Network Connectance Research Articles

Professor Alessandro Zuddas' Impact and Legacy: The Influential Networking and Human Connection Skills of a Passionate Scientist, Clinical Academic, and Pioneer in Child and Adolescent Psychopharmacology.

Professor Alessandro Zuddas, from the University of Cagliari (Italy), passed away prematurely in July 2022. As a prominent figure in child and adolescent neuropsychiatry, he substantially influenced the fields of neurodevelopmental disorders and neuropsychopharmacology both nationally and internationally. Professor Zuddas was a renowned expert in basic and clinical research in child and adolescent psychopharmacology, an enlightened and stimulating educator, and a mentor to many students, residents, and senior colleagues. With his enthusiasm and unique ability to network, he contributed enormously to trace a path in the field that we continue to follow. His name will remain in the textbooks and articles he authored. Here, as colleagues and friends who had the honor to work with him, we provide our personal views of Alessandro's impact and legacy, which go far beyond his publications.

Multiple stressors drive multitrophic biodiversity and ecological network dynamics in a shrinking sandy lake

Stressors endanger lake ecosystem biodiversity and networks, especially in sandy lakes of arid/semiarid regions, where impacts are poorly understood. Here, we investigate the changes in multitrophic biodiversity and ecological networks under increasing stress (temperature, nutrients, lake area) by using sedimentary DNA from a shrinking sandy lake in China over nearly 100 years. With increasing stress, species richness and stability increased, whereas species turnover decreased. Species synchronism decreased at high-trophic levels but increased at low-trophic levels. Empirical dynamic modeling showed network connectance and strength of species interactions decreased–increased–decreased over time, signaling a potential adaption–resistance–degradation change in ecosystem responses with increasing stress. Models also indicated network structure primarily depended on direct effects of nutrients and temperature under low/medium stress and on a diversity-mediated pathway under high stress. Thus, maintaining ecological network structure complexity and integrity in lake ecosystems is essential to mitigate the effects of multiple stresses.

Persistent biological invasions alter ecological network topology, impacting disease transmission during community assembly

Ecological networks experiencing persistent biological invasions may exhibit distinct topological properties, complicating the understanding of how network topology affects disease transmission during invasion-driven community assembly. We developed a trait-based network model to assess the impact of network topology on disease transmission, measured as community- and species-level disease prevalence. We found that trait-based feeding interactions between host species determine the frequency distribution of the niche of co-occurring species in steady-state communities, being either bimodal or multimodal. The width of the growth kernel influences the degree-biomass relationship of species, being either weakly positive or strongly negative. When this relationship is weakly positive, species-level disease prevalence is primarily correlated with biomass. However, when the degree-biomass relationship is strongly negative, species-level disease prevalence is determined by the difference between a host species’ in-degree and out-degree closeness centrality. At the community level, disease prevalence is generally amplified by increasing host richness, community biomass, and the standard deviation of interaction generality, while it is diluted by higher network connectance. Our framework verifies the amplification effects of host richness during invasion-driven community assembly and offers valuable insights for estimating disease prevalence based on host network topology.

Symposium 1: Analyzing Special Needs Support through Networks and Learning Analytics in Primary Education

In this short paper, analytical issues of networked learning are related to special needs support and learning analytics research in primary education. Very brief suggestions for these analytical issues are discussed for the networked learning research field to continue to expand upon. In part, the discussion is intended to form the underpinnings of a work-in-progress research project with cross-disciplinary networked connections across multiple universities. Currently, teachers are faced with an expansion of their professional role that may be too economically demanding, which may result in consequences that is not beneficial for children with special needs. Researchers that aim to study inclusive education face the challenge to represent findings in a way that does not increase workload for teachers in primary education. Any failings in this regard may strengthen the intertwining of educational results and economical interest, which to a large extent could be considered as opposed to networked learning theory, dualistically separated from pedagogical concerns. The inclusive goal of addressing diversity for children with special needs may be promoted by providing an educational setting with networked connections that enhances variation to modes of behavior, by addressing specific and contextual strengths and challenges of students appropriately. With learning analytics, specific and contextual strengths and challenges of students might be easier to highlight with new database schemas, algorithms, and user interfaces to represent networked data. Radical behaviorist methodology may further emphasize specific contextual findings from primary education through strictly defined events of behavior, which may be of interest to the networked learning research community to further expand upon. Thus, this paper proposes suggestions for networked learning research of primary education, with approaches commonly implemented in special education, such as radical behaviorist methodology. The suggestions are based on networked consequences from three social dimensions: political, economic, and technology-developmental. 1 The political dimension is discussed through the notion of inclusive education for children with special needs and its current state, 2 the economic dimension is discussed through the 21st century role expansion of teachers, 3 the technology-developmental dimension is discussed through learning analytic research and its connection to bodily and biological associations. This dimension is especially noteworthy, as learning analytics is currently underutilized in primary education research as opposed to common higher education research.

Seed-Bird co-occurrence networks in cocoa agroforests: Morphological matching analysis reveals shading effects on network organization

Tropical forests are highly vulnerable to ongoing deforestation, which often involves converting land for agricultural use. While tropical agroforests have been promoted as wildlife-friendly systems, limited information is available on the ability of agroforests to provide diverse fruits that attract birds and thus contribute to essential ecological processes, such as seed dispersal. Here, we evaluated the organization of tropical seed-bird co-occurrence networks in cocoa agroforests of the Brazilian Atlantic Forest. Specifically, we investigated the influence of (i) landscape and local predictors in shaping the structure of seed-bird co-occurrence networks; and (ii) species traits in explaining their interactive role in the networks. We constructed matrices of presence-absence interactions based on morphological matching among the beak width of frugivorous bird species and the size of ornithochorous seed species (both native and exotic species), using field data of seed rain and understory bird surveys from 15 cocoa agroforests. We further evaluated both the effects of landscape forest cover and local shading on five network indices and how functional traits of birds and seeds explain their importance to the network. In total, we obtained 467 events of potential plant-bird interactions, which revealed a modular pattern. We also observed that only canopy shading significantly affected network connectance, and seed diameter was a significant predictor in explaining tree species contribution in the network. Therefore, our findings show that cocoa agroforests with greater shading will have greater opportunities for interactions between frugivorous birds and plants. We also observed that plants with small seeds play a more relevant role in the co-occurrence interaction network. Based on findings, we emphasized that cocoa agroforests likely maintain certain mutualistic relationships to ensure ecosystem functionality and demonstrate that co-occurrence networks have great potential for future seed dispersal networks in agricultural ecosystems.

Food-web complexity, consumer behavior, and diet specialism: impacts on ecosystem stability

AbstractEcological stability is a fundamental aspect of food web dynamics. In this study, we explore the factors influencing stability in complex ecological networks, characterizing it through biomass oscillations and species persistence. Using an Extended Niche model, we generate diverse food web structures and investigate the effects of intraspecific consumer interference, network size, connectance, and diet specialism on stability. Our findings reveal that intraspecific consumer interference plays a pivotal role in shaping stability. Higher interference results in stable dynamics, reducing oscillations and extinctions. Additionally, differences emerge between food webs comprised of invertebrate consumers and those of ectotherm vertebrates, with the latter showing higher oscillations. Network size and connectance also influence stability, where larger and more connected webs tend to exhibit reduced oscillations. Overall, our study sheds light on the complex interplay of factors affecting ecological stability in food webs. Understanding these dynamics is crucial for biodiversity conservation and ecosystem management.

Interconnection between density-regulation and stability in competitive ecological network

In natural ecosystems, species can be characterized by the nonlinear density-dependent self-regulation of their growth profile. Species of many taxa show a substantial density-dependent reduction for low population size. Nevertheless, many show the opposite trend; density regulation is minimal for small populations and increases significantly when the population size is near the carrying capacity. The theta-logistic growth equation can portray the intraspecific density regulation in the growth profile, theta being the density regulation parameter. In this study, we examine the role of these different growth profiles on the stability of a competitive ecological community with the help of a mathematical model of competitive species interactions. This manuscript deals with the random matrix theory to understand the stability of the classical theta-logistic models of competitive interactions. Our results suggest that having more species with strong density dependence, which self-regulate at low densities, leads to more stable communities. With this, stability also depends on the complexity of the ecological network. Species network connectance (link density) shows a consistent trend of increasing stability, whereas community size (species richness) shows a context-dependent effect. We also interpret our results from the aspect of two different life history strategies: r and K-selection. Our results show that the stability of a competitive network increases with the fraction of r-selected species in the community. Our result is robust, irrespective of different network architectures.

Network Complexity and Stability of Microbes Enhanced by Microplastic Diversity.

Microplastic mixtures are ubiquitously distributed in global ecosystems and include varying types. However, it remains unknown how microplastic diversity affects the biotic interactions of microbes. Here, we developed novel experiments of 600 microcosms with microplastic diversity ranging from 1 to 6 types and examined ecological networks for microbial communities in lake sediments after 2 months of incubation at 15 and 20 °C. We found that microplastic diversity generally enhanced the complexity of microbial networks at both temperatures, such as increasing network connectance and reducing average path length. This phenomenon was further confirmed by strengthened species interactions toward high microplastic diversity except for the negative interactions at 15 °C. Interestingly, increasing temperatures further exaggerated the effects of microplastic diversity on network structures, resulting in higher network connectivity and species interactions. Consistently, using species extinction simulations, we found that higher microplastic diversity and temperature led to more robust networks, and their effects were additionally and positively mediated by the presence of biodegradable microplastics. Our findings provide the first evidence that increasing microplastic diversity could unexpectedly promote the complexity and stability of microbial networks and that future warming could amplify this effect.

The Internet is Relational: Networked Connectivity and the ‘Sovereign Individual’ in Videos by Brenda Lien

This article argues that the Internet is a relational space. It draws on a provocative, multimedia trilogy by German video artist Brenda Lien to analyse the challenges to notions of sovereign subjectivity posed by the digital age. Lien’s Call of … trilogy explores the ambivalences of life on the participatory Internet, deploying at times shocking images of violence to undermine Web 2.0’s appealing aesthetics and cheery injunctions to its users to self-optimize and so gain personal sovereignty. The Internet’s spread in the 1990s into mass consumer use coincided with conservative ideologies aimed at promoting the ‘sovereign individual’ (Dale Davidson and William Rees-Mogg, 2008), capable of profiting in the dotcom era from neoliberal codes of conduct and low regulations. Since then, dataveillance via Internet platforms has grown to reduce technology users’ agency and privacy, framing Internet connectivity as a forcibly relational state, despite the individualist self-optimization opportunities it offers. The article reveals networked connectivity as an ambivalent mode of relationality, both necessary due to the communication and affiliation the Internet makes possible, and worrisome due to the connection it forces between technology users and corporations, unanswerably profiting from human needs in a way that challenges the sovereignty of the networked subject radically.

SELECTION USING ENHANCED NORMAL FORM GAME THEORY BASED OPTIMIZATION APPROACH IN WSN

Heterogeneous network is a network connecting mobile station (MS) with different kinds of wireless network. It will provide an efficient network connection for mobile users. When considering various wireless access technologies, it's difficult to search out reliable criteria to pick out the most effective offered wireless heterogeneous network. . Game theory techniques have been receiving growing attention in recent years as they can be adopted in order to model and understand competitive and cooperative scenarios between rational decision makers.In this paper, our aim is to develop an economical wireless network choice algorithm which is optimized using enhanced Normal Form Optimization Algorithm which follows game theory based procedure . This algorithm is proposed for optimizing the heterogeneous wireless environment comprising universal mobile telecommunication system (UMTS) and long term evaluation (LTE). Further, within optimization algorithm resource allocation is considered as an objective function. The incorporated optimization algorithm is involved in the optimal computation process for reducing channel complexity through optimal solution estimation. The computation complexity of proposed Normal Form Optimization Algorithm with TOPSIS method (NFOA-TOPSIS) measured in terms of running time and network utilization is measured in terms of the Packet Delivery Rate (PDR), throughput, simulation time, end-to-end delay and Power consumption. The simulation results expressed that the proposed NFOA provides reduced running time and increases PDR rather than conventional MADM (i.e., Hybrid Fuzzy Analytic Hierarchy Process (FAHP)& Technique for Order Preference by Similarity to an Ideal Solution -Hybrid FHAP-TOPSIS) method. The reduce in running time implies reduced complexity of proposed scheme. Also, the increase in PDR and throughput leads to reduced end-to-end delay and power consumption resulted in efficient utilization of available channels in heterogeneous networks.

Navigating Challenges to Work-Based Learning Experiences: Responses From Special Educators

A host of challenges have been associated with providing work-based learning experiences (WBLEs) for students with disabilities; however, little is known about how special education teachers navigate or overcome these challenges. The purpose of this qualitative study therefore was to understand how special education teachers respond to the challenges they experience when providing WBLEs for students with extensive support needs. Participants included nine special education teachers who primarily serve 14- to 22-year-old students with extensive support needs. Each teacher participated in one semi-structured interview, and transcripts were analyzed using thematic analysis. Teachers reported responding to challenges by (a) creating authentic school-based work experiences, (b) providing direct support for students and families, (c) networking and building new connections, and (d) advocating for students in school and community contexts. Findings from this study have practical implications for special education teachers who provide WBLEs for students with extensive support needs.

Diversifying agroecological systems: Plant-pollinator network organisation and landscape heterogeneity matter

Agroecology is a process-based agriculture that implements agrobiodiversification to stabilize ecosystem processes and crop yield, leading to sustainable food systems. Traditionally, agrobiodiversification focused on increasing within-farm plant richness, which may increase local species richness of higher trophic levels. However, it is increasingly recognized that stabilizing ecosystem processes involving plant-animal interactions –e.g., pollination- requires practices that consider the organisation of interactions and heterogeneity effects at landscape level. In this work, we investigated how plant-pollinator interactions organised in agricultural landscapes harbouring agroecological farms and how landscape heterogeneity modulated interactions organisation. We characterized the organisation of 36 plant-pollinator networks describing interactions in nine agricultural landscapes -i.e., agroecological farms and their surroundings- across four flowering peak periods in the Agri-food region of central Córdoba, Argentina. We evaluated (1) centrality to network organisation of plant and pollinator only registered interacting in agroecological farms, farm surroundings (unique species) or in both locations (shared species); and (2) network organisation across gradients of landscape configurational (mean edge density) and compositional (forest proportion) heterogeneity. We found that plant-pollinator networks at landscape scale showed nested structures. Shared plant and pollinator species were the less represented in such networks but were central to networks organisation, i.e., they were connected to most species and with the highest frequency. Results also showed that network organisation changed with landscape configurational heterogeneity. Higher landscape mean edge density was associated with higher total and unique plant richness in networks and lower richness of shared plants. Network connectance and nestedness decreased with higher landscape mean edge density, i.e., plant and pollinator species interacted with less species, shared less interaction partners with more specialist species and showed lower interaction frequency with generalist partners in more heterogeneous landscapes. Our study showed that in agricultural landscapes harbouring agroecological farms (1) a few species inhabiting and showing interactions in both agroecological farms and their surroundings are key to the organisation of plant-pollinator interactions, and (2) landscape heterogeneity modulates such organisation. As interaction networks dynamic is influenced by network organisation, landscape configurational heterogeneity may modulate the stability of the pollination process and ultimately agroecological production. Thus, the agrobiodiversification of agroecological systems may benefit from considering the complexity of plant-pollinator interdependencies across agricultural landscapes and the effects of landscape heterogeneity on such complexity.

Exploring Information communication Technology-enabled travel Pattern in a city region of India

ABSTRACTInformation and Communication Technology (ICT) is advocated to contribute to sustainable transportation by prompting a change in travel patterns. Therefore, using an ICT-enabled city region in India as the study context, the objectives of the study were to examine the influence of ICT on travel patterns in city regions and explore the strategies to enhance ICT usage for positively changed travel patterns. Findings suggest that definite linkages between ICT usage and travel patterns exist. An increase in ICT usage in daily activities of people will enable a significant reduction in trip generation, travel distance and travel time. Strategic interventions including enhancing networking and ICT connectivity, provisioning free Wi-Fi hot spots at important nodal points, and enabling the availability of real-time road transportation-related information can enhance ICT usage leading to a positively changed travel pattern. This is likely to improve traffic movement and reduce congestion contributing to sustainable urban road transportation.

Prescribed fire increases plant-pollinator network robustness to losses of rare native forbs.

Restoration efforts often focus on changing the composition and structure of invaded plant communities, with two implicit assumptions: (1) functional interactions with species of other trophic levels, such as pollinators, will reassemble automatically when native plant diversity is restored and (2) restored communities will be more resilient to future stressors. However, the impact of restoration activities on pollinator richness, plant-pollinator interaction network structure, and network robustness is incompletely understood. Leveraging a restoration chronosequence in Pacific Northwest prairies, we examined the effects of restoration-focused prescribed fire and native forb replanting on floral resources, pollinator visitation, and plant-pollinator network structure. We then simulated the effects of plant species loss/removal scenarios on secondary extinction cascades in the networks. Specifically, we explored three management-relevant plant loss scenarios (removal of an abundant exotic forb, removal of an abundant forb designated a noxious weed, and loss of the rarest native forb) and compared them to control scenarios. Pyrodiversity and proportion of area recently burned increased the abundance and diversity of floral resources, with concomitant increases in pollinator visitation and diversity. Pyrodiversity also decreased network connectance and nestedness, increased modularity, and buffered networks against secondary extinction cascades. Rare forbs contributed disproportionately to network robustness in less restored prairies, while removal of typical "problem" plants like exotic and noxious species had relatively small impacts on network robustness, particularly in prairies with a long history of restoration activities. Restoration actions aimed mainly at improving the diversity and abundance of pollinator-provisioning plants may also produce plant-pollinator networks with increased resilience to plant species losses.

Manipulating network connectance by altering plant attractiveness.

Mutualistic interactions between plants and their pollinating insects are critical to the maintenance of biodiversity. However, we have yet to demonstrate that we are able to manage the structural properties of these networks for the purposes of pollinator conservation and preserving functional outcomes, such as pollination services. Our objective was to explore the extent of our ability to experimentally increase, decrease, and maintain connectance, a structural attribute that reflects patterns of insect visitation and foraging preferences. Patterns of connectance relate to the stability and function of ecological networks. We implemented a 2-year field experiment across eight sites in urban Dublin, Ireland, applying four agrochemical treatments to fixed communities of seven flowering plant species in a randomized block design. We spent ~117 h collecting 1,908 flower-visiting insects of 92 species or morphospecies with standardized sampling methods across the 2 years. We hypothesized that the fertilizer treatment would increase, herbicide decrease, and a combination of both maintain the connectance of the network, relative to a control treatment of just water. Our results showed that we were able to successfully increase network connectance with a fertilizer treatment, and maintain network connectance with a combination of fertilizer and herbicide. However, we were not successful in decreasing network connectance with the herbicide treatment. The increase in connectance in the fertilized treatment was due to an increased species richness of visiting insects, rather than changes to their abundance. We also demonstrated that this change was due to an increase in the realized proportion of insect visitor species rather than increased visitation by common, generalist species of floral visitors. Overall, this work suggests that connectance is an attribute of network structure that can be manipulated, with implications for management goals or conservation efforts in these mutualistic communities.

The smart grid archipelago: Infrastructures of networked (dis)connectivity in Amman

This article examines the fragmented connections of Jordan’s smart grid, building on scholarship that questions how smart infrastructures reshape governance, sociospatial exclusion, and the fabric of urban life. Jordan’s ambitious smart energy program is often held up as a global model by investors, as it catalyzed over US$4 billion in private investment for new renewable and smart energy development. Yet smart energy transition is experienced in powerfully uneven ways, as distributed solar installations and smart grid technologies radically remake the spaces of urban life. Rooted in sixteen months of ethnographic fieldwork, this article traces the vertical materialization of the smart grid from the ground up, from in-home smart meters through the evolving interconnections that they enact. I argue that (post)colonial property relations engender an archipelagic landscape of (dis)connectivity that redistributes the benefits and burdens of digitalization. Drawing from Glissant’s archipelagic thought, I examine (dis)connection and urban fragmentation as a form of relation that links enduring (post)colonial relations to contemporary projects of smart development. In the (post)colonial world, as smart infrastructures are built into the conduits of uneven property relations, they come to incorporate not only capitalist logics but also racialized logics and historically contingent relations of exclusion and differentiation.

A Bayesian network perspective on neonatal pneumonia in pregnant women with diabetes mellitus

ObjectiveTo predict the influencing factors of neonatal pneumonia in pregnant women with diabetes mellitus using a Bayesian network model. By examining the intricate network connections between the numerous variables given by Bayesian networks (BN), this study aims to compare the prediction effect of the Bayesian network model and to analyze the influencing factors directly associated to neonatal pneumonia.MethodThrough the structure learning algorithms of BN, Naive Bayesian (NB), Tree Augmented Naive Bayes (TAN), and k-Dependence Bayesian Classifier (KDB), complex networks connecting variables were presented and their predictive abilities were tested. The BN model and three machine learning models computed using the R bnlean package were also compared in the data set.ResultsIn constraint-based algorithms, three algorithms had different presentation DAGs. KDB had a better prediction effect than NB and TAN, and it achieved higher AUC compared with TAN. Among three machine learning modes, Support Vector Machine showed a accuracy rate of 91.04% and 67.88% of precision, which was lower than TAN (92.70%; 72.10%).ConclusionKDB was applicable, and it can detect the dependencies between variables, identify more potential associations and track changes between variables and outcome.

Plant richness and vegetation structure drive the topology of plant-herbivore networks in Neotropical savannas

Plants and phytophagous insects make up the highest terrestrial diversity on the planet, forming complex interspecific interaction networks. Interaction networks are an important tool to understand how ecological interactions shape plant-herbivore assemblages. In the present study, we tested the hypotheses that the plant species richness and vegetation structure (vegetation cover and vegetation height) (i) drive the richness and abundance of herbivorous insects and (ii) determines topological patterns (connectance, specialization and modularity) of plant-herbivore networks. We sampled ten different areas in the Neotropical savannas to assess those hypotheses and constructed plant-herbivore interaction matrices using species composition data. Plant-herbivore interaction networks comprised 298 plants of 60 species, 421 insects distributed in 96 morphospecies, and totalizing 218 interactions. We found that plant species richness positively influenced the species richness of herbivorous insects, whereas average vegetation height negatively affected the species richness of herbivorous insects. The abundance of herbivorous insects was negatively affected by plant species richness, and by vegetation height. Species richness and structure of plant communities also significantly affected network topological parameters. Network connectance was negatively influenced by plant richness and positively affected by vegetation cover. Besides, plant species richness positively influenced network modularity, whereas vegetation height negatively affected network modularity. However, the plant community diversity and vegetation structure did not affect network specialization. Our results show that both plant community diversity and vegetation structure in Neotropical savannas drive the structure of plant-herbivore interaction networks. Considering the current high rates of removal of native vegetation in Brazilian savannas, our findings indicate that the preserving this ecosystem is crucial for maintaining ecosystem services through plant-herbivore interaction networks.

Changing webs—Variation of complex networks over a tidal cycle in an intertidal rocky reef

Incorporating temporal variation in models is one of the most important challenges in food web research. One of the environments where time causes profound changes is the intertidal zone, where the immersion-emersion cycle drastically changes the abiotic and biotic conditions. Intertidal rocky shores have been intensively studied, however the variation in the complex food web network that occurs during a tidal cycle remains undescribed. Highly resolved food web networks were assembled for an intertidal reef depicting the food web during low and high tide, and with and without tide pools. It was concluded that high tide adds new species to the web, but it does not add complexity since network connectance was not changed. This occurs because incoming species are mostly highly generalist fish, which add many new links to the web. Tide pools, however, add not only diversity but also complexity. Webs were dominated by intermediate species, with the proportion of top consumers fluctuating throughout the tidal cycle, being lowest during low tide and highest at high tide, due to the incoming larger vertebrate predators. Consumer taxa outnumbered resource taxa, except at low tide when pools are present. Mean trophic level was lowest at low tide (2.3) and highest at high tide with pools (2.6). Omnivory was high and showed little change. “Chain”, the number of links connecting top to basal species, was stable but low. This implies that disturbance can rapidly travel bottom-up or top-down through predator-prey links. The increased connectance given by the addition of tide pools likely increases robustness to disturbances, an important feature in coastal areas so often impacted by human action.

Innovation through anachronism: The Pony Express, media, and American modernities

Historically, the relationship between innovation and technology has formed an important element of Euro-American identity. However, such a view ignores older or alternative media forms and practices, contributing to a conception of modernity as future-oriented, obscuring the importance of transitional moments during which the value and meaning of new media develop and new senses of community identity can be defined. As we live through a transitional moment with new forms of technological media emerging in shortening cycles of time and with American identity in conflict and flux, re-assessing the relationship between innovation, technological media, and modernity is urgent. The mid-19th century likewise was a time of social, technological, and cultural change. Following a media archeological method, I focus on a messaging system from the 19th century, the Pony Express, which was in operation for only 18 months, but became a media phenomenon whose imaginative influence lasted into the 21st century. The Pony Express’s success as a messenger demonstrates how an anachronistic communications system solved a problem of American modernization – the need for networked connection across long distances – and shows how such a system provided imaginative and iconographic frameworks for maintaining a sense of American identity at a time of change.