform hairs, adding to aero-acoustic sensing and opening up the possibility of new emergent collective dynamics and information acquisition by distributed hair sensors.


Assuntos
Artrópodes , Aranhas , Abelhas , Animais , Artrópodes/fisiologia , Aranhas/fisiologia , Eletricidade , Cabelo/fisiologia
19.
Proc Natl Acad Sci U S A ; 119(46): e2211283119, 2022 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-36343251

RESUMO

Springtails (Collembola) have been traditionally portrayed as explosive jumpers with incipient directional takeoff and uncontrolled landing. However, for these collembolans that live near the water, such skills are crucial for evading a host of voracious aquatic and terrestrial predators. We discover that semiaquatic springtails, Isotomurus retardatus, can perform directional jumps, rapid aerial righting, and near-perfect landing on the water surface. They achieve these locomotive controls by adjusting their body attitude and impulse during takeoff, deforming their body in midair, and exploiting the hydrophilicity of their ventral tube, known as the collophore. Experiments and mathematical modeling indicate that directional-impulse control during takeoff is driven by the collophore's adhesion force, the body angle, and the stroke duration produced by their jumping organ, the furcula. In midair, springtails curve their bodies to form a U-shape pose, which leverages aerodynamic forces to right themselves in less than ~20 ms, the fastest ever measured in animals. A stable equilibrium is facilitated by the water adhered to the collophore. Aerial righting was confirmed by placing springtails in a vertical wind tunnel and through physical models. Due to these aerial responses, springtails land on their ventral side ~85% of the time while anchoring via the collophore on the water surface to avoid bouncing. We validated the springtail biophysical principles in a bioinspired jumping robot that reduces in-flight rotation and lands upright ~75% of the time. Thus, contrary to common belief, these wingless hexapods can jump, skydive, and land with outstanding control that can be fundamental for survival.


Assuntos
Artrópodes , Animais , Artrópodes/fisiologia , Rotação , Água , Fenômenos Biomecânicos
20.
Sci Rep ; 12(1): 17273, 2022 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-36241676

RESUMO

Arthropod declines have been linked to agricultural intensification. However, information about the impacts of intensification is still limited for many crops, as is our understanding of the responses of different arthropod taxa and trophic groups, thus hindering the development of effective mitigation measures. We investigated the impacts of olive farming intensification on canopy-dwelling arthropods in the Mediterranean region. Intensification involves the increased use of agrochemicals, mechanisation and irrigation, but also structural changes from traditional orchards with low densities of large and old trees, to intensive and superintensive orchards with high to very high densities of smaller and younger trees, respectively. Canopy arthropods were vacuum-sampled at 53 sites representing the three orchard intensification levels, in spring, summer and autumn 2017. We evaluated how the arthropod community varied across intensification levels, and in response to orchard structure, management and landscape context. We found no changes in the diversity of arthropod taxa across intensification levels after correcting for sample coverage, but arthropod abundance declined markedly along the intensification gradient. Decreased abundance was associated with changes in orchard structure, lower herbaceous cover, and higher herbicide and insecticide use. The abundance of a specialized olive pest was lower in landscapes with higher woodland cover. The negative effects of intensification were stronger in spring and summer than in autumn, and parasitoids and predators were particularly affected. Overall, results suggest that retaining herbaceous cover, reducing agrochemical inputs and preserving natural woody elements in the landscape, may contribute to mitigate impacts of olive farming intensification on canopy arthropods, particularly on beneficial species.


Assuntos
Artrópodes , Herbicidas , Inseticidas , Olea , Agricultura/métodos , Animais , Artrópodes/fisiologia , Ecossistema , Florestas , Herbicidas/farmacologia , Inseticidas/farmacologia
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