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Ecology and Evolutionary Biology

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Evaluation And Demographic Response Of The Shovelnose Sturgeon Commercial Caviar Fishery In The Wabash River, Jessica L. Thornton Jan 2018

Evaluation And Demographic Response Of The Shovelnose Sturgeon Commercial Caviar Fishery In The Wabash River, Jessica L. Thornton

Masters Theses

Shovelnose sturgeon (Scaphirhynchus platorynchus Rafinesque) are considered one of the last commercially viable options for sturgeon roe harvest. Due to the collapse of several marine sturgeon fisheries and the Similarity of Appearances provision which protect shovelnose sturgeon in only a part of their range, the caviar fishery in the Wabash River remains an important point of supply for this lucrative natural resource. In this thesis, I presented an evaluation of the shovelnose sturgeon commercial caviar fishery in the Wabash River. More specifically, I described the demographic response of this population to continued exploitation over a 10-year period. Additionally, I …

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Impact Of Temperature Increase On Freshwater Fish Species: Energetics And Muscle Mechanics Of Two Centrarchids, Israt Jahan Jan 2018

Impact Of Temperature Increase On Freshwater Fish Species: Energetics And Muscle Mechanics Of Two Centrarchids, Israt Jahan

Masters Theses

Fishes have evolved physiologically to live within a specific range of environmental variation and existence outside of that range can be stressful or fatal. These ranges can coincide for fishes that evolved in similar habitats. This study investigates physiological processes limiting thermal tolerance, specifically how changes in water temperature affect the swimming energetics and muscle mechanics in largemouth bass (Micropterus salmoides) and bluegill (Lepomis macrochirus). I focused on the impact of temperature change at the muscle level in these two species and the capacity to adapt to rapid changes in the environment. Fish were housed at …

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Avian Community Responses To Bison Grazing In North American Intermountain Grasslands, Danielle A. Fagre Jan 2018

Avian Community Responses To Bison Grazing In North American Intermountain Grasslands, Danielle A. Fagre

Graduate Student Theses, Dissertations, & Professional Papers

Grassland and shrubland songbird species are a guild of conservation concern in North America. Many of these species have experienced severe population declines, due to habitat loss and land use change. This makes the conservation and management of remaining habitat of crucial importance for this guild. Grazing by large herbivores is an ecosystem process in grassland systems, and in North America, one of the major historic grazers was the Plains bison (Bison bison). Bison are considered ecosystem engineers, because they modify habitat to be more or less suitable for other species, such as grassland and shrubland songbirds. Bison …

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The Ethosophy Of The Grizzly Man: Timothy Treadwell's Three Ethologies, Blake L. Ginsburg Jan 2018

The Ethosophy Of The Grizzly Man: Timothy Treadwell's Three Ethologies, Blake L. Ginsburg

Graduate Student Theses, Dissertations, & Professional Papers

This paper explores the ethical appropriateness and significance of Timothy Treadwell’s life among the bears and foxes of Alaska’s Katmai National Park and Preserve. In an attempt to reveal the formative and transformative aspects of Treadwell’s project, I rely upon an ethological framework developed by Matthew Calarco that moves beyond the narrow conception of ethology as a scientific practice aimed at systematic and rigorous documentation of the quantifiable aspects of animal behavior. While many people might be hesitant to conceive of Treadwell’s project as an ethological one, I hope to illuminate the ways in which his life among bears and …

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Arthropod Diets In Chihuahuan Desert Snakes, Victor Manuel Parga Jan 2018

Arthropod Diets In Chihuahuan Desert Snakes, Victor Manuel Parga

Open Access Theses & Dissertations

Over the past century, studies in herpetology regarding snake diets have been commonly focused on those species that feed or specialize in vertebrate prey items. For those that feed primarily on invertebrates however, little work has been done in determining diet specializations and comparing diets within a community of species. This Thesis focuses on small species of snakes that feed primarily on arthropods in a Chihuahuan Desert community, and will investigate if these are diet generalists or specialists. To this end, stomach contents were examined from preserved specimens of the following species: Rena humilis and Rena dissecta (Leptotyphlopidae), Gyalopion canum …

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Estimating Exploitation Rates In The Alabama Red Snapper Fishery Using A High-Reward Tag–Recapture Approach, Dana K. Sackett, Mattgew Catalano, J. Marcus Drymon, Sean P. Powers, Mark Albins Jan 2018

Estimating Exploitation Rates In The Alabama Red Snapper Fishery Using A High-Reward Tag–Recapture Approach, Dana K. Sackett, Mattgew Catalano, J. Marcus Drymon, Sean P. Powers, Mark Albins

University Faculty and Staff Publications

Accurate estimates of exploitation are essential to managing an exploited fishery. However, these estimates are often dependent on the area and vulnerable sizes of fish considered in a study. High-reward tagging studies offer a simple and direct approach to estimating exploitation rates at these various scales and in examining how model parameters impact exploitation rate estimates. These methods can ultimately provide a better understanding of the spatial dynamics of exploitation at smaller local and regional scales within a fishery—a measure often needed for more site-attached species, such as the Red Snapper Lutjanus campechanus. We used this approach to tag 724 …

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Comparative Phylogeography, Taxonomy, And Neuroanatomy Of Montane Chameleons In The Albertine Rift, Central Africa, Daniel Hughes Jan 2018

Comparative Phylogeography, Taxonomy, And Neuroanatomy Of Montane Chameleons In The Albertine Rift, Central Africa, Daniel Hughes

Open Access Theses & Dissertations

How do traits vary across the tree of life? Our ability to address this question is diminished if: A taxonomic group has a poorly sampled phylogeny, a species goes extinct before their systematic position is resolved, or a trait is inadequately characterized for detailed studies. In the current era of mass extinction, it is imperative to not only accelerate species discovery through traditional studies in taxonomy and expeditionary research, but also to increase rescue efforts for all types of data before poorly understood species and potentially undescribed traits are lost. Here, an integrative taxonomic approach was used and novel methods …

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Hidden Diversity In Aquatic Habitats: Lessons From Cryptic Species In Microscopic Invertebrates (Rotifera), Azar Kordbacheh Jan 2018

Hidden Diversity In Aquatic Habitats: Lessons From Cryptic Species In Microscopic Invertebrates (Rotifera), Azar Kordbacheh

Open Access Theses & Dissertations

Speciation is a continuous and adaptive process by which lineages are diverged into multiple groups, and species are the product of this process. Taxonomy is the study of relationship between organisms, classifying and naming them, and one of the taxonomical challenges is delimiting species boundaries. Species delimitation can be controversial because biologists do not agree on species concepts and approaches for defining species boundaries. One of the well-known species concepts is the Biological Species Concept that requires studying reproductive barriers among populations. Investigating strength of reproductive isolation among populations is not always practical in the wild. Therefore, many biologists have …

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Omnivore Density Affects Community Structure Through Multiple Trophic Cascades, Donald J. Benkendorf Jan 2018

Omnivore Density Affects Community Structure Through Multiple Trophic Cascades, Donald J. Benkendorf

Murray State Theses and Dissertations

Omnivores can dampen trophic cascades by feeding at multiple trophic levels, yet few studies have evaluated how intraspecific variation influences the effect of omnivores on community structure. The Speckled Dace (Rhinichthys osculus) is an omnivorous cyprinid that consumes algae and invertebrates and is abundant throughout the western United States. I sought to identify the effects of size and size structure on top-down control by dace and learn how these effects scaled with density. Dace were manipulated in a mesocosm experiment and resulting changes in invertebrate and algal communities and measures of ecosystem function were monitored. Omnivores affected experimental …

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Spatial Modelling And Wildlife Health Surveillance: A Case Study Of White Nose Syndrome In Ontario, Lauren Yee Jan 2018

Spatial Modelling And Wildlife Health Surveillance: A Case Study Of White Nose Syndrome In Ontario, Lauren Yee

Theses and Dissertations (Comprehensive)

Wildlife data is often limited by survey effort, small sample sizes, and spatial biases associated with collection and missing data. These factors can create unique challenges from a surveillance perspective when trying to extract spatial patterns of habitat suitability and disease distributions for conservation and management purposes. This thesis examined data quality from a wildlife health database in the context of spatial analysis of wildlife disease. Spatial analysis of the data to predict habitat suitability of bats and white nose syndrome afflicted bats was examined by using the MaxEnt modelling method. Methods to reduce spatial bias were examined and specific …

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Predictors Of Fish Assemblage Structure And Dynamics In Atlantic Coastal Plain Streams, Rebecca Scott Jan 2018

Predictors Of Fish Assemblage Structure And Dynamics In Atlantic Coastal Plain Streams, Rebecca Scott

College of Graduate Studies: Theses & Dissertations

Effective management of freshwater fishes requires a mechanistic understanding of the drivers of assemblage composition; in other words, what determines who is where and when. Stream fish assemblages are potentially influenced by environmental factors that act on multiple spatiotemporal scales, but the relative influence of these drivers may vary between geophysically distinct regions. This study sought to determine the patterns and drivers of fish taxonomic and functional assemblage composition in the coastal plain, a region possessing unique hydrologies, faunas, and physiochemical conditions. I addressed this goal using two complementary chapters, both of which utilized environmental and biotic data collected from …

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Comparison Of Three Benthic Macroinvertebrate Passive Sampling Devices For Non-Wadeable Streams, Kelsey A. Laymon Jan 2018

Comparison Of Three Benthic Macroinvertebrate Passive Sampling Devices For Non-Wadeable Streams, Kelsey A. Laymon

College of Graduate Studies: Theses & Dissertations

Rivers and streams provide essential ecosystem services to the degree that the monitoring and maintenance of these systems becomes imperative. Biomonitoring provides managers and policymakers with the tools to make informed decisions, and macroinvertebrates are often the object of biomonitoring because they are ubiquitous in most systems and are known to be good indicators of water quality. However, methods for sampling macroinvertebrates in non-wadeable streams (i.e., large rivers) have not been standardized across states and regions and an established method for macroinvertebrate biomonitoring in large rivers of Georgia is not currently available. My study compared macroinvertebrates collected with three types …

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Characterizing The Complex Relationship Between The Brown Widow Spider And Its Bacterial Endosymbiont, Wolbachia, Emily Knight Jan 2018

Characterizing The Complex Relationship Between The Brown Widow Spider And Its Bacterial Endosymbiont, Wolbachia, Emily Knight

College of Graduate Studies: Theses & Dissertations

The brown widow spider, Latrodectus geometricus (C. L. Koch 1841), has been found to harbor the maternally inherited bacterial endosymbiont Wolbachia pipientis (Hertig and Wolbach 1924), but endosymbiont infection frequency varies widely among Southeastern US populations. Wolbachia is known to manipulate the reproduction of its hosts through male feminization, parthenogenesis, male killing, and cytoplasmic incompatibility. In brown widows, Wolbachia does not alter sex ratios, but any other effects the symbiont has on the spider are unknown. In my first chapter, I assess if there is linkage between Wolbachia infection and maternally inherited mitochondrial DNA (mtDNA) in three brown widow populations. …

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Foraging Ecology Of A Winter Bird Community In Southeastern Georgia, Rachel E. Mowbray Jan 2018

Foraging Ecology Of A Winter Bird Community In Southeastern Georgia, Rachel E. Mowbray

College of Graduate Studies: Theses & Dissertations

Classical views on community structure emphasized deterministic processes and the importance of competition in shaping communities. However, the processes responsible for shaping avian communities remain controversial. Attempts to understand distributions and abundances of species are complicated by the fact that birds are highly mobile. Many species migrate biannually between summer breeding grounds and wintering grounds. The goal of this study was to test four hypotheses that attempt to explain how migratory species integrate into resident assemblages of birds (Empty-Niche Hypothesis, Competitive-Exclusion Hypothesis, Niche-Partitioning Hypothesis, and Generalist-Migrant Hypothesis). I collected data on birds foraging during the winter of 2017-2018 in Magnolia …

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Researchers, Not Dogs, Lack Control In An Experiment On Jealousy, Jennifer Vonk Jan 2018

Researchers, Not Dogs, Lack Control In An Experiment On Jealousy, Jennifer Vonk

Animal Sentience

Cook and colleagues (2018) have developed a clever method to measure fMRI in awake dogs in response to a number of interesting stimuli. As a result, they are able to determine neural correlates of observable behavior. They report that dogs may experience something akin to jealousy because they show greater amygdala activation in response to food being given to a fake dog versus food being placed in a bucket. However, several critical controls are missing which prevent the authors from being able to speak of jealousy.

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Finding The Green-Eyed Monster In The Brain Of A Dog, Peter Singer Jan 2018

Finding The Green-Eyed Monster In The Brain Of A Dog, Peter Singer

Animal Sentience

That dogs show behavior suggestive of jealousy has long been known and has been demonstrated under controlled conditions. Cook et al. have now shown arousal in the amygdala when dogs see a caregiver feeding another dog. This finding has ethical significance in two respects. First, the consideration shown by the investigators for the welfare of their experimental subjects sets an example for other researchers using animals. Second, the greater understanding of the emotional lives of animals should lead to more concern for their needs.

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Jealousy, Competition, Or A Contextual Cue For Reward?, Thomas R. Zentall Jan 2018

Jealousy, Competition, Or A Contextual Cue For Reward?, Thomas R. Zentall

Animal Sentience

Emotions are difficult to assess, even in humans. The attribution of jealousy in an animal like a dog is especially difficult because performance of a particular behavior in the context of another animal receiving a reward may not be easily distinguishable from intra-species competition or simply a response to a contextual cue for the availability of reward. The authors provide distinguishing evidence in the form of fMRI data to show that in the presence of a “fake” dog being fed, there is bilateral activation in the amygdala, an area associated with anxiety, anger, fear, and even jealousy in humans.

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What Can The Social Emotions Of Dogs Teach Us About Human Emotions?, Dean Mobbs Jan 2018

What Can The Social Emotions Of Dogs Teach Us About Human Emotions?, Dean Mobbs

Animal Sentience

It has long been believed that social emotions such as guilt and jealousy are only expressed in humans. In the case of jealousy, its adaptive value has been linked to the prevention of sexual infidelity or fairness. So why would dogs feel jealousy? I suggest that understanding how social emotions have been bred into dogs can help us understand our own emotions, including their functionality — and potentially their mechanisms.

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Can Neuroimaging In Dogs Have Practical Implications?, Tiffani J. Howell Jan 2018

Can Neuroimaging In Dogs Have Practical Implications?, Tiffani J. Howell

Animal Sentience

Jealousy, or at least aggression, can be observed in dogs using neuroimaging techniques, but this response attenuates quickly following repeated exposure to the aggression-inducing stimulus. This may have a practical application. Early socialisation as a puppy, and habituation as an adult dog, could help prevent undesirable behaviours such as predatory behaviour. It is unclear whether these processes are the same, and affected only by the dog’s age. Neuroimaging could help us understand whether the same neurological processes underlie socialisation and habituation, and whether self-rewarding behaviours such as predatory behaviour could be stopped using socialisation/habituation techniques.

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Lessons From Behaviour For Brain Imaging, Carolyn J. Walsh Jan 2018

Lessons From Behaviour For Brain Imaging, Carolyn J. Walsh

Animal Sentience

Integrating physiological and behavioural arousal with social context is fundamental to understanding affect in dogs. Cook et al. (2018) have made a worthy start towards illuminating the neural basis of dog affect underlying resource loss. However, their study depends on retrospective behaviour reports versus direct testing, and an interpretation of differential neural activation that is based on too few dogs. Research groups conducting canine brain-imaging work might: (1) consider collaborative approaches to augment sample sizes and replicability, and (2) take a recent lesson from dog behavioural research regarding a more cautious approach to applying functional labels to physiological and/or behavioural …

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On Jealousy, Envy, Sex Differences And Temperament In Humans And Dogs, Eddie Harmon-Jones, Sylvia K. Harmon-Jones Jan 2018

On Jealousy, Envy, Sex Differences And Temperament In Humans And Dogs, Eddie Harmon-Jones, Sylvia K. Harmon-Jones

Animal Sentience

Cook, Prichard, Spivak, and Berns (2018) find that dogs’ levels of trait aggression are positively correlated with their amygdala activation when observing their caregivers giving a food to a fake dog. The authors conclude that this may provide neural evidence in dogs for the experience of jealousy, an emotion that some psychologists consider to be unique to humans. Here we explain the difference between the emotions of jealousy and envy, suggesting some ideas for future experiments that may help disentangle the experience of jealousy from that of envy in dogs. We also propose ideas for future research that may yield …

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Inferring Emotion From Amygdala Activation Alone Is Problematic, Thomas F. Denson Jan 2018

Inferring Emotion From Amygdala Activation Alone Is Problematic, Thomas F. Denson

Animal Sentience

Cook et al. investigated neural responses in domestic dogs in an experiment designed to elicit jealousy. Relative to a control condition, watching the dogs’ caregivers feed a fake dog activated the amygdala bilaterally. Dogs rated higher in dog-directed aggressiveness showed larger initial amygdala activation. Amygdala activity in this context is insufficient evidence to infer that the dogs experienced jealousy or even negative affect. The experimental design does not provide an adequate level of control to infer the presence of jealousy.

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Jealousy? Or Just Hostility Toward Other Dogs? The Risks Of Jumping To Conclusions, James A. Serpell Jan 2018

Jealousy? Or Just Hostility Toward Other Dogs? The Risks Of Jumping To Conclusions, James A. Serpell

Animal Sentience

Cook et al. (2018) provide a fascinating demonstration of amygdala activation in dogs when they witnessed their owners giving food to another (fake) dog, but not when they placed food in a bucket. Dogs’ neurological responses were positively correlated with their reported levels of ‘dog-directed aggression’ as measured by the C-BARQ, and dogs with initially strong amygdala responses habituated on subsequent trials. The authors interpret their findings as possible evidence for an emotion akin to jealousy in dogs. However, alternate interpretations involving either dog aggression/fear or emotional responses to food seem more plausible and avoid the welfare risks associated with …

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What Would We Like To Know By Imaging The Brains Of Dogs?, Ralph Adolphs Jan 2018

What Would We Like To Know By Imaging The Brains Of Dogs?, Ralph Adolphs

Animal Sentience

Using fMRI to study emotions in animals is important, fascinating, and fraught with methodological and conceptual problems. Cook et al. are doing it, and there is no question that they and others will be doing it better and better as time goes on. Where will this lead us? What could fMRI in principle tell us about the minds of nonhuman animals?

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Dogs Aren’T Jealous – They Are Just Asking For Accurate Information, Karen L. Overall Jan 2018

Dogs Aren’T Jealous – They Are Just Asking For Accurate Information, Karen L. Overall

Animal Sentience

Awake fMRI offers us a unique opportunity to view and understand how dogs see the world and use the information in it. Given the limitations of behavioral assays and the small sample sizes inherent in these studies, labeling of patterns of canine behaviors using pop psychology terms may actually interfere with our understanding of canine brains and obscure for us a more parsimonious but exciting interpretation of canine behavior. We should use this window into how dogs think wisely.


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Situating The Study Of Jealousy In The Context Of Social Relationships, Christine E. Webb, Frans B. M. De Waal Jan 2018

Situating The Study Of Jealousy In The Context Of Social Relationships, Christine E. Webb, Frans B. M. De Waal

Animal Sentience

Whereas the feelings of other beings are private and may always remain so, emotions are simultaneously manifested in behavior, physiology, and other observables. Nonetheless, uncertainty about whether emotions can be studied adequately across species has promoted skepticism about their very presence in other parts of the animal kingdom. Studying social emotions like jealousy in the context of the social relationships in which they arise, as has been done in the case of animal empathy, may help dispel this skepticism. Empathy in other species came to be accepted partly because of the behavioral similarities between its expression in nonhuman animals and …

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Sentient Plants? Nervous Minds?, Arthur S. Reber Jan 2018

Sentient Plants? Nervous Minds?, Arthur S. Reber

Animal Sentience

The commentaries by Calvo (2018) and Mallatt & Feinberg (2017) on my 2016 target branch out from a common conceptual node like forks in a road. Calvo criticizes me for not acknowledging that plants too are likely to be sentient and claims I have fallen into the kind of category error of which I accuse others ─ a zoocentric bias that fails to grant consciousness to flora. Mallatt & Feinberg maintain that I've gone too far in granting sentience to any species that lacks a nervous system. Calvo makes some good points but there are other issues concerning plant sentience …

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Individuals In The Wild, Bob Fischer Jan 2018

Individuals In The Wild, Bob Fischer

Animal Sentience

If many wild animals have net negative lives, then we have to consider how likely it is that the good for animals, considered as individuals, aligns with the good for species, or the climate, or the preservation of wild spaces.

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How To Foster Respect For Animals? Superiority, Dissimilarity, And Prejudice, Matteo Colombo Jan 2018

How To Foster Respect For Animals? Superiority, Dissimilarity, And Prejudice, Matteo Colombo

Animal Sentience

Chapman & Huffman (C & H) might be taken to argue as follows: Humans may treat animals however they want only if humans are superior to animals. But humans are not superior to animals. Therefore, humans may not treat animals however they want. Whatever its merit, this is not C & H’s actual argument. Their point, instead, is that humans often mistreat animals because they tend to perceive them as inferior. A remedy for animal mistreatment would then be acknowledging the deep similarities between us and animals. But is C & H’s suggested remedy likely to be effective to foster …

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Insulting Words: "They Are Animals!", Carolyn A. Ristau Jan 2018

Insulting Words: "They Are Animals!", Carolyn A. Ristau

Animal Sentience

As Chapman & Huffman state, creating divisive human categories has rationalized atrocities committed against the “other.” Labeling neighboring warring villagers as “animals” is considered a despicable insult. Yet contemporary scientific views of many animals grant them thinking and conscious faculties, and the capacity for impressive achievements, many unattainable by humans. Robots, too, can accomplish many similar feats. But the essential reason we must protect animals is not because of their admirable abilities, but their capacity for consciousness, for suffering. Robots are not conscious. Participants in the human-animal debate should not complain about changing criteria for determining human uniqueness. New and …

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