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Revilla, T.A. & Křivan, V. (2018), "Competition, trait-mediated facilitation, and the structure of plant-pollinator communities", Journal of Theoretical Biology. Vol. 440, pp. 42-57.
Abstract: In plant--pollinator communities many pollinators are potential generalists and their preferences for certain plants can change quickly in response to changes in plant and pollinator densities. These changes in preferences affect coexistence within pollinator guilds as well as within plant guilds. Using a mathematical model, we study how adaptations of pollinator preferences influence population dynamics of a two-plant--two-pollinator community interaction module. Adaptation leads to coexistence between generalist and specialist pollinators, and produces complex plant population dynamics, involving alternative stable states and discrete transitions in the plant community. Pollinator adaptation also leads to plant--plant apparent facilitation that is mediated by changes in pollinator preferences. We show that adaptive pollinator behavior reduces niche overlap and leads to coexistence by specialization on different plants. Thus, this article documents how adaptive pollinator preferences for plants change the structure and coexistence of plant--pollinator communities.
BibTeX:
@article{revilla_krivan-jtb18,
  author = {Revilla, T. A. and Křivan, V.},
  title = {Competition, trait-mediated facilitation, and the structure of plant-pollinator communities},
  journal = {Journal of Theoretical Biology},
  year = {2018},
  volume = {440},
  pages = {42--57},
  doi = {http://doi.org/10.1016/j.jtbi.2017.12.019}
}
Revilla, T.A. & Křivan, V. (2016), "Pollinator Foraging Adaptation and Coexistence of Competing Plants", PLoS ONE. Vol. 11(8), pp. e0160076.
Abstract: We use the optimal foraging theory to study coexistence between two plant species and a generalist pollinator. We compare conditions for plant coexistence for non-adaptive vs. adaptive pollinators that adjust their foraging strategy to maximize fitness. When pollinators have fixed preferences, we show that plant coexistence typically requires both weak competition between plants for resources (e.g., space or nutrients) and pollinator preferences that are not too biased in favour of either plant. We also show how plant coexistence is promoted by indirect facilitation via the pollinator. When pollinators are adaptive foragers, pollinator’s diet maximizes pollinator’s fitness measured as the per capita population growth rate. Simulations show that this has two conflicting consequences for plant coexistence. On the one hand, when competition between pollinators is weak, adaptation favours pollinator specialization on the more profitable plant which increases asymmetries in plant competition and makes their coexistence less likely. On the other hand, when competition between pollinators is strong, adaptation promotes generalism, which facilitates plant coexistence. In addition, adaptive foraging allows pollinators to survive sudden loss of the preferred plant host, thus preventing further collapse of the entire community.
BibTeX:
@article{revilla_krivan-plosone16,
  author = {Revilla, T. A. and Křivan, V.},
  title = {Pollinator Foraging Adaptation and Coexistence of Competing Plants},
  journal = {PLoS ONE},
  year = {2016},
  volume = {11},
  number = {8},
  pages = {e0160076},
  doi = {http://dx.doi.org/10.1371/journal.pone.0160076}
}
Revilla, T.A. & Encinas-Viso, F. (2016), "Ecología y Evolución de la Endozoocoria", Acta Biologica Venezuelica. Vol. 35(2), pp. 187-215.
Abstract: La dispersión de semillas por animales juega un papel muy importante en el mantenimiento de la viabilidad de las poblaciones de plantas. Una de sus formas mas conspicuas es la endozoocoria, es decir la dispersión de semillas por frugívoros. En este trabajo construimos un modelo dinámico que considera varios aspectos esenciales de la endozoocoria, tales como el ciclo de vida de las plantas, y las características de consumo de los frugívoros. Con este modelo, encontramos que la supervivencia de las semillas a la frugivoría tiene una influencia desproporcionadamente grande sobre la abundancia vegetal. También encontramos que factores de regulación denso-dependientes hacen que los beneficios de la endozoocoria sean limitados. Tomando en consideración que las adaptaciones para la endozoocoria involucran costos para la planta, usamos nuestro modelo para estudiar la evolución de rasgos destinados a atraer animales. En condiciones de selección denso-independiente, la endozoocoria tiende a ser desfavorable si los costos involucrados son altos. En condiciones de selección denso-dependiente, la endozoocoria es favorable incluso cuando los costos son altos. Escenarios especiales de mortalidad denso-independientes y denso-dependientes, y de fisiología sensorial de los animales, contribuyen a la diversificación evolutiva de la endozoocoria.
BibTeX:
@Article{revilla_encinas-abv16,
  author =    {Revilla, T. A. and Encinas-Viso, F.},
  title =     {{E}cología y {E}volución de la {E}ndozoocoria},
  journal =   {{A}cta {B}iologica {V}enezuelica},
  year =      {2016},
  volume =    {35},
  number =    {2},
  pages =     {187--215},
  owner =     {tommy},
  timestamp = {2016.05.24},
  url =       {http://190.169.94.12/ojs/index.php/revista_abv/article/view/10317}
}
Revilla, T.A. (2015), "Numerical responses in resource-based mutualisms: a time scale approach", Journal of Theoretical Biology. Vol. 378, pp. 39-46.
Abstract: Many mutualisms involve inter-specific resource exchanges, making consumer--resource approaches ideal for studying their dynamics. Also in many cases these resources are short lived (e.g. flowers) compared with the population dynamics of their producers and consumers (e.g. plants and insects), which justifies a separation of time scales. As a result, we can derive the numerical response of one species with respect to the abundance of another. For resource consumers, the numerical responses can account for intra-specific competition for mutualistic resources (e.g. nectar), thus connecting competition theory and mutualism mechanistically. For species that depend on services (e.g. pollination, seed dispersal), the numerical responses display saturation of benefits, with service handling times related with rates of resource production (e.g. flower turnover time). In both scenarios, competition and saturation have the same underlying cause, which is that resource production occurs at a finite velocity per individual, but their consumption tracks the much faster rates of population growth characterizing mutualisms. The resulting models display all the basic features seen in many models of facultative and obligate mutualisms, and they can be generalized from species pairs to larger communities
BibTeX:
@article{revilla-jtb15,
  author = {Revilla, T. A.},
  title = {Numerical responses in resource-based mutualisms: a time scale approach},
  journal = {Journal of Theoretical Biology},
  year = {2015},
  volume = {378},
  pages = {39--46},
  note = {IF: 2.303},
  doi = {http://dx.doi.org/10.1016/j.jtbi.2015.04.012}
}
Revilla, T.A. & Encinas-Viso, F. (2015), "Dynamical transitions in a pollination--herbivory interaction: a conflict between mutualism and antagonism", PLoS ONE. Vol. 10(2), pp. e0117964.
Abstract: Plant-pollinator associations are often seen as purely mutualistic, while in reality they can be more complex. Indeed they may also display a diverse array of antagonistic interactions, such as competition and victim-exploiter interactions. In some cases mutualistic and antagonistic interactions are carried-out by the same species but at different life-stages. As a consequence, population structure affects the balance of inter-specific associations, a topic that is receiving increased attention. In this paper, we developed a model that captures the basic features of the interaction between a flowering plant and an insect with a larval stage that feeds on the plant's vegetative tissues (e.g. leaves) and an adult pollinator stage. Our model is able to display a rich set of dynamics, the most remarkable of which involves victim-exploiter oscillations that allow plants to attain abundances above their carrying capacities and the periodic alternation between states dominated by mutualism or antagonism. Our study indicates that changes in the insect's life cycle can modify the balance between mutualism and antagonism, causing important qualitative changes in the interaction dynamics. These changes in the life cycle could be caused by a variety of external drivers, such as temperature, plant nutrients, pesticides and changes in the diet of adult pollinators.
BibTeX:
@article{revilla_encinas-plosone15,
  author = {Revilla, T. A. and Encinas-Viso, F.},
  title = {Dynamical transitions in a pollination--herbivory interaction: a conflict between mutualism and antagonism},
  journal = {PLoS ONE},
  year = {2015},
  volume = {10},
  number = {2},
  pages = {e0117964},
  doi = {http://dx.doi.org/10.1371/journal.pone.0117964}
}
Revilla, T.A., Encinas-Viso, F. & Loreau, M. (2015), "Robustness of plant-pollinator networks under phenological change and habitat destruction", Oikos. Vol. 124(1), pp. 22-32.
Abstract: Climate change can alter species phenologies and therefore disrupt species interactions. Habitat destruction can damage biodiversity and population viability. However, we still know very little about the potential effects of these two factors on the diversity and structure of interaction networks when both act simultaneously. Here we developed a mutualistic metacommunity model to explore the effects of habitat destruction and phenological changes on the diversity and structure of plant–pollinator networks. Using an empirical data set of plant and pollinator interactions and their duration in days, we simulated increasing levels of habitat destruction, under projected scenarios of phenological shifts as well for historically recorded changes in phenologies. On one hand, we found that habitat destruction causes catastrophic collapse in global diversity, as well as inducing alternative states. On the other hand, phenological shifts tend to make interactions weaker, increasing local extinction rates. Together, habitat destruction and phenological changes act synergistically, making metacommunities even more vulnerable to global collapse. Metacommunities are also more vulnerable to collapses under scenarios of historical change, in which phenologies are shortened, not just shifted. Furthermore, connectance and nestedness tends to decrease gradually with habitat destruction before the global collapse. Small phenological shifts can raise connectance slightly, due novel interactions appearing in a few generalist species, but larger shifts always reduce connectance. We conclude that the robustness of mutualistic metacommunities against habitat destruction can be greatly impaired by the weakening of positive interactions that results from the loss of phenological overlap.
BibTeX:
@article{revilla_etal-oikos15,
  author = {Revilla, T. A. and Encinas-Viso, F. and Loreau, M.},
  title = {Robustness of plant-pollinator networks under phenological change and habitat destruction},
  journal = {Oikos},
  year = {2015},
  volume = {124},
  number = {1},
  pages = {22--32},
  doi = {http://dx.doi.org/10.1111/oik.01532}
}
Encinas-Viso, F., Revilla, T.A. & Etienne, R.S. (2014), "Shifts in pollinator population structure may jeopardize pollination service", Journal of Theoretical Biology. Vol. 352, pp. 24-30.
Abstract: Plant-pollinator interactions are among the best known and ubiquitous plant-animal mutualisms and are crucial for ecosystem functioning and the maintenance of biodiversity. Most pollinators are insects with several life-stages (e.g. egg, larva, pupa, adult) and the mutualistic interaction depends on the pollinator surviving these different life-stages. However, to our knowledge, pollinator population structure has been ignored in most theoretical models of plant-pollinator dynamics, and we lack understanding of the role of different life-stages in determining the stability of the mutualism. Here we therefore develop a simple plant-pollinator model with a facultative plant and an obligate pollinator with stage-structure. Our model predicts a globally stable equilibrium when pollinator demography is dominated by adults and a locally stable equilibrium when the plants are strongly dependent on pollination and pollinator demography is dominated by the larval stage. In the latter case, the mutualism is vulnerable to fluctuations in the pollinator population size or structure caused by external factors (e.g. pesticides) reducing larval development and increasing adult mortality. This may cause a sudden collapse rather than gradual decrease of the mutualism, after which the pollination service cannot be recovered by reducing these detrimental external factors, but must be accompanied by large increases in pollinator populations. This highlights the importance of considering population structure in plant-pollinator interactions.
BibTeX:
@article{encinas-viso_etal-jtb14,
  author = {Encinas-Viso, F. and Revilla, T. A. and Etienne, R. S.},
  title = {Shifts in pollinator population structure may jeopardize pollination service},
  journal = {Journal of Theoretical Biology},
  year = {2014}
  volume = {352},
  pages = {24--30},
  doi = {http://dx.doi.org/10.1016/j.jtbi.2014.02.030}
}
Encinas-Viso, F., Revilla, T.A., van Velzen, E. & Etienne, R.S. (2014), "Frugivores and cheap fruits make fruiting fruitful", Journal of Evolutionary Biology. Vol. 27(2), pp. 313-324.
Abstract: Animal seed dispersal provides an important ecosystem service by strongly benefiting plant communities. There are several theoretical studies on the ecology of plant-animal seed-disperser interactions, but few studies have explored the evolution of this mutualism. Moreover, these studies ignore plant life-history and frugivore foraging behavior. Thus, it remains an open question what the conditions for the diversification of fruit traits are, in spite of the multitude of empirical studies on fruit trait diversity. Here we study the evolution of fruit traits using a spatially-explicit individual-based model, which considers the costs associated with adaptations inducing dispersal by frugivory, as well as frugivore foraging behavior and abundance. Our model predicts that these costs are the main determinants of the evolution of fruit traits, and that when the costs are not very high, the evolution of larger fruit traits (e.g. fleshy/colorful fruits) is controlled by the choosiness and response thresholds of the frugivores as well as their numerical abundance.
BibTeX:
@article{encinas_etal-jeb14,
  author = {Encinas-Viso, F. and Revilla, T. A. and van Velzen, E. and Etienne, R. S.},
  title = {Frugivores and cheap fruits make fruiting fruitful},
  journal = {Journal of Evolutionary Biology},
  year = {2014},
  volume = {27},
  number = {2},
  pages = {865--877},
  doi = {http://dx.doi.org/10.1111/jeb.12301}
}
Revilla, T.A., Encinas-Viso, F. & Loreau, M. (2014), "(A bit) Earlier or later is always better: Phenological shifts in consumer-resource interactions", Theoretical Ecology. Vol. 7(2), pp. 149-162.
Abstract: Phenology is a crucial life-history trait for species interactions and it can have great repercussions on the persistence of communities and ecosystems. Changes in phenology caused by climate change can disrupt species interactions causing decreases in consumer growth rates, as suggested by the Match Mismatch Hypothesis (MMH). However, it is still not clear what the long-term consequences of such phenological changes are. In this paper we present models in which phenology and consumer-resource feedbacks determine long-term community dynamics. Our results show that consumer viability is constrained by limits in the amount of phenological mismatch with their resources, in accordance with the MMH. But the effects of phenological shifts are often non-monotonic. Consumers generally have higher abundances when they recruit some time before or after their resources because this reduces the long-term effects of overexploitation that would otherwise occur under closer synchrony. Changes in the duration of recruitment phenologies also have important impacts on community stability, with shorter phenologies promoting oscillations and cycles. For small community modules, the effects of phenological shifts on populations can be explained, to a great extent, as superpositions of their effects on consumer-resource pairs. We highlight that consumer-resource feedbacks and overexploitation, which are not typically considered in phenological models, are important factors shaping the long-term responses to phenological changes caused by climate change.
BibTeX:
@article{revilla_etal-theorecol13,
  author = {Revilla, T. A. and Encinas-Viso, F. and Loreau, M.},
  title = {(A bit) Earlier or later is always better: Phenological shifts in consumer-resource interactions},
  journal = {Theoretical Ecology},
  year = {2014},
  volume = {7},
  number = {2},
  pages = {149-162},
  doi = {http://dx.doi.org/10.1007/s12080-013-0207-3}
}
Encinas-Viso, F., Revilla, T.A. & Etienne, R.S. (2012), "Phenology drives mutualistic network structure and diversity", Ecology Letters. Vol. 15(3), pp. 198-208.
Abstract: Several network properties have been identified as determinants of the stability and complexity of mutualistic networks. However, it is unclear which mechanisms give rise to these network properties. Phenology seems important, because it shapes the topology of mutualistic networks, but its effects on the dynamics of mutualistic networks have scarcely been studied. Here, we study these effects with a general dynamical model of mutualistic and competitive interactions where the interaction strength depends on the temporal overlap between species resulting from their phenologies. We find a negative complexity-stability relationship, where phenologies maximising mutualistic interactions and minimising intraguild competitive interactions generate speciose, nested and poorly connected networks with moderate asymmetry and low resilience. Moreover, lengthening the season increases diversity and resilience. This highlights the fragility of real mutualistic communities with short seasons (e.g. Arctic environments) to drastic environmental changes.
BibTeX:
@article{encinas_etal-ecolett12,
  author = {Encinas-Viso, F. and Revilla, T. A. and Etienne, R. S.},
  title = {Phenology drives mutualistic network structure and diversity},
  journal = {Ecology Letters},
  year = {2012},
  volume = {15},
  number = {3},
  pages = {198--208},
  doi = {http://dx.doi.org/10.1111/j.1461-0248.2011.01726.x}
}
Revilla, T.A., Veen, G.F., M.B. Eppinga, M.B. & Weissing, F.J. (2012), "Plant-soil feedbacks and the coexistence of competing plants", Theoretical Ecology. Vol. 6(2), pp. 99-113.
Abstract: Plant-soil feedbacks can have important implications for the interactions among plants. Understanding these effects is a major challenge since it is inherently difficult to measure and manipulate highly diverse soil communities. Mathematical models may advance this understanding by making the interplay of the various processes affecting plant-soil interaction explicit and by quantifying the relative importance of the factors involved. The aim of this paper is to provide a complete analysis of a pioneering plant-soil feedback model developed by Bever and colleagues (J Ecol 85: 561-573, 1997; Ecol Lett 2: 52-62, 1999; New Phytol 157: 465-473, 2003) to fully understand the range of possible impacts of plant-soil feedbacks on plant communities within this framework. We analyze this model by means of a new graphical method that provides a complete classification of the potential effects of soil communities on plant competition. Due to the graphical character of the method, the results are relatively easy to obtain and understand. We show that plant diversity depends crucially on two key parameters that may be viewed as measures of the intensity of plant competition and the direction and strength of plant-soil feedback, respectively. Our analysis provides a formal underpinning of earlier claims that plant-soil feedbacks, especially when they are negative, may enhance the diversity of plant communities. In particular, negative plant-soil feedbacks can enhance the range of plant coexistence by inducing competitive oscillations. However, these oscillations can also destabilize plant coexistence, leading to low population densities and extinctions. In addition, positive feedbacks can allow locally stable forms of plant coexistence by inducing alternative stable states. Our findings highlight that the inclusion of plant-soil interactions may fundamentally alter the predictions on the structure and functioning of above-ground ecosystems. The scenarios presented in this study can be used to formulate hypotheses about the ways soil community effects may influence plant competition that can be tested with empirical studies. This will advance our understanding of the role of plant-soil feedback in ecological communities.
BibTeX:
@article{revilla_etal-theorecol12,
  author = {Revilla, T. A. and Veen, G. F. and M. B. Eppinga, M. B. and Weissing, F. J.},
  title = {Plant-soil feedbacks and the coexistence of competing plants},
  journal = {Theoretical Ecology},
  year = {2012},
  volume = {6},
  number = {2},
  pages = {99-113},
  doi = {http://dx.doi.org/10.1007/s12080-012-0163-3}
}
Revilla, T.A. & Weissing, F.J. (2008), "Nonequilibrium coexistence in a competition model with nutrient storage", Ecology. Vol. 89(3), pp. 865-877.
Abstract: Resource competition theory predicts that, in equilibrium, the number of coexisting species cannot exceed the number of limiting resources. In some competition models, however, competitive interactions may result in nonequilibrium dynamics, allowing the coexistence of many species on few resources. The relevance of these findings is still unclear, since some assumptions of the underlying models are unrealistic. Most importantly, these models assume that individual growth directly reflects the availability of external resources, whereas real organisms can store resources, thereby decoupling their growth from external fluctuations. Here we study the effects of resource storage by extending the well-known Droop model to the context of multiple species and multiple resources. We demonstrate that the extended Droop model shows virtually the same complex dynamics as models without storage. Depending on the model parameters, one may obtain competitive exclusion, stable equilibrium coexistence, periodic and non-periodic oscillations, and chaos. Again, nonequilibrium dynamics allows for the coexistence of many species on few resources. We discuss our findings in the light of earlier work on resource competition, highlighting the role of luxury consumption, trade-offs in competitive abilities, and ecological stoichiometry.
BibTeX:
@article{revilla_weissing-ecology08,
  author = {Revilla, T. A. and Weissing, F. J.},
  title = {Nonequilibrium coexistence in a competition model with nutrient storage},
  journal = {Ecology},
  year = {2008},
  volume = {89},
  number = {3},
  pages = {865-877},
  doi = {http://dx.doi.org/10.1890/07-1103.1}
}
Chaves, L.F., Hernandez, M.J., Revilla, T.A., Rodríguez, D.J. & Rabinovich, J.E. (2004), "Mortality profiles of Rhodnius prolixus (Heteroptera: Reduviidae), vector of Chagas disease", Acta Tropica. Vol. 92(2), pp. 119-125.
Abstract: Life table data of Rhodnius prolixus (Heteroptera: Reduviidae) kept at laboratory conditions were analysed in search for mortality patterns. Gompertz and Weibull mortality models seem adequate to explain the sigmoid shape of the survivorship curve. A significant fit was obtained with both models for females (R^2 = 0.70, P < 0.0005 for the Gompertz model; R^2 = 0.78, P < 0.0005 for the Weibull model) and for males (R^2 = 0.39, P < 0.0005 for the Gompertz model; R^2 = 0.48, P < 0.0005 for the Weibull model). The mortality parameter (b) is higher for females in Gompertz and Weibull models, using smoothed and non-smoothed data (P < 0.05), revealing a significant sex mortality differential. Given the particular life history of this insect, the non-linear relationship between the force of mortality and age may have an important impact in the vectorial capacity of R. prolixus as Chagas disease vector, and its consideration should be included as an important factor in the transmission of Trypanosoma cruzi by triatomines.
BibTeX:
@article{chaves_etal-actatrop02,
  author = {Chaves, L. F. and Hernandez, M. J. and Revilla, T. A. and Rodríguez, D. J. and Rabinovich, J. E.},
  title = {Mortality profiles of Rhodnius prolixus (Heteroptera: Reduviidae), vector of Chagas disease},
  journal = {Acta Tropica},
  year = {2004},
  volume = {92},
  number = {2},
  pages = {119-125},
  doi = {http://dx.doi.org/10.1016/j.actatropica.2004.06.005}
}
Revilla, T.A. & García-Ramos, G. (2003), "Fighting a virus with a virus: a dynamic model for HIV-1 therapy", Mathematical Biosciences. Vol. 185(2), pp. 191-203.
Abstract: A mathematical model examined a potential therapy for controlling viral infections using genetically modified viruses. The control of the infection is an indirect effect of the selective elimination by an engineered virus of infected cells that are the source of the pathogens. Therefore, this engineered virus could greatly compensate for a dysfunctional immune system compromised by AIDS. In vitro studies using engineered viruses have been shown to decrease the HIV-1 load about 1000-fold. However, the efficacy of this potential treatment for reducing the viral load in AIDS patients is unknown. The present model studied the interactions among the HIV-1 virus, its main host cell (activated CD4+ T cells), and a therapeutic engineered virus in an in vivo context; and it examined the conditions for controlling the pathogen. This model predicted a significant drop in the HIV-1 load, but the treatment does not eradicate HIV. A basic estimation using a currently engineered virus indicated an HIV-1 load reduction of 92% and a recovery of host cells to 17% of their normal level. Greater success (98% HIV reduction, 44% host cells recovery) is expected as more competent engineered viruses are designed. These results suggest that therapy using viruses could be an alternative to extend the survival of AIDS patients.
BibTeX:
@article{revilla_garcia-mathbios03,
  author = {Revilla, T. A. and García-Ramos, G.},
  title = {Fighting a virus with a virus: a dynamic model for HIV-1 therapy},
  journal = {Mathematical Biosciences},
  year = {2003},
  volume = {185},
  number = {2},
  pages = {191-203},
  doi = {http://dx.doi.org/10.1016/S0025-5564(03)00091-9}
}
Revilla, T.A. (2002), "Effects of Intraguild Predation on Resource Competition", Journal of Theoretical Biology. Vol. 214(1), pp. 49-62.
Abstract: In this work, a simple Lotka-Volterra model of intraguild predation with three species is analysed, searching for the effect of the top predator on the coexistence with its prey-competitor species. Apart from the well-known result that the intraguild prey must be superior in the competition for the shared prey in order to make coexistence possible, the magnitude of intraguild predation and the form by which the intraguild predator makes use of the intraguild prey have important consequences upon the dynamics, extending or restricting the possibilities of coexistence. These results are easily obtained by nullcline analysis. Also, some interesting results are obtained for the same model but including saturating functional response.
BibTeX:
@article{revilla-jtb02,
  author = {Revilla, T. A.},
  title = {Effects of Intraguild Predation on Resource Competition},
  journal = {Journal of Theoretical Biology},
  year = {2002},
  volume = {214},
  number = {1},
  pages = {49-62},
  doi = {http://dx.doi.org/10.1006/jtbi.2001.2448}
}
Revilla, T.A. (2000), "Resource Competition in Stage-structured Populations", Journal of Theoretical Biology. Vol. 204(2), pp. 289-298.
Abstract: Two models are made to account for the dynamics of a consumer-resource system in which the consumers are divided into juveniles and adults. The resource grows logistically and a type II functional response is assumed for consumers. Resource levels determine fecundity and maturation rates in one model, and mortality rates in the other. The analysis of the models shows that the condition for establishment of consumers is that the product of per capita fecundity rate and maturation rates is higher than the product of juvenile and adult per capita decay rates at a resource level equal to its carrying capacity. This result imposes a minimal abundance of resource able to maintain the consumers. A second result shows an equilibrium stage structure, with a small instability when juveniles and adults mean saturation constants are different. The implications of these results for community dynamics are discussed.
BibTeX:
@article{revilla-jtb00,
  author = {Revilla, T. A.},
  title = {Resource Competition in Stage-structured Populations},
  journal = {Journal of Theoretical Biology},
  year = {2000},
  volume = {204},
  number = {2},
  pages = {289-298},
  doi = {http://dx.doi.org/10.1006/jtbi.2000.2017}
}
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Other publications

Revilla, T.A. & Encinas-Viso, F. (2015), "Ecología y evolución de la endozoocoria", In Modelos y Simulaciones Biológicas: Ecología y Evolución. Cipriani, R. & de Vladar, H. (ed.). Createspace, ISBN: 978-1516867561, 1516867564.
Abstract: En muchas ocasiones la interacción entre plantas y animales puede conducir a un mutualismo: el animal obtiene energía mientras que la planta recibe los beneficios ecológicos de la dispersión. La zoocoria, el proceso de dispersión por agentes animales, es muy importante para el mantenimiento de la viabilidad las poblaciones de plantas. Una de las formas mas conspicuas de zoocoria es la endozoocoria, es decir, la dispersión por parte de animales que consumen propágulos vegetales (e.g. frugívoros). En este trabajo construimos un modelo dinámico que considera varios aspectos esenciales de la endozoocoria. Con este modelo, encontramos que la supervivencia de las semillas a la frugivoría tiene una influencia desproporcionadamente grande sobre la abundancia vegetal. También concluimos que los factores de regulación denso-dependientes hacen que los beneficios de la endozoocoria sean limitados. Tomando en consideración que las adaptaciones para la endozoocoria involucran costos para la planta, usamos nuestro modelo para estudiar la evolución de rasgos destinados a atraer animales. En condiciones de selección denso-independiente encontramos que la endozoocoria tiende a ser desfavorable si los costos involucrados son altos, mientras que para condiciones denso-dependientes esta tiende a ser favorable incluso si los costos son altos. Finalmente, concluimos que el balance apropiado entre factores de mortalidad denso-independientes vs denso-dependientes, y la fisiología sensorial de los animales, puede contribuir a la diversificación evolutiva de la endozoocoria.
BibTeX:
@incollection{revillaencinas2014,
  author = {Revilla, T. A. and Encinas-Viso, F.},
  title = {Ecología y Evolución de la Endozoocoria},
  booktitle = {Modelos y Simulaciones Biológicas: Ecología y Evolución},
  Publisher = {Createspace. ISBN: 978-1516867561, 1516867564},
  Year = {2015},
  Editor = {Cipriani, R. and de Vladar, H.P.}
  url = {https://www.parmenides-foundation.org/publication/publication-details/ModSimBioEE/}
}
Revilla, T.A. (2010), "Multispecies Resource Competition". PhD Thesis: University of Groningen.
Abstract: The main focus of this thesis is the study of competition for resources among many species, from a theoretical position. This is accomplished using the "nutrient storage model" of algal competition. This model is of considerable relevance in plankton ecology and in the field of ecological stoichiometry. Unfortunately, previous research considered just a few species in contrast with the hundreds that are present in real communities. Thanks to analytical and numerical approaches, we can conclude that multispecies competition models with nutrient storage display a rich and complicated dynamics including oscillations, chaos and the coexistence of many species on few resources. To a great extent, the different dynamics are the consequence of specific trade-offs in the species consumption policies, which is also the case for less realistic models of resource competition. In addition, the comparison with other models reveal that there are general rules governing the multispecies dynamics, and such rules are independent of the underlying mechanisms. This robustness is good news for a niche based perspective of community ecology, in which diversity is the consequence of the species properties. However, the addition of more mechanistic detail, like the introduction of nutrient storage, reveals that predictability becomes rather difficult, not to say pointless, because very small variation in biological parameters or initial conditions can lead to equilibrium coexistence, nonequilibrium coexistence, chaotic dynamics, or competitive exclusion. The implication of these contrasting results is that competitive communities may behave in a consistent way from a statistical perspective, but not in a case by case basis.
BibTeX:
@phdthesis{mythesis2010,
  author = {Revilla, T. A.},
  title = {Multispecies Resource Competition},
  school = {University of Groningen},
  year = {2010},
}
Revilla, T.A. (2013), "Changement climatique: synchronisation des espèces et modélisation", In Ariège, terre de science, Collection Petit Illustré. (19), pp. 16. La Dépêche du Midi / CNRS.
Abstract: L'étude des variations que les climats font subir aux différenres espèces végétales et animales permet de mieux comprendre les conséquences de ces changements.
BibTeX:
@incollection{revilla-depeche13,
  author = {Revilla, T. A.},
  title = {Changement climatique: synchronisation des espèces et modélisation},
  booktitle = {Ariège, terre de science, Collection Petit Illustré},
  publisher = {La Dépêche du Midi / CNRS},
  year = {2013},
  number = {19},
  pages = {16},
  url = {http://www.ladepeche.fr/article/2013/10/09/1726476-foix-ariege-terre-de-sciences.html}
}
Arnoldi, J-F., Haegeman, B., Revilla, T.A. & Loreau, M. (2016), "Particularity of 'Universal resilience patterns in complex networks'" , BioRxiv:056218.
Abstract: In a recent Letter to Nature, Gao, Barzel and Barabási describe an elegant procedure to reduce the dimensionality of complex dynamical networks, which they claim reveals "universal patterns of network resilience", offering "ways to prevent the collapse of ecological, biological or economic systems, and guiding the design of technological systems resilient to both internal failures and environmental changes". However, Gao et al restrict their attention to systems for which all interactions between nodes are mutualistic. Since antagonism is ubiquitous in natural and social networks, we clarify why this stringent hypothesis is necessary and what happens when it is relaxed. By analysing broad classes of competitive and predator-prey networks we provide novel insights into the underlying mechanisms at work in Gao et al's theory, and novel predictions for dynamical systems that are not purely mutualistic.
BibTeX:
@article{Arnoldi056218,
  author = {Arnoldi, Jean-Fran{\c c}ois and Haegeman, Bart and Revilla, Tom{\'a}s and Loreau, Michel},
  title = {Particularity of {\textquotedblleft}Universal resilience patterns in complex networks{\textquotedblright}},
  year = {2016},
  doi = {10.1101/056218},
  publisher = {Cold Spring Harbor Labs Journals},
  URL = {http://biorxiv.org/content/early/2016/05/31/056218},
  eprint = {http://biorxiv.org/content/early/2016/05/31/056218.full.pdf},
  journal = {bioRxiv}
}
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