Jacob Dunn

Jacob Dunn
Anglia Ruskin University | ARU · Department of Life Sciences

PhD

About

67
Publications
28,146
Reads
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951
Citations
Citations since 2016
46 Research Items
743 Citations
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2016201720182019202020212022050100150
Introduction
My research interests are in the general area of evolutionary ecology, encompassing and integrating the fields of bioacoustics, morphology, behavioural ecology, molecular ecology and eco-physiology.
Additional affiliations
July 2016 - present
Anglia Ruskin University
Position
  • Professor (Associate)
January 2010 - July 2016
University of Cambridge
Position
  • Lecturer
October 2006 - December 2009
University of Barcelona
Position
  • PhD Student

Publications

Publications (67)
Article
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Males often face a trade-off between investments in precopulatory and postcopulatory traits [1], particularly when male-male contest competition determines access to mates [2]. To date, studies of precopulatory strategies have largely focused on visual ornaments (e.g., coloration) or weapon morphology (e.g., antlers, horns, and canines). However, v...
Article
Acoustic allometry consists of looking at how an organism’s body size scales with the characteristics of its vocalizations. A typical finding based on this framework is that across mammals body size is reflected in the fundamental frequency (fo) of vocalizations, whereby lower fo indicates larger body size [1]. This relationship holds owing to the...
Article
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Tissue vibrations in the larynx produce most sounds that comprise vocal communication in mammals. Larynx morphology is thus predicted to be a key target for selection, particularly in species with highly developed vocal communication systems. Here, we present a novel database of digitally modeled scanned larynges from 55 different mammalian species...
Article
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Relative brain size has long been considered a reflection of cognitive capacities and has played a fundamental role in developing core theories in the life sciences. Yet, the notion that relative brain size validly represents selection on brain size relies on the untested assumptions that brain-body allometry is restrained to a stable scaling relat...
Article
Human speech production obeys the same acoustic principles as vocal production in other animals but has distinctive features: A stable vocal source is filtered by rapidly changing formant frequencies. To understand speech evolution, we examined a wide range of primates, combining observations of phonation with mathematical modeling. We found that s...
Article
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The drivers of divergent scleral morphologies in primates are currently unclear, though white sclerae are often assumed to underlie human hyper-cooperative behaviours. Humans are unusual in possessing depigmented sclerae whereas many other extant primates, including the closely-related chimpanzee, possess dark scleral pigment. Here, we use phylogen...
Article
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The transformation and depletion of primary forest over the past few decades have placed almost half of the world's primate species under the threat of extinction. Developing any successful conservation program for primates requires distribution and demography data, as well as an understanding of the relationships between these factors and their ha...
Article
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The study of animal play is highly complex since its potential functions vary with social and environmental circumstances. Although play is generally characteristic of immature animals, it may persist in adults in its social form, particularly when interacting with young individuals, and less often with other adult playmates. We measured the amount...
Article
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Mehr et al.'s hypothesis that the origins of music lie in credible signaling emerges here as a strong contender to explain early adaptive functions of music. Its integration with evolutionary biology and its specificity mark important contributions. However, much of the paper is dedicated to the exclusion of popular alternative hypotheses, which we...
Preprint
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Primate gaze following behaviors are of great interest to evolutionary scientists studying social cognition. The ability of an organism to determine a conspecifics likely intentions from their gaze direction may confer an advantage to individuals in a social group. This advantage could be cooperative and/or competitive. Humans are unusual in posses...
Article
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Character displacement, or a shift in traits where species co-occur, is one of the most common ecological patterns to result from interactions between closely related species. Usually, character displacement is associated to divergence in traits, though, they might be convergent, especially when used for aggressive interference between species. In...
Article
Relative brain size has long been considered a reflection of cognitive capacities and has played a fundamental role in developing core theories in the life sciences. Yet, the notion that relative brain size validly represents selection on brain size relies on the untested assumptions that brain-body allometry is restrained to a stable scaling relat...
Article
Full-text available
A common recommendation in the field of animal chemosignaling is to store and transport scent samples frozen, since they are likely to change with time and degrade due to bacterial activity inside the sample containers and the loss of the most volatile compounds. However, we still ignore the exact pattern of change or degradation for these types of...
Article
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Olfactory communication is an important mediator of social interactions in mammals, thought to provide information about an individual’s identity and current social, reproductive, and health status. In comparison with other taxa such as carnivores and rodents, few studies have examined primate olfactory communication. Tamarins (Callitrichidae) cons...
Article
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Chemosignals are mediators of social interactions in mammals, providing con‐ and hetero‐specifics with information on fixed (e.g., species, sex, group, and individual identity) and variable (e.g., social, reproductive, and health status) features of the signaler. Yet, methodological difficulties of recording and quantifying odor signals, especially...
Preprint
Chemosignals are mediators of social interactions in mammals, providing con- and hetero-specifics with information on fixed (e.g. species, sex, group and individual identity) and variable (e.g. social, reproductive and health status) features of the signaler. Yet methodological difficulties of recording and quantifying odor signals, especially in f...
Article
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Fragmented tropical forests can be highly dynamic, with the spatial configuration of forest patches changing through time. Yet, the lack of longitudinal studies limits our understanding of how patch dynamics affect biodiversity, especially when there is a time lag in species extinctions (extinction debt). We assessed how temporal changes in patch s...
Article
Genetic diversity provides populations with the possibility to persist in ever‐changing environments, where selective regimes change over time. Therefore, the long‐term survival of a population may be affected by its level of genetic diversity. The Mexican howler monkey (Alouatta palliata mexicana ) is a critically endangered primate restricted to...
Article
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The evolutionary origins of how modern humans share and use space are often modelled on the territorial-based violence of chimpanzees, with limited comparison to other apes. Gorillas are widely assumed to be non-territorial due to their large home ranges, extensive range overlap, and limited inter-group aggression. Using large-scale camera trapping...
Preprint
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Segmentation of high-resolution tomographic data is often an extremely time-consuming task and until recently, has usually relied upon researchers manually selecting materials of interest slice by slice. With the exponential rise in datasets being acquired, this is clearly not a sustainable workflow. In this paper, we apply the Trainable Weka Segme...
Article
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Understanding the nature of the relationship between vocal complexity and brain architecture across non-human primates may help elucidate some of the key elements underlying the evolution of human speech. Here, we report a positive correlation between vocal repertoire size and the relative size of cortical association areas (governing voluntary con...
Article
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Fundamental frequency (fo) is often estimated based on electroglottographic (EGG) signals. Because of the nature of the method, the quality of EGG signals may be impaired by certain features like amplitude or baseline drifts, mains hum, or noise. The potential adverse effects of these factors on fo estimation have to date not been investigated. Her...
Article
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One noteworthy, but unexplained aspect of the evolution of human speech is the loss of laryngeal air sacs during hominin evolution. Very little is known about the adaptive significance of this curious trait, or the selection pressures that may have driven their evolution among primates, and later loss in Homo. Here, I review the literature on the l...
Article
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Electroglottography (EGG) is a low-cost, non-invasive method for documenting laryngeal sound production during vocalization. The EGG signal represents relative vocal fold contact area and thus delivers physiological evidence of vocal fold vibration. While the method has received much attention in human voice research over the last five decades, it...
Article
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A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has been fixed in the paper.
Article
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Range defensibility is defined as the ability of animals to efficiently move over an area to monitor and defend it. Therefore, range defensibility can help us understand the spatial structure of animal territoriality. We used howler monkeys (Alouatta spp.), a genus for which no agreement on the extent of their territoriality exists, to investigate...
Article
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A correction to this article has been published and is linked from the HTML version of this paper. The error has not been fixed in the paper.
Article
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A fundamental issue in the evolution of communication is the degree to which signals convey accurate (" honest ") information about the signaler. In bioacoustics, the assumption that fundamental frequency (fo) should correlate with the body size of the caller is widespread, but this belief has been challenged by various studies, possibly because la...
Article
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Long-term field studies are critical for our understanding of animal life history and the processes driving changes in demography. Here, we present long-term demographic data for the northernmost population of mantled howler monkeys (Alouatta palliata) residing in a highly anthropogenically fragmented landscape in Los Tuxtlas, Mexico. We carried ou...
Article
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Primates are some of the most playful animals in the natural world, yet the reason for this remains unclear. One hypothesis posits that primates are so playful because playful activity functions to help develop the sophisticated cognitive and behavioural abilities that they are also renowned for. If this hypothesis were true, then play might be exp...
Article
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A fundamental assumption in bioacoustics is that large animals tend to produce vocalizations with lower frequencies than small animals. This inverse relationship between body size and vocalization frequencies is widely considered to be foundational in animal communication, with prominent theories arguing that it played a critical role in the evolut...
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Natural selection has resulted in the acoustic convergence of many animal vocalizations. During agonistic interactions vocalizations may vary depending on the role an individual plays in the interaction and on the severity of the attack. Motivation-structural rules describe how aggressors are thought to have evolved to use low-frequency vocalizatio...
Article
Full-text available
Long-term field studies of primates are critical for our understanding of life history and the processes driving changes in demography. Here, we present the first long-term demographic data for the northernmost population of the mantled howler monkey (Alouatta palliata). We followed 10 groups of howler monkeys living in a highly fragmented landscap...
Chapter
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Lianas are becoming an increasingly prominent component of tropical forests. This chapter evaluates the use of lianas by primates an abundant, species-rich, and ecologically important order of mammals. The great majority of primate species are highly arboreal, and they depend on the different strata above the forest floor for feeding, traveling, re...
Article
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There are a growing number of reports of antibiotic resistance (ATBR) in bacteria living in wildlife. This is a cause for concern as ATBR in wildlife represents a potential public health threat. However, little is known about the factors that might determine the presence, abundance and dispersion of ATBR bacteria in wildlife. Here, we used culture...
Article
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The Mexican howler monkey (Alouatta palliata mexicana) is a critically endangered primate, which is paleoendemic to Mexico. However, despite the potential significance of genetic data for its management and conservation, there have been no population genetic studies of this subspecies. To examine genetic diversity in the key remaining forest refuge...
Article
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Environmental stressors impact physiology in many animal species. Accordingly, the monitoring of fecal glucocorticoid metabolites (fGCM) has been increasingly used to evaluate the physiological costs of habitat disturbance on wild animal populations, providing a powerful tool for conservation and management. Several studies have suggested that prim...
Chapter
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In 2010, the Food and Agriculture Organization of the United Nations (FAO) estimated that 16 million hectares of forest per year were lost globally in the 1990s (FAO 2010), and approximately 12.5 million hectares/year were lost in countries with primate populations, an area just smaller than Greece or the US State of Mississippi (Chapman and Peres...
Chapter
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The region of Los Tuxtlas in the state of Veracruz, southeast Mexico, represents the northernmost limit of tropical rainforest in the Americas and is home to populations of two primate species, the Mexican howler monkey ( Alouatta palliata mexicana ) and the Mexican spider monkey ( Ateles geoffroyi vellerosus ). Los Tuxtlas, like many other regions...
Article
Lianas are important components in the dynamics of tropical forests and represent fallback foods for some primates, yet little is known about their impact on primate ecology, behavior or fitness. Using 2 yr of field data, we investigated liana consumption and foraging effort in four groups of howler monkeys (two in bigger, more conserved forest fra...
Article
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Little is known about how resource limitation affects the feeding ecology of primates in forest fragments. Here, we describe seasonal variation in the diet and feeding effort of 2 groups (RH and RC3) of howlers (Alouatta palliata mexicana) living in different sized forest fragments in Los Tuxtlas, Mexico. The RH group, which lived in a larger and m...
Article
Many animal populations are forced to inhabit very small forest patches, which may threaten their long-term survival. In some cases, animals in these forest remnants are able to supplement their diet by using resources outside of their home patch, a process named ‘landscape supplementation’. Although this is probably a key process for population su...