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1.
J R Soc Interface ; 21(216): 20240278, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38955228

RESUMO

The wildlife and livestock interface is vital for wildlife conservation and habitat management. Infectious diseases maintained by domestic species may impact threatened species such as Asian bovids, as they share natural resources and habitats. To predict the population impact of infectious diseases with different traits, we used stochastic mathematical models to simulate the population dynamics over 100 years for 100 times in a model gaur (Bos gaurus) population with and without disease. We simulated repeated introductions from a reservoir, such as domestic cattle. We selected six bovine infectious diseases; anthrax, bovine tuberculosis, haemorrhagic septicaemia, lumpy skin disease, foot and mouth disease and brucellosis, all of which have caused outbreaks in wildlife populations. From a starting population of 300, the disease-free population increased by an average of 228% over 100 years. Brucellosis with frequency-dependent transmission showed the highest average population declines (-97%), with population extinction occurring 16% of the time. Foot and mouth disease with frequency-dependent transmission showed the lowest impact, with an average population increase of 200%. Overall, acute infections with very high or low fatality had the lowest impact, whereas chronic infections produced the greatest population decline. These results may help disease management and surveillance strategies support wildlife conservation.


Assuntos
Modelos Biológicos , Dinâmica Populacional , Animais , Tailândia/epidemiologia , Bovinos , Animais Selvagens , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/veterinária , Doenças Transmissíveis/transmissão , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Ruminantes/microbiologia
3.
Bull Math Biol ; 86(8): 101, 2024 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-38970749

RESUMO

We establish a general framework using a diffusion approximation to simulate forward-in-time state counts or frequencies for cladogenetic state-dependent speciation-extinction (ClaSSE) models. We apply the framework to various two- and three-region geographic-state speciation-extinction (GeoSSE) models. We show that the species range state dynamics simulated under tree-based and diffusion-based processes are comparable. We derive a method to infer rate parameters that are compatible with given observed stationary state frequencies and obtain an analytical result to compute stationary state frequencies for a given set of rate parameters. We also describe a procedure to find the time to reach the stationary frequencies of a ClaSSE model using our diffusion-based approach, which we demonstrate using a worked example for a two-region GeoSSE model. Finally, we discuss how the diffusion framework can be applied to formalize relationships between evolutionary patterns and processes under state-dependent diversification scenarios.


Assuntos
Simulação por Computador , Extinção Biológica , Especiação Genética , Conceitos Matemáticos , Modelos Biológicos , Filogenia , Animais , Modelos Genéticos , Evolução Biológica , Dinâmica Populacional/estatística & dados numéricos
4.
Mol Genet Genomics ; 299(1): 67, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980527

RESUMO

India's rich diversity encompasses individuals from varied geographical, cultural, and ethnic backgrounds. In the field of population genetics, comprehending the genetic diversity across distinct populations plays a crucial role. This study presents significant findings from genetic data obtained from the Sikkimese population of India. Autosomal markers were crucial for evaluating forensic parameters, with a combined paternity index of 1 × 109. Notably, Penta E emerged as a distinguishing marker for individual identification in the Sikkim population. Fst genetic distance values revealed insights into genetic isolation among different groups, enhancing our understanding of population dynamics in the central Himalayan region. The NJ-based phylogenetic tree highlighted close genetic relationships, of the Sikkim population with the Nepalese population surrounding neighbouring Himalayan populations providing glimpses into common ancestry. In summary, this study contributes valuable data to population genetics and underscores the importance of genetic variation in comprehending population dynamics and forensic applications.


Assuntos
Variação Genética , Genética Populacional , Filogenia , Dinâmica Populacional , Humanos , Índia , Siquim , Masculino , Repetições de Microssatélites/genética , Etnicidade/genética , Feminino
5.
Bull Math Biol ; 86(8): 102, 2024 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-38976154

RESUMO

This study presents a comprehensive analysis of a two-patch, two-life stage SI model without recovery from infection, focusing on the dynamics of disease spread and host population viability in natural populations. The model, inspired by real-world ecological crises like the decline of amphibian populations due to chytridiomycosis and sea star populations due to Sea Star Wasting Disease, aims to understand the conditions under which a sink host population can present ecological rescue from a healthier, source population. Mathematical and numerical analyses reveal the critical roles of the basic reproductive numbers of the source and sink populations, the maturation rate, and the dispersal rate of juveniles in determining population outcomes. The study identifies basic reproduction numbers R 0 for each of the patches, and conditions for the basic reproduction numbers to produce a receiving patch under which its population. These findings provide insights into managing natural populations affected by disease, with implications for conservation strategies, such as the importance of maintaining reproductively viable refuge populations and considering the effects of dispersal and maturation rates on population recovery. The research underscores the complexity of host-pathogen dynamics in spatially structured environments and highlights the need for multi-faceted approaches to biodiversity conservation in the face of emerging diseases.


Assuntos
Anfíbios , Número Básico de Reprodução , Epidemias , Interações Hospedeiro-Patógeno , Conceitos Matemáticos , Modelos Biológicos , Dinâmica Populacional , Animais , Número Básico de Reprodução/estatística & dados numéricos , Epidemias/estatística & dados numéricos , Anfíbios/microbiologia , Anfíbios/crescimento & desenvolvimento , Dinâmica Populacional/estatística & dados numéricos , Estrelas-do-Mar/crescimento & desenvolvimento , Estrelas-do-Mar/microbiologia , Estágios do Ciclo de Vida , Quitridiomicetos/fisiologia , Quitridiomicetos/patogenicidade , Modelos Epidemiológicos , Simulação por Computador
6.
J Math Biol ; 89(2): 22, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38951257

RESUMO

Group defense in prey and hunting cooperation in predators are two important ecological phenomena and can occur concurrently. In this article, we consider cooperative hunting in generalist predators and group defense in prey under a mathematical framework to comprehend the enormous diversity the model could capture. To do so, we consider a modified Holling-Tanner model where we implement Holling type IV functional response to characterize grazing pattern of predators where prey species exhibit group defense. Additionally, we allow a modification in the attack rate of predators to quantify the hunting cooperation among them. The model admits three boundary equilibria and up to three coexistence equilibrium points. The geometry of the nontrivial prey and predator nullclines and thus the number of coexistence equilibria primarily depends on a specific threshold of the availability of alternative food for predators. We use linear stability analysis to determine the types of hyperbolic equilibrium points and characterize the non-hyperbolic equilibrium points through normal form and center manifold theory. Change in the model parameters leading to the occurrences of a series of local bifurcations from non-hyperbolic equilibrium points, namely, transcritical, saddle-node, Hopf, cusp and Bogdanov-Takens bifurcation; there are also occurrences of global bifurcations such as homoclinic bifurcation and saddle-node bifurcation of limit cycles. We observe two interesting closed 'bubble' form induced by global bifurcations due to change in the strength of hunting cooperation and the availability of alternative food for predators. A three dimensional bifurcation diagram, concerning the original system parameters, captures how the alternation in model formulation induces gradual changes in the bifurcation scenarios. Our model highlights the stabilizing effects of group or gregarious behaviour in both prey and predator, hence supporting the predator-herbivore regulation hypothesis. Additionally, our model highlights the occurrence of "saltatory equilibria" in ecological systems and capture the dynamics observed for lion-herbivore interactions.


Assuntos
Ecossistema , Cadeia Alimentar , Conceitos Matemáticos , Modelos Biológicos , Dinâmica Populacional , Comportamento Predatório , Animais , Dinâmica Populacional/estatística & dados numéricos , Comportamento Cooperativo , Simulação por Computador , Herbivoria , Modelos Lineares
7.
J Math Biol ; 89(2): 24, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955850

RESUMO

The assembly and persistence of ecological communities can be understood as the result of the interaction and migration of species. Here we study a single community subject to migration from a species pool in which inter-specific interactions are organised according to a bipartite network. Considering the dynamics of species abundances to be governed by generalised Lotka-Volterra equations, we extend work on unipartite networks to we derive exact results for the phase diagram of this model. Focusing on antagonistic interactions, we describe factors that influence the persistence of the two guilds, locate transitions to multiple-attractor and unbounded phases, as well as identifying a region of parameter space in which consumers are essentially absent in the local community.


Assuntos
Ecossistema , Conceitos Matemáticos , Modelos Biológicos , Dinâmica Populacional , Dinâmica Populacional/estatística & dados numéricos , Animais , Cadeia Alimentar
8.
BMC Ecol Evol ; 24(1): 93, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38969976

RESUMO

The Persian fallow deer or Mesopotamian fallow Deer (Dama mesopotamica, Brook 1875), a species of significant ecological importance, had faced the threat of extinction in Iran. One conservation strategy involved the translocation of Persian deer to enclosed areas across Iran, where they were afforded protection from external threats and provided with essential care by human caretakers. While human caretakers diligently attend to their needs and mitigate external threats, climate variables may now become critical factors affecting population dynamics in enclosed areas. This study aims to assess the similarity in climate niches between the original area (Dez and Karkheh) of the Persian deer species and 11 newly enclosed areas. To achieve this, we employed climate data and ecological niche modeling (ENM) techniques to assess the variations in climate among 12 areas. We utilized the environmental equivalency test to determine whether the environmental spaces of area pairs exhibit significant differences and whether these spaces are interchangeable. Extrapolation analyses were also constructed in the next steps to explore climatic conditions in original fallow deer habitats that are non-analogous to those in other parts of Iran. Our results reveal significant disparities in climate conditions between the original and all translocated areas. Based on observations of population growth in specific enclosed areas where translocated deer populations have thrived, we hypothesize that the species may demonstrate a non-equilibrium distribution in Iran. Consequently, these new areas could potentially be regarded as part of the species' potential climate niche. Extrapolation analysis showed that for a significant portion of Iran, extrapolation predictions are highly uncertain and potentially unreliable for the translocation of Persian fallow deer. However, the primary objective of translocation efforts remains the establishment of self-sustaining populations of Persian deer capable of thriving in natural areas beyond enclosed areas, thus ensuring their long-term survival and contributing to preservation efforts. Evaluating the success of newly translocated species requires additional time, with varying levels of success observed. In cases where the growth rate of the species in certain enclosed areas falls below expectations, it is prudent to consider climate variables that may contribute to population declines. Furthermore, for future translocations, we recommend selecting areas with climate similarities to regions where the species has demonstrated growth rates.


Assuntos
Clima , Cervos , Ecossistema , Animais , Irã (Geográfico) , Cervos/fisiologia , Conservação dos Recursos Naturais , Dinâmica Populacional
9.
J R Soc Interface ; 21(216): 20240217, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38981516

RESUMO

Mathematical models in ecology and epidemiology must be consistent with observed data in order to generate reliable knowledge and evidence-based policy. Metapopulation systems, which consist of a network of connected sub-populations, pose technical challenges in statistical inference owing to nonlinear, stochastic interactions. Numerical difficulties encountered in conducting inference can obstruct the core scientific questions concerning the link between the mathematical models and the data. Recently, an algorithm has been proposed that enables computationally tractable likelihood-based inference for high-dimensional partially observed stochastic dynamic models of metapopulation systems. We use this algorithm to build a statistically principled data analysis workflow for metapopulation systems. Via a case study of COVID-19, we show how this workflow addresses the limitations of previous approaches. The COVID-19 pandemic provides a situation where mathematical models and their policy implications are widely visible, and we revisit an influential metapopulation model used to inform basic epidemiological understanding early in the pandemic. Our methods support self-critical data analysis, enabling us to identify and address model weaknesses, leading to a new model with substantially improved statistical fit and parameter identifiability. Our results suggest that the lockdown initiated on 23 January 2020 in China was more effective than previously thought.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , Humanos , Algoritmos , Modelos Biológicos , Dinâmica Populacional , Pandemias
10.
Proc Biol Sci ; 291(2026): 20240980, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38981521

RESUMO

Ecological and evolutionary predictions are being increasingly employed to inform decision-makers confronted with intensifying pressures on biodiversity. For these efforts to effectively guide conservation actions, knowing the limit of predictability is pivotal. In this study, we provide realistic expectations for the enterprise of predicting changes in ecological and evolutionary observations through time. We begin with an intuitive explanation of predictability (the extent to which predictions are possible) employing an easy-to-use metric, predictive power PP(t). To illustrate the challenge of forecasting, we then show that among insects, birds, fishes and mammals, (i) 50% of the populations are predictable at most 1 year in advance and (ii) the median 1-year-ahead predictive power corresponds to a prediction R 2 of only 20%. Predictability is not an immutable property of ecological systems. For example, different harvesting strategies can impact the predictability of exploited populations to varying degrees. Moreover, incorporating explanatory variables, accounting for time trends and considering multivariate time series can enhance predictability. To effectively address the challenge of biodiversity loss, researchers and practitioners must be aware of the information within the available data that can be used for prediction and explore efficient ways to leverage this knowledge for environmental stewardship.


Assuntos
Biodiversidade , Evolução Biológica , Conservação dos Recursos Naturais , Animais , Aves/fisiologia , Peixes/fisiologia , Insetos/fisiologia , Previsões , Mamíferos , Dinâmica Populacional , Modelos Biológicos
11.
Glob Chang Biol ; 30(7): e17413, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38982678

RESUMO

Tasmanian eucalypt forests are among the most carbon-dense in the world, but projected climate change could destabilize this critical carbon sink. While the impact of abiotic factors on forest ecosystem carbon dynamics have received considerable attention, biotic factors such as the input of animal scat are less understood. Tasmanian devils (Sarcophilus harrisii)-an osteophageous scavenger that can ingest and solubilize nutrients locked in bone material-may subsidize plant and microbial productivity by concentrating bioavailable nutrients (e.g., nitrogen and phosphorus) in scat latrines. However, dramatic declines in devil population densities, driven by the spread of a transmissible cancer, may have underappreciated consequences for soil organic carbon (SOC) storage and forest productivity by altering nutrient cycling. Here, we fuse experimental data and modeling to quantify and predict future changes to forest productivity and SOC under various climate and scat-quality futures. We find that devil scat significantly increases concentrations of nitrogen, ammonium, phosphorus, and phosphate in the soil and shifts soil microbial communities toward those dominated by r-selected (e.g., fast-growing) phyla. Further, under expected increases in temperature and changes in precipitation, devil scat inputs are projected to increase above- and below-ground net primary productivity and microbial biomass carbon through 2100. In contrast, when devil scat is replaced by lower-quality scat (e.g., from non-osteophageous scavengers and herbivores), forest carbon pools are likely to increase more slowly, or in some cases, decline. Together, our results suggest often overlooked biotic factors will interact with climate change to drive current and future carbon pool dynamics in Tasmanian forests.


Assuntos
Mudança Climática , Florestas , Marsupiais , Solo , Animais , Marsupiais/fisiologia , Solo/química , Tasmânia , Microbiologia do Solo , Ecossistema , Nitrogênio/metabolismo , Nitrogênio/análise , Fósforo/análise , Fósforo/metabolismo , Carbono/metabolismo , Carbono/análise , Dinâmica Populacional
12.
Nat Commun ; 15(1): 5637, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38965212

RESUMO

Climate warming is one of the facets of anthropogenic global change predicted to increase in the future, its magnitude depending on present-day decisions. The north Atlantic and Arctic Oceans are already undergoing community changes, with warmer-water species expanding northwards, and colder-water species retracting. However, the future extent and implications of these shifts remain unclear. Here, we fitted a joint species distribution model to occurrence data of 107, and biomass data of 61 marine fish species from 16,345 fishery independent trawls sampled between 2004 and 2022 in the northeast Atlantic Ocean, including the Barents Sea. We project overall increases in richness and declines in relative dominance in the community, and generalised increases in species' ranges and biomass across three different future scenarios in 2050 and 2100. The projected decline of capelin and the practical extirpation of polar cod from the system, the two most abundant species in the Barents Sea, drove an overall reduction in fish biomass at Arctic latitudes that is not replaced by expanding species. Furthermore, our projections suggest that Arctic demersal fish will be at high risk of extinction by the end of the century if no climate refugia is available at eastern latitudes.


Assuntos
Biomassa , Mudança Climática , Peixes , Animais , Regiões Árticas , Oceano Atlântico , Mar do Norte , Biodiversidade , Ecossistema , Oceanos e Mares , Aquecimento Global , Dinâmica Populacional
13.
PLoS Negl Trop Dis ; 18(6): e0012237, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38885272

RESUMO

BACKGROUND: Leishmaniasis, a neglected disease and public health concern, is associated with various factors such as biological, social, economical conditions and climate, increasing the risk of human infection. Understanding the population dynamics of the vectors, like Pintomyia longiflocosa, and its relationship with ecological variables is crucial for developing effective strategies to control sand fly populations and combat cutaneous leishmaniasis in a tropical country like Colombia. METHODOLOGY: Adult sand flies were collected in three different sample locations: outdoor, indoor, and peri-domestic areas in three houses located in the rural settlement of Campoalegre (Huila) between February 2020 and February 2021, using the CDC light traps. The sand fly density was quantified and associated with the sample locations and the sampling months using Analysis of Variance and Pearson correlations. PRINCIPAL FINDINGS: In the period of the sample, 98.86% of sand fly collected was identified as Pi. longiflocosa. The density of this species was significantly different between males and females, the latter contributing more to density in all sample locations (P<0.0001). The outdoor was the sample location with the highest and most significative density in this study (70%, P = 0.04). The density of these sand flies is related to the seasonality of Campoalegre, revealing a density peak from February and June to October (P < 0.05). Finally, precipitation is the environmental variable prominently linked to the density pattern, showing a negative correlation with it. Months with the highest precipitations show the lowest values of Pi. longiflocosa abundance. CONCLUSIONS/SIGNICANCE: Our investigation reveals a inverse correlation between precipitation levels and the abundance of Pi. longiflocosa in Campoalegre (Huila), particularly in outdoor areas. This suggests that vector control strategies to periods of reduced precipitation in outdoor settings could offer an effective approach to minimizing cases of cutaneous leishmaniasis in the region.


Assuntos
Insetos Vetores , Leishmaniose Cutânea , Psychodidae , Animais , Leishmaniose Cutânea/transmissão , Leishmaniose Cutânea/epidemiologia , Colômbia/epidemiologia , Psychodidae/parasitologia , Psychodidae/fisiologia , Insetos Vetores/fisiologia , Insetos Vetores/parasitologia , Feminino , Masculino , Humanos , Estações do Ano , Dinâmica Populacional , Análise Espaço-Temporal
14.
Sci Rep ; 14(1): 14828, 2024 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937608

RESUMO

This work studies changes in the demographics of the different spatial units that make up the Andalusia region in Spain throughout the year 2021, with the aim of seeing the progressive recovery of the population after the COVID-19 pandemic. Mobile phone data from Origin-Destination matrices has been used, due to the ease of obtaining updated information quickly and constantly. A methodology has been developed to transform the number of travelers into an estimated population without biases, and an interpolation function has been used to take into account all the data available in the year 2021. Results show a direct link between the demographic changes in Andalusia and the removal of the mobility restrictions caused by the COVID-19 pandemic, with an increase of non-related work mobility and a decrease of static population. Travel distances between home and work places are also affected, with an increase of long trips after the end of the mobility restrictions. In addition, different patterns have been visualized, such as the concentration of commuting in the metropolitan areas of the region during working days, the population growth in rural areas during weekends, or the population displacement to coastal areas in summer.


Assuntos
COVID-19 , Telefone Celular , Viagem , COVID-19/epidemiologia , Humanos , Espanha/epidemiologia , Viagem/estatística & dados numéricos , SARS-CoV-2/isolamento & purificação , Pandemias , Dinâmica Populacional , Demografia
15.
Ecology ; 105(7): e4327, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38859712

RESUMO

Hierarchical models can express ecological dynamics using a combination of fixed and random effects, and measurement of their complexity (effective degrees of freedom, EDF) requires estimating how much random effects are shrunk toward a shared mean. Estimating EDF is helpful to (1) penalize complexity during model selection and (2) to improve understanding of model behavior. I applied the conditional Akaike Information Criterion (cAIC) to estimate EDF from the finite-difference approximation to the gradient of model predictions with respect to each datum. I confirmed that this has similar behavior to widely used Bayesian criteria, and I illustrated ecological applications using three case studies. The first compared model parsimony with or without time-varying parameters when predicting density-dependent survival, where cAIC favors time-varying demographic parameters more than conventional Akaike Information Criterion. The second estimates EDF in a phylogenetic structural equation model, and identifies a larger EDF when predicting longevity than mortality rates in fishes. The third compares EDF for a species distribution model fitted for 20 bird species and identifies those species requiring more model complexity. These highlight the ecological and statistical insight from comparing EDF among experimental units, models, and data partitions, using an approach that can be broadly adopted for nonlinear ecological models.


Assuntos
Modelos Biológicos , Animais , Ecossistema , Aves/fisiologia , Peixes/fisiologia , Dinâmica Populacional
16.
Ecol Appl ; 34(5): e3003, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38890813

RESUMO

Large terrestrial mammals increasingly rely on human-modified landscapes as anthropogenic footprints expand. Land management activities such as timber harvest, agriculture, and roads can influence prey population dynamics by altering forage resources and predation risk via changes in habitat, but these effects are not well understood in regions with diverse and changing predator guilds. In northeastern Washington state, USA, white-tailed deer (Odocoileus virginianus) are vulnerable to multiple carnivores, including recently returned gray wolves (Canis lupus), within a highly human-modified landscape. To understand the factors governing predator-prey dynamics in a human context, we radio-collared 280 white-tailed deer, 33 bobcats (Lynx rufus), 50 cougars (Puma concolor), 28 coyotes (C. latrans), and 14 wolves between 2016 and 2021. We first estimated deer vital rates and used a stage-structured matrix model to estimate their population growth rate. During the study, we observed a stable to declining deer population (lambda = 0.97, 95% confidence interval: 0.88, 1.05), with 74% of Monte Carlo simulations indicating population decrease and 26% of simulations indicating population increase. We then fit Cox proportional hazard models to evaluate how predator exposure, use of human-modified landscapes, and winter severity influenced deer survival and used these relationships to evaluate impacts on overall population growth. We found that the population growth rate was dually influenced by a negative direct effect of apex predators and a positive effect of timber harvest and agricultural areas. Cougars had a stronger effect on deer population dynamics than wolves, and mesopredators had little influence on the deer population growth rate. Areas of recent timber harvest had 55% more forage biomass than older forests, but horizontal visibility did not differ, suggesting that timber harvest did not influence predation risk. Although proximity to roads did not affect the overall population growth rate, vehicle collisions caused a substantial proportion of deer mortalities, and reducing these collisions could be a win-win for deer and humans. The influence of apex predators and forage indicates a dual limitation by top-down and bottom-up factors in this highly human-modified system, suggesting that a reduction in apex predators would intensify density-dependent regulation of the deer population owing to limited forage availability.


Assuntos
Cervos , Dinâmica Populacional , Lobos , Animais , Cervos/fisiologia , Lobos/fisiologia , Humanos , Comportamento Predatório , Washington , Atividades Humanas , Coiotes/fisiologia , Puma/fisiologia , Cadeia Alimentar , Ecossistema , Lynx/fisiologia
17.
Philos Trans R Soc Lond B Biol Sci ; 379(1907): 20230125, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-38913054

RESUMO

Dispersal plays a pivotal role in the eco-evolutionary dynamics of spatially structured populations, communities and ecosystems. As an individual-based trait, dispersal is subject to both plasticity and evolution. Its dependence on conditions and context is well understood within single-species metapopulations. However, species do not exist in isolation; they interact locally through various horizontal and vertical interactions. While the significance of species interactions is recognized for species coexistence and food web functioning, our understanding of their influence on regional dynamics, such as their impact on spatial dynamics in metacommunities and meta-food webs, remains limited. Building upon insights from behavioural and community ecology, we aim to elucidate biodiversity as both a driver and an outcome of connectivity. By synthesizing conceptual, theoretical and empirical contributions from global experts in the field, we seek to explore how a more mechanistic understanding of diversity-dispersal relationships influences the distribution of species in spatially and temporally changing environments. Our findings highlight the importance of explicitly considering interspecific interactions as drivers of dispersal, thus reshaping our understanding of fundamental dynamics including species coexistence and the emergent dynamics of metacommunities and meta-ecosystems. We envision that this initiative will pave the way for advanced forecasting approaches to understanding biodiversity dynamics under the pressures of global change. This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'.


Assuntos
Distribuição Animal , Biodiversidade , Evolução Biológica , Cadeia Alimentar , Animais , Ecossistema , Dinâmica Populacional , Modelos Biológicos
18.
J R Soc Interface ; 21(215): 20240042, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38916901

RESUMO

The component Allee effect (AE) is the positive correlation between an organism's fitness component and population density. Depending on the population spatial structure, which determines the interactions between organisms, a component AE might lead to positive density dependence in the population per-capita growth rate and establish a demographic AE. However, existing spatial models impose a fixed population spatial structure, which limits the understanding of how a component AE and spatial dynamics jointly determine the existence of demographic AEs. We introduce a spatially explicit theoretical framework where spatial structure and population dynamics are emergent properties of the individual-level demographic and movement rates. This framework predicts various spatial patterns depending on its specific parametrization, including evenly spaced aggregates of organisms, which determine the demographic-level by-products of the component AE. We find that aggregation increases population abundance and allows population survival in harsher environments and at lower global population densities when compared with uniformly distributed organisms. Moreover, aggregation can prevent the component AE from manifesting at the population level or restrict it to the level of each independent aggregate. These results provide a mechanistic understanding of how component AEs might operate for different spatial structures and manifest at larger scales.


Assuntos
Modelos Biológicos , Dinâmica Populacional , Animais , Densidade Demográfica
19.
Philos Trans R Soc Lond B Biol Sci ; 379(1907): 20230136, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-38913053

RESUMO

Decisions to disperse from a habitat stand out among organismal behaviours as pivotal drivers of ecosystem dynamics across scales. Encounters with other species are an important component of adaptive decision-making in dispersal, resulting in widespread behaviours like tracking resources or avoiding consumers in space. Despite this, metacommunity models often treat dispersal as a function of intraspecific density alone. We show, focusing initially on three-species network motifs, that interspecific dispersal rules generally drive a transition in metacommunities from homogeneous steady states to self-organized heterogeneous spatial patterns. However, when ecologically realistic constraints reflecting adaptive behaviours are imposed-prey tracking and predator avoidance-a pronounced homogenizing effect emerges where spatial pattern formation is suppressed. We demonstrate this effect for each motif by computing master stability functions that separate the contributions of local and spatial interactions to pattern formation. We extend this result to species-rich food webs using a random matrix approach, where we find that eventually, webs become large enough to override the homogenizing effect of adaptive dispersal behaviours, leading once again to predominately pattern-forming dynamics. Our results emphasize the critical role of interspecific dispersal rules in shaping spatial patterns across landscapes, highlighting the need to incorporate adaptive behavioural constraints in efforts to link local species interactions and metacommunity structure. This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'.


Assuntos
Distribuição Animal , Cadeia Alimentar , Modelos Biológicos , Animais , Ecossistema , Dinâmica Populacional , Comportamento Predatório
20.
Philos Trans R Soc Lond B Biol Sci ; 379(1907): 20230126, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-38913056

RESUMO

Dispersal among local communities is fundamental to the metacommunity concept but is only important to the metacommunity structure if dispersal causes distortions of species abundances away from what local ecological conditions favour. We know from much previous work that dispersal can cause such abundance distortions. However, almost all previous theoretical studies have only considered one species alone or two interacting species (e.g. competitors or predator and prey). Moreover, a systematic analysis is needed of whether different dispersal strategies (e.g. passive dispersal versus demographic habitat selection) result in different abundance distortion patterns, how these distortion patterns change with local food web structure, and how the dispersal propensities of the interacting species might evolve in response to one another. In this article, we show using computer simulations and analytical models that abundance distortions occur in simple food webs with both passive dispersal and habitat selection, but habitat selection causes larger distortions. Additionally, patterns in the evolution of dispersal propensity in interacting species are very different for these two dispersal strategies. This study identifies that the dispersal strategies employed by interacting species critically shape how dispersal will influence metacommunity structure. This article is part of the theme issue 'Diversity-dependence of dispersal: interspecific interactions determine spatial dynamics'.


Assuntos
Evolução Biológica , Ecossistema , Cadeia Alimentar , Modelos Biológicos , Distribuição Animal , Animais , Simulação por Computador , Biota , Dinâmica Populacional
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