Multispecies Assemblages Research Articles

Intransitivity in plant-soil feedbacks is rare but is associated with multispecies coexistence.

Although plant-soil feedback (PSF) is being recognized as an important driver of plant recruitment, our understanding of its role in species coexistence in natural communities remains limited by the scarcity of experimental studies on multispecies assemblages. Here, we experimentally estimated PSFs affecting seedling recruitment in 10 co-occurring Mediterranean woody species. We estimated weak but significant species-specific feedback. Pairwise PSFs impose similarly strong fitness differences and stabilizing-destabilizing forces, most often impeding species coexistence. Moreover, a model of community dynamics driven exclusively by PSFs suggests that few species would coexist stably, the largest assemblage with no more than six species. Thus, PSFs alone do not suffice to explain coexistence in the studied community. A topological analysis of all subcommunities in the interaction network shows that full intransitivity (with all species involved in an intransitive loop) would be rare but it would lead to species coexistence through either stable or cyclic dynamics.

Karyotypic stasis and swarming influenced the evolution of viral tolerance in a species-rich bat radiation

The emergence of COVID-19 and severe acute respiratory syndrome (SARS) has prioritized understanding bats' viral tolerance. Myotis bats are exceptionally species rich and have evolved viral tolerance. They also exhibit swarming, a cryptic behavior where large, multi-species assemblages gather for mating, which has been hypothesized to promote interspecific hybridization. To resolve the coevolution of genome architecture and their unusual antiviral tolerance, we undertook a phylogenomic analysis of 60 Old World Myotis genomes. We demonstrate an extensive history of introgressive hybridization that has replaced the species phylogeny across 17%-93% of the genome except for pericentromeric regions of macrochromosomes. Introgression tracts were enriched on microchromosome regions containing key antiviral pathway genes overexpressed during viral challenge experiments. Together, these results suggest that the unusual Myotis karyotype may have evolved to selectively position immune-related genes in high recombining genomic regions prone to introgression of divergent alleles, including a diversity of interleukin loci responsible for the release of pro-inflammatory cytokines.

Assortment of Dusky Salamanders along Moisture Gradients in Multispecies Assemblages: Revisiting the Ideas

Assortment of Dusky Salamanders along Moisture Gradients in Multispecies Assemblages: Revisiting the Ideas

Shit! Towards an experimental multiple-perspective approach to human-microbiome relations

ABSTRACTFor HCI to move beyond human exceptionalism requires embracing more-than-humans, humans as parts of ecosystems, as multispecies assemblages and events. In short, decentering the human. Yet, human experience sits at the center of HCI. We report from Shit!, an experimental research inquiry into the relationship between people suffering intestinal dysbiosis and their gut microbiome. We discuss a series of Shitty workshops and the method’s suitability for fostering multiple-perspectives on human-microbiome relations. We reflect on the possibilities and challenges of conducting intimate, more-than-human design inquiries through workshops: carefully curated tasks undertaken collaboratively, in social settings, with facilitation. Our contribution is threefold: (1) we trace the lineage of workshops in HCI and Participatory Design; (2) we highlight and problematize human-microbiome relationships in sensitive participatory health-care contexts; (3) we deepen understanding of how workshops – as method – may be rearticulated in more-than-human design processes. We propose future directions in the work to extend and supplement the efficacy of the workshop with self-experimentation kits. Rather than developing design research methods anew, we argue the necessity of inquiring into and experimenting with the workshop as an established design method in HCI to prompt a re-articulation of situated knowledges and allow multiple voices, perspectives, and species to flourish.

Human land-use changes the diets of sympatric native and invasive mammal species.

The consequences of biological invasions and habitat degradation for native biodiversity depend on how species cope with the individual and synergetic challenges these processes present. To assess the impact of anthropogenic land-use on the food web architecture of an invaded community, we examine the diets of nine native and two highly invasive mammal species at different trophic levels, inhabiting different land-uses across six biogeographic regions in Tasmania, Australia. We use two complementary methods, environmental DNA metabarcoding analysis (eDNA) of faeces and stable isotope analysis (SIA) of nitrogen (N) and carbon (C) in whole blood, to account for the high interindividual and temporal variability in the diets of multiple species simultaneously. eDNA showed regionalisation in the diet of smaller species, with land-use further defining dietary taxa within each region. SIA revealed that bioregion and land-use influence the δ13C values of all carnivore species and omnivores, whereas the δ15N values of these species are influenced only by land-use and not bioregion. Including multiple species showed that native rats are changing their diet in response to the presence of invasive rats, an impact that would have otherwise been attributed to land-use. Our findings demonstrate that human activities and invasive species are moulding the diets of invaded communities, raising questions about the potential impacts that dietary modifications will have on the life-history traits and the evolutionary consequences these modifications might have on the survival of native species. This highlights the urgency of including human activities in ecological studies and the importance of targeting multispecies assemblages to gain a better understanding of synergetic impacts on native biodiversity.

Isotopic niche partitioning in a multi-species assemblage

Isotopic niche partitioning in a multi-species assemblage

Legume-cereal intercropping as a strategy of regenerative agriculture supporting reverse of biodiversity loss - relevance of microbiome-based research

Adverse environmental impacts connceted with high chemicals and fertilizers use is one of the causes of biodiversity loss. Therefore, there is a need to looking for more natural and non-hazardous alternative approaches to make agriculture more sustain. The legume-cereal intercropping is currently one of the „hot topics” in the area of sustainable and regenerative agriculture. These intercropping practices are increasingly gaining attention as a way for enhancing soil ecosystem services and reversal biodiversity loss, as well as as a strategy of harnesing plant yield quality and soil health. Legume-cereal systems are the most common intercropping combinations used in sustainable agriculture models because of their noncompeting niche requirements and atmospheric nitrogen fixation which improve a balance of this nutrient in soil and plant and decrease the amount of mineral fertilizers use. However, conventional crop rotations in the EU are largely dominated by cereals while legume cultivation has declined in recent years. The idea of the LEGUMINOSE project includes that multi-species assemblages of plants deliver rhizosphere functions that are greater than the sum of the functions delivered by the rhizospheres of individual plants growing alone as a monoculture. We hypotheses that the higher plant diversity in intercropping will increase plant health, improve soil biodiversity and reduce the use of pesticides in agroecosystems. However ther is a knowledge gap concerning plant-soil-microbe interactions under root exudation from single and diverse plant assemblage and role of soil microbiomes in soil ecosystem functionality and plant production. Therefore we will focus on understanding these interactions by the microbiome research of soil and plant niches, including bulk soil, rhisozphere, roots and shoots of cereal and legume plants in order to assess the percentage of microbiota transfered between them within monocropping and intercropping fields and understand relationships of that microbiomes in plant health improvement. This project will design and implement sustainable environmental practices based on legume-cereal intercropping systems that account for the nature, impacting to global biogeosphere changes. Research funded in the frame of Horizon Europe Programme, agreement no. Project 101082289 — LEGUMINOSE.

From Child–Animal Relations to Multispecies Assemblages and Other-Than-Human Childhoods

This article discusses how childhood studies could be enriched with a focus on child–animal relations, multispecies assemblages and other-than-human childhoods. First, research on child–animal relations prior to, and at, the animal turn is presented. It is argued that the dominant utilitarian and adult-centered views respond poorly to the significance children themselves see in their relations with other-than-human animals. The article then moves on to the concept of multispecies assemblages. Viewing childhoods as multispecies from the outset allows one to draw attention to the specific and situated relationalities amidst natural, cultural, technological, economic, and political forces. Finally, attention is drawn to other-than-human childhoods. The differences, hierarchies, connections and unequal possibilities that arise from being born and growing up as a member of a distinct species amidst societal processes are discussed. Additionally, childhood is suggested to be an important concept through which to give detail, specificity, and a critical edge to the work of multispecies research.

Fossil evidence for sporeling development of a Mesozoic osmundaceous fern.

An anatomically preserved fossil fern sporeling has been discovered in a Lower Cretaceous marine concretion from Vancouver Island, British Columbia, Canada, providing an opportunity to characterize rhizome growth from an extinct species. The specimen was studied from serial transverse sections prepared by the cellulose acetate peel technique. The rhizome ranges from ~0.7 to 1.1 mm in diameter, has a sclerenchymatous pith, a stele that attains a dictyoxylic architecture, and sclerenchymatous outer cortex, features that are characteristic of osmundaceous rhizomes. Cauline xylem forms a medullated protostele or solenostele at some levels, but is dissected into discrete xylem bundles at others. Fronds diverge in a helical phyllotaxis, range up to 1.1 mm in greatest dimension, and have a C-shaped trace and outer cortex of sclerotic cells. Inside the sclerenchyma of the petioles are two lateral sclerotic strands and a sclerotic bundle adaxial to the trace. Together, these characters reveal the occurrence of a new species, Todea minutacaulis and provide evidence for developmental changes that occur in the rhizome as the sporeling increased in size. Small size of the specimen, medullated protostelic-dictyoxylic solenostelar vascular architecture, and incompletely sclerified cells apically reveal that osmundaceous sporeling development has remained constant since at least the Early Cretaceous. Together with Todea tidwellii and Osmunda vancouverensis that also are present in the Apple Bay flora, this sporeling documents the occurrence of a multispecies assemblage of osmundaceous ferns and demonstrates that the genus Todea was diversifying rapidly by the Early Cretaceous.

Shifts in the composition and distribution of Pacific Arctic larval fish assemblages in response to rapid ecosystem change.

The Pacific Arctic marine ecosystem has undergone rapid changes in recent years due to ocean warming, sea ice loss, and increased northward transport of Pacific-origin waters into the Arctic. These climate-mediated changes have been linked to range shifts of juvenile and adult subarctic (boreal) and Arctic fish populations, though it is unclear whether distributional changes are also occurring during the early life stages. We analyzed larval fish abundance and distribution data sampled in late summer from 2010 to 2019 in two interconnected Pacific Arctic ecosystems: the northern Bering Sea and Chukchi Sea, to determine whether recent warming and loss of sea ice has restricted habitat for Arctic species and altered larval fish assemblage composition from Arctic- to boreal-associated taxa. Multivariate analyses revealed the presence of three distinct multi-species assemblages across all years: (1) a boreal assemblage dominated by yellowfin sole (Limanda aspera), capelin (Mallotus catervarius), and walleye pollock (Gadus chalcogrammus); (2) an Arctic assemblage composed of Arctic cod (Boreogadus saida) and other common Arctic species; and (3) a mixed assemblage composed of the dominant species from the other two assemblages. We found that the wind- and current-driven northward advection of warmer, subarctic waters and the unprecedented low-ice conditions observed in the northern Bering and Chukchi seas beginning in 2017 and persisting into 2018 and 2019 have precipitated community-wide shifts, with the boreal larval fish assemblage expanding northward and offshore and the Arctic assemblage retreating poleward. We conclude that Arctic warming is most significantly driving changes in abundance at the leading and trailing edges of the Chukchi Sea larval fish community as boreal species increase in abundance and Arctic species decline. Our analyses document how quickly larval fish assemblages respond to environmental change and reveal that the impacts of Arctic borealization on fish community composition spans multiple life stages over large spatial scales.

Demystifying Cassiopea species identity in the Florida Keys: Cassiopea xamachana and Cassiopea andromeda coexist in shallow waters.

The phylogeny of the Upside-Down Jellyfish (Cassiopea spp.) has been revised multiple times in its history. This is especially true in the Florida Keys, where much of the Cassiopea stock for research and aquarium trade in the United States are collected. In August 2021, we collected 55 Cassiopea medusae at eight shallow water sites throughout the Florida Keys and sequenced COI, 16S, and 28S genes. Mitochondrial genes demonstrate that the shallow waters in Florida are inhabited by both Cassiopea xamachana and a non-native Cassiopea andromeda lineage, identified in multispecies assemblages at least thrice. While C. xamachana were present at all sites, the C. andromeda-mitotype individuals were present at only a minority of sites. While we cannot confirm hybridization or lack thereof between the C. xamanchana and C. andromeda lineages, these previously unknown multispecies assemblages are a likely root cause for the confusing and disputed COI-based species identities of Cassiopea in the Florida Keys. This also serves as a cautionary note to all Cassiopea researchers to barcode their individuals regardless of the location in which they were collected.

Multispecies assemblages and multiple stressors: Synthesizing the state of experimental research in freshwaters

AbstractRecent decades have witnessed a sharp biodiversity decline in freshwaters due to multiple stressors. The presence of multiple stressors is expected to affect community structure and interactions in freshwater ecosystems, with subsequent functional consequences. We synthesized the state of experimental, manipulative multiple‐stressor studies that focused on multispecies assemblages in freshwaters. Compared to rivers and lakes, wetland and groundwater ecosystems have received much less attention in identified multiple‐stressor research. Most of the identified studies investigated combinations of abiotic stressors (e.g., nutrients, pesticides, heavy metals, warming, altered flow and sedimentation) on microbes and invertebrates while biotic stressors and vertebrates have been largely overlooked. The responses of community structure (e.g., alpha diversity, biomass, and abundance), some community/ecosystem functions (e.g., photosynthesis and autotrophic activity, leaf litter degradation), and morphological traits like body size and growth forms were frequently investigated. We observed a clear gap in biotic interactions under multiple‐stressor conditions, which, although difficult to study, could impede a deeper mechanistic understanding of how multiple stressors affect freshwater assemblages and associated ecological processes. Although information on ecosystem recovery pathways following restoration is critical for freshwater management, few studies were designed to provide such information, signifying the disconnections between multiple‐stressor research and environmental practice. To bridge these gaps, researchers and environmental practitioners need to work together to identify key stressors and interactions at different spatial and temporal scales and prioritize stressor management. Such collaborations will enhance the translation of multiple‐stressor research into efficient management strategies to protect and restore freshwater ecosystems.This article is categorized under: Water and Life > Stresses and Pressures on Ecosystems Water and Life > Conservation, Management, and Awareness

Co-occurrence probabilities between mosquito vectors of West Nile and Eastern equine encephalitis viruses using Markov Random Fields (MRFcov)

Mosquito vectors of eastern equine encephalitis virus (EEEV) and West Nile virus (WNV) in the USA reside within broad multi-species assemblages that vary in spatial and temporal composition, relative abundances and vector competence. These variations impact the risk of pathogen transmission and the operational management of these species by local public health vector control districts. However, most models of mosquito vector dynamics focus on single species and do not account for co-occurrence probabilities between mosquito species pairs across environmental gradients. In this investigation, we use for the first time conditional Markov Random Fields (CRF) to evaluate spatial co-occurrence patterns between host-seeking mosquito vectors of EEEV and WNV around sampling sites in Manatee County, Florida. Specifically, we aimed to: (i) quantify correlations between mosquito vector species and other mosquito species; (ii) quantify correlations between mosquito vectors and landscape and climate variables; and (iii) investigate whether the strength of correlations between species pairs are conditional on landscape or climate variables. We hypothesized that either mosquito species pairs co-occur in patterns driven by the landscape and/or climate variables, or these vector species pairs are unconditionally dependent on each other regardless of the environmental variables. Our results indicated that landscape and bioclimatic covariates did not substantially improve the overall model performance and that the log abundances of the majority of WNV and EEEV vector species were positively dependent on other vector and non-vector mosquito species, unconditionally. Only five individual mosquito vectors were weakly dependent on environmental variables with one exception, Culiseta melanura, the primary vector for EEEV, which showed a strong correlation with woody wetland, precipitation seasonality and average temperature of driest quarter. Our analyses showed that majority of the studied mosquito species’ abundance and distribution are insignificantly better predicted by the biotic correlations than by environmental variables. Additionally, these mosquito vector species may be habitat generalists, as indicated by the unconditional correlation matrices between species pairs, which could have confounded our analysis, but also indicated that the approach could be operationalized to leverage species co-occurrences as indicators of vector abundances in unsampled areas, or under scenarios where environmental variables are not informative.Graphical

Conceptualising multispecies collaboration: Work, animal labour, and Nature‐based Solutions

AbstractTracing the story of beaver restoration across California, this paper investigates the emerging discourse of ‘working with nature’ through the lens of animal work and labour, exploring possibilities for, multispecies collaboration. At the intersection of animal geographies, environmental anthropology, and geographies of conservation, this paper finds three concurrent modes of working with beaver: beaver as labourer, beaver as coworker, and beaver as community. Beaver as labourer emerges as a mode where beavers go from material resource to low‐wage labourer, their liveliness predicated on their ability to be working for humans. Beaver as coworker transitions beavers from labourers to workers, respected for their skills as ecosystem engineers to be working with. Beaver as community emerges as a mode in which beavers and humans live with each other as kin, amidst wider multispecies assemblages. This mode sets the foundation to theorise the concept of multispecies collaboration, a term often used in the literature without definition. This paper explores the concept through theories of animal work and labour, challenging the premise of work altogether, while situating multispecies collaboration as an in‐between, a both/and space of working and living with ‘nature’. This paper serves as an reflection on the ways in which humans ‘work with nature’, in a time where various nonhumans are being made to be ‘workers’. It presents and analyses these relations, ruminates on implications for governance of these multispecies spaces, and develops the concept of multispecies collaboration as a critical consideration for Nature‐based Solutions.

Hydromorphological discontinuities deeply modify the benthic multi-species assemblage diversity in a Mediterranean running river

The aim of the study was to investigate the modifications of the macroinvertebrate multi-species assemblage in relation to hydromorphological discontinues, since macroinvertebrates are traditionally exploited in water quality assessment activities. Three sampling sites characterized by different hydrological characteristics were selected in five stations along the River Aniene in Central Italy. We evaluated the macroinvertebrate structure, traits, biotic and diversity indices in relation to the erosive power. Among macroinvertebrate taxa, Elminthidae and Chironomidae families showed a particular occurrence pattern associated with the site at the base of vertical drop, characterized by the stronger hydrodynamic. However, the water quality status was high, not showing differences between the three sites. Our finding has a novelty value as similar studies on the investigation of the hydromorphological discontinuities on macroinvertebrate structure and ecological traits are very scarce in the literature.Graphical abstract

An epigenetic DNA methylation clock for age estimates in Indo-Pacific bottlenose dolphins (Tursiops aduncus).

Knowledge of an animal's chronological age is crucial for understanding and predicting population demographics, survival and reproduction, but accurate age determination for many wild animals remains challenging. Previous methods to estimate age require invasive procedures, such as tooth extraction to analyse growth layers, which are difficult to carry out with large, mobile animals such as cetaceans. However, recent advances in epigenetic methods have opened new avenues for precise age determination. These 'epigenetic clocks' present a less invasive alternative and can provide age estimates with unprecedented accuracy. Here, we present a species-specific epigenetic clock based on skin tissue samples for a population of Indo-Pacific bottlenose dolphins (Tursiops aduncus) in Shark Bay, Western Australia. We measured methylation levels at 37,492 cytosine-guanine sites (CpG sites) in 165 samples using the mammalian methylation array. Chronological age estimates with an accuracy of ±1 year were available for 68 animals as part of a long-term behavioral study of this population. Using these samples with known age, we built an elastic net model with Leave-One-Out-Cross-Validation, which retained 43 CpG sites, providing an r= 0.86 and median absolute age error (MAE)=2.1 years (5% of maximum age). This model was more accurate for our data than the previously published methylation clock based on skin samples of common bottlenose dolphins (T. truncatus: r= 0.83, MAE=2.2) and the multi-species odontocete methylation clock (r= 0.68, MAE=6.8), highlighting that species-specific clocks can have superior performance over those of multi-species assemblages. We further developed an epigenetic sex estimator, predicting sex with 100% accuracy. As age and sex are critical parameters for the study of animal populations, this clock and sex estimator will provide a useful tool for extracting life history information from skin samples rather than long-term observational data for free-ranging Indo-Pacific bottlenose dolphins worldwide.

Emerging harmful algal blooms caused by distinct seasonal assemblages of a toxic diatom.

Diatoms in the Pseudo-nitzschia genus produce the neurotoxin domoic acid. Domoic acid bioaccumulates in shellfish, causing illness in humans and marine animals upon ingestion. In 2017, high domoic acid levels in shellfish meat closed shellfish harvest in Narragansett Bay, Rhode Island for the first and only time in history, although abundant Pseudo-nitzschia have been observed for over 60 years. To investigate whether an environmental factor altered endemic Pseudo-nitzschia physiology or new domoic acid-producing strain(s) were introduced to Narragansett Bay, we conducted weekly sampling from 2017 to 2019 and compared closure samples. Plankton-associated domoic acid was quantified by LC-MS/MS and Pseudo-nitzschia spp. were identified using a taxonomically improved high-throughput rDNA sequencing approach. Comparison with environmental data revealed a detailed understanding of domoic acid dynamics and seasonal multi-species assemblages. Plankton-associated domoic acid was low throughout 2017-2019, but recurred in fall and early summer maxima. Fall domoic acid maxima contained known toxic species as well as a novel Pseudo-nitzschia genotype. Summer domoic acid maxima included fewer species but also known toxin producers. Most 2017 closure samples contained the particularly concerning toxic species, P. australis, which also appeared infrequently during 2017-2019. Recurring Pseudo-nitzschia assemblages were driven by seasonal temperature changes, and plankton-associated domoic acid correlated with low dissolved inorganic nitrogen. Thus, the Narragansett Bay closures were likely caused by both resident assemblages that become toxic depending on nutrient status as well as the episodic introductions of toxic species from oceanographic and climatic shifts.

Movimento Negro in Salvador de Bahia: an alliance between things

Walking through Salvador de Bahia’s streets one perceives the presence of symbols of the culture of struggle promoted by the Movimento Negro, which invites to encher o espaço (“fill the space”) with celebratory representations of Afro-descent, in response to local structural racism. An attempt was made to understand who or what the Movimento Negro was through fieldwork. The centrality of the material and sensitive dimension, as a space for struggle among economic and racial groups (Rancière 2004), has emerged. Both racism and the forms of resistance in response to it are visible and materially manifest in bodies, spaces, and objects. Movimento Negro is a hyperobject (Morton 2018). It’s a “multispecies assemblage” (Haraway 2015): caught in its sensual manifestations, it forces us to question the local system of meaning and the very epistemological paradigms on which Modernity is based (Gilroy 1993).

Pathogens and predators: examining the separate and combined effects of natural enemies on assemblage structure.

Natural enemy ecology strives to unify predator-prey and host-pathogen interactions under a common framework to gain insights into community- and ecosystem-level processes. To address this goal, ecologists need a greater emphasis on: (1) quantifying pathogen-mediated effects on community structure to enable comparisons with predator-mediated effects and (2) determining the interactive effects of combined natural enemies on communities. We conducted a mesocosm experiment to assess the individual and combined effects of predators (dragonfly larvae and adult water bugs) and a pathogen (ranavirus) on the abundance and composition of a larval amphibian assemblage. We found that our three natural enemies structured victim assemblages in unique ways, producing distinct assemblages. Additionally, we found that in combination treatments, predators mainly drove assemblage structure such that the assemblages most closely resembled their respective predator treatments. We also found that predators reduced infection prevalence in combination treatments, and that the magnitude of this effect was dependent on predator identity. Compared to virus-alone treatments, the presence of dragonflies and water bugs reduced infection prevalence by 79% and 63%, respectively. Additionally, the presence of dragonflies eliminated ranavirus infection in two species, which demonstrates the prominent role of predators in disease dynamics in this system. Overall, this work demonstrates the importance of considering natural enemies in community ecology, as each enemy can elicit a unique structural change. Additionally, this study provides a unique empirical test of the healthy herds hypothesis for multi-species assemblages and underscores the importance of advancing our understanding of multi-enemy interactions within communities.

Pestering capitalism: thinking with Halyomorpha halys about multispecies relations and ecological unsustainability

Many non-human species trouble human-oriented forms of multispecies life, which leads to classifying some of these species as pests. One of the fields of daily life most disturbed by the action of pests is modern capitalist agriculture, leading to different types of pest management by which human beings attempt to eliminate pests' opposition to the anthropogenic appropriation of the life-making efforts and energy of multispecies assemblages, an appropriation which is essential for capital circulation. In dominant modern capitalist cosmologies, the disturbances caused by pests automatically justify and require their attempted extermination. Without denying that pests are troubling, I argue that the technoscientific framing of human relationships with these species is insufficient as a way of understanding and interacting with them. Rather than exclusively seeing pests as a problem, the manner in which humans interact with these species points us to several foundational – and in themselves problematic – aspects of modern capitalist world-ecology. Taking my research on networks concerned with kiwifruit farming and commercialization in Portugal as a basis for my arguments, I look at how actors in these networks propose to deal with Halyomorpha halys, the brown marmorated stink bug, in an attempt to think with this species about the (inextricably connected) socio-ecological unsustainability of modern capitalist world-ecology and the bio-thanato-political strategies of immunization employed to deal with non-human species in this political ecological system.