Panagiotis Theodorou

Dr. Panagiotis Theodorou

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Research Focus & Metrics

Academic Career Length

15Years (2012-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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29 January 2020 in Nature Communications
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PTPanagiotis Theodorou
Panagiotis Theodorou
RRRita Radzevičiūtė
Rita Radzevičiūtė
GLGuillaume Lentendu
Guillaume Lentendu
BKBelinda Kahnt
Belinda Kahnt
MHMartin Husemann
Martin Husemann
RPRobert John Paxton
Robert John Paxton
Urbanisation is an important global driver of biodiversity change, negatively impacting some species groups whilst providing opportunities for others. Yet its impact on ecosystem services is poorly investigated. Here, using a replicated experimental design, we test how Central European cities impact flying insects and the ecosystem service of pollination. City sites have lower insect species richness, particularly of Diptera and Lepidoptera, than neighbouring rural sites. In contrast, Hymenoptera, especially bees, show higher species richness and flower visitation rates in cities, where our experimentally derived measure of pollination is correspondingly higher. As well as revealing facets of biodiversity (e.g. phylogenetic diversity) that correlate well with pollination, we also find that ecotones in insect-friendly green cover surrounding both urban and rural sites boost pollination. Appropriately managed cities could enhance the conservation of Hymenoptera and thereby act as hotspots for pollination services that bees provide to wild flowers and crops grown in urban settings.

3 March 2015 in Journal of Animal Ecology
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DMDino P. McMahon
Dino P. McMahon
MFMatthias A Fürst
Matthias A Fürst
JCJesicca Caspar
Jesicca Caspar
PTPanagiotis Theodorou
Panagiotis Theodorou
MBMark J F Brown
Mark J F Brown
RPRobert John Paxton
Robert John Paxton
Summary: Declining populations of bee pollinators are a cause of concern, with major repercussions for biodiversity loss and food security.RNAviruses associated with honeybees represent a potential threat to other insect pollinators, but the extent of this threat is poorly understood. This study aims to attain a detailed understanding of the current and ongoing risk of emerging infectious disease (EID) transmission between managed and wild pollinator species across a wide range ofRNAviruses. Within a structured large‐scale national survey across 26 independent sites, we quantify the prevalence and pathogen loads of multipleRNAviruses in co‐occurring managed honeybee (Apis mellifera) and wild bumblebee (Bombusspp.) populations. We then construct models that compare virus prevalence between wild and managed pollinators. MultipleRNAviruses associated with honeybees are widespread in sympatric wild bumblebee populations. Virus prevalence in honeybees is a significant predictor of virus prevalence in bumblebees, but we remain cautious in speculating over the principle direction of pathogen transmission. We demonstrate species‐specific differences in prevalence, indicating significant variation in disease susceptibility or tolerance. Pathogen loads within individual bumblebees may be high and in the case of at least oneRNAvirus, prevalence is higher in wild bumblebees than in managed honeybee populations. Our findings indicate widespread transmission ofRNAviruses between managed and wild bee pollinators, pointing to an interconnected network of potential disease pressures within and among pollinator species. In the context of the biodiversity crisis, our study emphasizes the importance of targeting a wide range of pathogens and defining host associations when considering potential drivers of population decline.

12 November 2018 in Evolutionary Applications
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LRL. Ruth Rivkin
L. Ruth Rivkin
JSJames S. Santangelo
James S. Santangelo
MAMarina Alberti
Marina Alberti
MAMyla F. J. Aronson
Myla F. J. Aronson
CKCharlotte W. de Keyzer
Charlotte W. de Keyzer
MJMarc T. J. Johnson
Marc T. J. Johnson
Urban ecosystems are rapidly expanding throughout the world, but how urban growth affects the evolutionary ecology of species living in urban areas remains largely unknown. Urban ecology has advanced our understanding of how the development of cities and towns change environmental conditions and alter ecological processes and patterns. However, despite decades of research in urban ecology, the extent to which urbanization influences evolutionary and eco‐evolutionary change has received little attention. The nascent field of urban evolutionary ecology seeks to understand how urbanization affects the evolution of populations, and how those evolutionary changes in turn influence the ecological dynamics of populations, communities, and ecosystems. Following a brief history of this emerging field, this Perspective article provides a research agenda and roadmap for future research aimed at advancing our understanding of the interplay between ecology and evolution of urban‐dwelling organisms. We identify six key questions that, if addressed, would significantly increase our understanding of how urbanization influences evolutionary processes. These questions consider how urbanization affects nonadaptive evolution, natural selection, and convergent evolution, in addition to the role of urban environmental heterogeneity on species evolution, and the roles of phenotypic plasticity versus adaptation on species’ abundance in cities. Our final question examines the impact of urbanization on evolutionary diversification. For each of these six questions, we suggest avenues for future research that will help advance the field of urban evolutionary ecology. Lastly, we highlight the importance of integrating urban evolutionary ecology into urban planning, conservation practice, pest management, and public engagement.

18 March 2022 in Science
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JSJames S. Santangelo
James S. Santangelo
RNRob W. Ness
Rob W. Ness
BCBeata Cohan
Beata Cohan
CFConnor R. Fitzpatrick
Connor R. Fitzpatrick
SISimon G. Innes
Simon G. Innes
MJMarc T. J. Johnson
Marc T. J. Johnson
Urbanization transforms environments in ways that alter biological evolution. We examined whether urban environmental change drives parallel evolution by sampling 110,019 white clover plants from 6169 populations in 160 cities globally. Plants were assayed for a Mendelian antiherbivore defense that also affects tolerance to abiotic stressors. Urban-rural gradients were associated with the evolution of clines in defense in 47% of cities throughout the world. Variation in the strength of clines was explained by environmental changes in drought stress and vegetation cover that varied among cities. Sequencing 2074 genomes from 26 cities revealed that the evolution of urban-rural clines was best explained by adaptive evolution, but the degree of parallel adaptation varied among cities. Our results demonstrate that urbanization leads to adaptation at a global scale.

28 April 2022 in Current Opinion in Insect Science
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Journal Article
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PTPanagiotis Theodorou
Panagiotis Theodorou
Cities are expanding worldwide and urbanisation is considered a global threat to biodiversity. Urban ecology has provided important insights on how urban environmental changes might affect individuals, populations, and species; however, we know little about how the ecological impacts of urbanisation alter species interactions. Species interactions are the backbone of ecological communities and play a crucial role in population and community dynamics and in the generation, maintenance and structure of biodiversity. Here, I review urban ecological studies to identify key mechanistic pathways through which urban environmental processes could alter antagonistic and mutualistic interactions among species. More specifically, I focus on insect predation, parasitoidism and herbivory, competition, insect host-pathogen interactions, and pollination. I furthermore identify important knowledge gaps that require additional research attention and I suggest future research directions that may help to shed light on the mechanisms that affect species interactions and structure insect communities and will thus aid conservation management in cities.

22 June 2023 in Ecology Letters
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HLHuan Liang
Huan Liang
YHYong‐Deng He
Yong‐Deng He
PTPanagiotis Theodorou
Panagiotis Theodorou
CYChun-Feng Yang
Chun-Feng Yang
Urbanization is increasing worldwide, with major impacts on biodiversity, species interactions and ecosystem functioning. Pollination is an ecosystem function vital for terrestrial ecosystems and food security; however, the processes underlying the patterns of pollinator diversity and the ecosystem services they provide in cities have seldom been quantified. Here, we perform a comprehensive meta‐analysis of 133 studies examining the effects of urbanization on pollinators and pollination. Our results confirm the widespread negative impacts of urbanization on pollinator richness and abundance, with Lepidoptera being the most affected group. Furthermore, pollinator responses were found to be trait‐specific, with below‐ground nesting and solitary Hymenoptera, and spring flyers more severely affected by urbanization. Meanwhile, cities promote non‐native pollinators, which may exacerbate conservation risks to native species. Surprisingly, despite the negative effects of urbanization on pollinator diversity, pollination service measured as seed set is enhanced in non‐tropical cities likely due to abundant generalists and managed pollinators therein. We emphasize that the richness of local flowering plants could mitigate the negative impacts of urbanization on pollinator diversity. Overall, the results demonstrate the varying magnitudes of multiple moderators on urban pollinators and pollination services and could help guide conservation actions for biodiversity and ecosystem function for a sustainable future.