scholarly journals Differences in adrenocortical responses between urban and rural burrowing owls: poorly-known underlying mechanisms and their implications for conservation

2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Antonio Palma ◽  
Julio Blas ◽  
José L Tella ◽  
Sonia Cabezas ◽  
Tracy A Marchant ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Urban Areas ◽  
Habitat Choice ◽  
Stressful Events ◽  
External Information ◽  
Athene Cunicularia ◽  
Conservation Implications ◽  
Underlying Mechanisms ◽  
Lower Magnitude ◽  
Adrenocortical Responses

Abstract The hypothalamus–pituitary–adrenal/interrenal (HPA) axis of vertebrates integrates external information and orchestrates responses to cope with energy-demanding and stressful events through changes in circulating glucocorticoid levels. Urbanization exposes animals to a wide variety of ever-changing stimuli caused by human activities that may affect local wildlife populations. Here, we empirically tested the hypothesis that urban and rural owls (Athene cunicularia) show different adrenocortical responses to stress, with urban individuals showing a reduced HPA-axis response compared to rural counterparts to cope with the high levels of human disturbance typical of urban areas. We applied a standard capture-restraint protocol to measure baseline levels and stress-induced corticosterone (CORT) responses. Urban and rural owls showed similar circulating baseline CORT levels. However, maximum CORT levels were attained earlier and were of lower magnitude in urban compared to rural owls, which showed a more pronounced and long-lasting response. Variability in CORT responses was also greater in rural owls and contained the narrower variability displayed by urban ones. These results suggest that only individuals expressing low-HPA-axis responses can thrive in cities, a pattern potentially mediated by three alternative and non-exclusive hypotheses: phenotypic plasticity, natural selection and matching habitat choice. Due to their different conservation implications, we recommend further research to properly understand wildlife responses to humans in an increasingly urbanized world.

scholarly journals GPER-Deficient Rats Exhibit Lower Serum Corticosterone Level and Increased Anxiety-Like Behavior

2020 ◽  
Vol 2020 ◽  
pp. 1-22 ◽  
Author(s):  
Yi Zheng ◽  
Meimei Wu ◽  
Ting Gao ◽  
Li Meng ◽  
Xiaowei Ding ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Corticosterone Level ◽  
Brain Structures ◽  
Ample Evidence ◽  
Genetic Ablation ◽  
Serum Corticosterone ◽  
Underlying Mechanisms ◽  
G Protein Coupled ◽  
Prolonged Stress

Ample evidence suggests that estrogens have strong influences on the occurrence of stress-related mood disorders, but the underlying mechanisms remain poorly understood. Through multiple approaches, we demonstrate that the G protein-coupled estrogen receptor (GPER) is widely distributed along the HPA axis and in brain structures critically involved in mood control. Genetic ablation of GPER in the rat resulted in significantly lower basal serum corticosterone level but enhanced ACTH release in response to acute restraint stress, especially in the female. GPER-/- rats of either sex displayed increased anxiety-like behaviors and deficits in learning and memory. Additionally, GPER deficiency led to aggravation of anxiety-like behaviors following single-prolonged stress (SPS). SPS caused significant decreases in serum corticosterone in WT but not in GPER-deficient rats. The results highlight an important role of GPER at multiple sites in regulation of the HPA axis and mood.

scholarly journals Evolution of genomic variation in the burrowing owl in response to recent colonization of urban areas

2018 ◽  
Vol 285 (1878) ◽  
pp. 20180206 ◽  
Author(s):  
Jakob C. Mueller ◽  
Heiner Kuhl ◽  
Stefan Boerno ◽  
Jose L. Tella ◽  
Martina Carrete ◽  
...  
Keyword(s):  
Urban Areas ◽  
Demographic History ◽  
Genomic Variation ◽  
Rural Populations ◽  
Urban Habitat ◽  
Restricted Gene Flow ◽  
Athene Cunicularia ◽  
Urban Populations ◽  
Burrowing Owl ◽  
Standing Variation

When a species successfully colonizes an urban habitat it can be expected that its population rapidly adapts to the new environment but also experiences demographic perturbations. It is, therefore, essential to gain an understanding of the population structure and the demographic history of the urban and neighbouring rural populations before studying adaptation at the genome level. Here, we investigate populations of the burrowing owl ( Athene cunicularia ), a species that colonized South American cities just a few decades ago. We assembled a high-quality genome of the burrowing owl and re-sequenced 137 owls from three urban–rural population pairs at 17-fold median sequencing coverage per individual. Our data indicate that each city was independently colonized by a limited number of founders and that restricted gene flow occurred between neighbouring urban and rural populations, but not between urban populations of different cities. Using long-range linkage disequilibrium statistics in an approximate Bayesian computation approach, we estimated consistently lower population sizes in the recent past for the urban populations in comparison to the rural ones. The current urban populations all show reduced standing variation in rare single nucleotide polymorphisms (SNPs), but with different subsets of rare SNPs in different cities. This lowers the potential for local adaptation based on rare variants and makes it harder to detect consistent signals of selection in the genome.

Examining calorie undernourishment in India: Is it due to choice or inadequacy?

2020 ◽  
pp. 026010602094973
Author(s):  
Udaya S Mishra ◽  
Balakrushna Padhi ◽  
Rinju
Keyword(s):  
Rural Areas ◽  
Urban Areas ◽  
Urban Poor ◽  
Food Choices ◽  
National Sample ◽  
Sample Survey ◽  
The Poor ◽  
Food Expenditure ◽  
Lower Magnitude ◽  
Common Understanding

Background: Calorie undernourishment is often associated with poverty but India presents a unique scene of decline in money-metric poverty and rise in calorie deprivation. Existing literature has varied explanation towards this effect. However, neither are the poor entirely calorie compromised nor do all the non-poor qualify calorie compliance. Aim: This is an attempt at verifying whether calorie undernourishment is a result of choice of food basket or the inadequacy of food expenditure. Method: An answer to this question is attempted with the exploration of data obtained from the National Sample Survey Organization’s Consumption Expenditure of Indian households for the periods 2004–2005 and 2011–2012. Results: Findings reveal that over the last one decade, the average per capita per day calorie intakes have slightly increased from 2040.55 Kcal in 2004–2005 to 2087.33 Kcal in 2011–2012, which has led to the increased share of well-nourished households from 20.21% in the 61st round to 22.78% in the 68th round of survey in rural areas, whereas the similar increase in urban areas is from 36.1% to 40.65%. Conclusions: Calorie undernourishment among the non-poor is observed that calorie undernourishment, if any, among the non-poor is entirely due to choice but the same among the poor has a divide between choice and inadequacy. The urban poor are calorie compromised more due to choice rather than inadequacy as against their rural counterparts. With higher poverty, calorie, non-compliance among the poor is more due to choice when compared with lower magnitude of poverty. These observations form a basis for contesting the common understanding that calorie compromise is entirely driven by inadequacy/incapacity of food expenditure. could be viewed in terms of the food choices made, especially among the poor while setting the minimum threshold of food expenditure to be calorie compliant.

scholarly journals The local hypothalamic–pituitary–adrenal axis in cultured human dermal papilla cells

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Eun Young Lee ◽  
You Jin Nam ◽  
Sangjin Kang ◽  
Eun Ju Choi ◽  
Inbo Han ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Hair Loss ◽  
Human Hair ◽  
Stress Hormones ◽  
Dermal Papilla ◽  
Hair Shaft ◽  
Hair Follicles ◽  
Follicle Cells ◽  
Dermal Papilla Cells ◽  
Underlying Mechanisms

Abstract Background Stress is an important cause of skin disease, including hair loss. The hormonal response to stress is due to the HPA axis, which comprises hormones such as corticotropin releasing factor (CRF), adrenocorticotropic hormone (ACTH), and cortisol. Many reports have shown that CRF, a crucial stress hormone, inhibits hair growth and induces hair loss. However, the underlying mechanisms are still unclear. The aim of this study was to examine the effect of CRF on human dermal papilla cells (DPCs) as well as hair follicles and to investigate whether the HPA axis was established in cultured human DPCs. Results CRF inhibited hair shaft elongation and induced early catagen transition in human hair follicles. Hair follicle cells, both human DPCs and human ORSCs, expressed CRF and its receptors and responded to CRF. CRF inhibited the proliferation of human DPCs through cell cycle arrest at G2/M phase and induced the accumulation of reactive oxygen species (ROS). Anagen-related cytokine levels were downregulated in CRF-treated human DPCs. Interestingly, increases in proopiomelanocortin (POMC), ACTH, and cortisol were induced by CRF in human DPCs, and antagonists for the CRF receptor blocked the effects of this hormone. Conclusion The results of this study showed that stress can cause hair loss by acting through stress hormones. Additionally, these results suggested that a fully functional HPA axis exists in human DPCs and that CRF directly affects human DPCs as well as human hair follicles under stress conditions.

scholarly journals High-intensity urban light installation dramatically alters nocturnal bird migration

2017 ◽  
Vol 114 (42) ◽  
pp. 11175-11180 ◽  
Author(s):  
Benjamin M. Van Doren ◽  
Kyle G. Horton ◽  
Adriaan M. Dokter ◽  
Holger Klinck ◽  
Susan B. Elbin ◽  
...  
Keyword(s):  
New York ◽  
Urban Areas ◽  
Bird Migration ◽  
Light Sources ◽  
Behavioral Alterations ◽  
Conservation Implications ◽  
Nocturnal Bird Migration ◽  
Migrating Birds ◽  
Behavioral Disruptions ◽  
Good Visibility

Billions of nocturnally migrating birds move through increasingly photopolluted skies, relying on cues for navigation and orientation that artificial light at night (ALAN) can impair. However, no studies have quantified avian responses to powerful ground-based light sources in urban areas. We studied effects of ALAN on migrating birds by monitoring the beams of the National September 11 Memorial & Museum's “Tribute in Light” in New York, quantifying behavioral responses with radar and acoustic sensors and modeling disorientation and attraction with simulations. This single light source induced significant behavioral alterations in birds, even in good visibility conditions, in this heavily photopolluted environment, and to altitudes up to 4 km. We estimate that the installation influenced ≈1.1 million birds during our study period of 7 d over 7 y. When the installation was illuminated, birds aggregated in high densities, decreased flight speeds, followed circular flight paths, and vocalized frequently. Simulations revealed a high probability of disorientation and subsequent attraction for nearby birds, and bird densities near the installation exceeded magnitudes 20 times greater than surrounding baseline densities during each year’s observations. However, behavioral disruptions disappeared when lights were extinguished, suggesting that selective removal of light during nights with substantial bird migration is a viable strategy for minimizing potentially fatal interactions among ALAN, structures, and birds. Our results also highlight the value of additional studies describing behavioral patterns of nocturnally migrating birds in powerful lights in urban areas as well as conservation implications for such lighting installations.

scholarly journals Effects of Air Pollutants on Airway Diseases

2021 ◽  
Vol 18 (18) ◽  
pp. 9905
Author(s):  
Yun-Gi Lee ◽  
Pureun-Haneul Lee ◽  
Seon-Muk Choi ◽  
Min-Hyeok An ◽  
An-Soo Jang
Keyword(s):  
Urban Areas ◽  
Air Pollutants ◽  
Respiratory Diseases ◽  
Chronic Obstructive ◽  
Obstructive Pulmonary Disease ◽  
Airway Diseases ◽  
Biological Contaminants ◽  
Underlying Mechanisms ◽  
The Impact

Air pollutants include toxic particles and gases emitted in large quantities from many different combustible materials. They also include particulate matter (PM) and ozone, and biological contaminants, such as viruses and bacteria, which can penetrate the human airway and reach the bloodstream, triggering airway inflammation, dysfunction, and fibrosis. Pollutants that accumulate in the lungs exacerbate symptoms of respiratory diseases such as asthma and chronic obstructive pulmonary disease (COPD). Asthma, a heterogeneous disease with complex pathological mechanisms, is characterized by particular symptoms such as shortness of breath, a tight chest, coughing, and wheezing. Patients with COPD often experience exacerbations and worsening of symptoms, which may result in hospitalization and disease progression. PM varies in terms of composition, and can include solid and liquid particles of various sizes. PM concentrations are higher in urban areas. Ozone is one of the most toxic photochemical air pollutants. In general, air pollution decreases quality of life and life expectancy. It exacerbates acute and chronic respiratory symptoms in patients with chronic airway diseases, and increases the morbidity and risk of hospitalization associated with respiratory diseases. However, the mechanisms underlying these effects remain unclear. Therefore, we reviewed the impact of air pollutants on airway diseases such as asthma and COPD, focusing on their underlying mechanisms.

scholarly journals GPS tracking reveals landfill closures induce higher foraging effort and habitat switching in gulls

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Liam P. Langley ◽  
Stuart Bearhop ◽  
Niall H.K. Burton ◽  
Alex N. Banks ◽  
Tim Frayling ◽  
...  
Keyword(s):  
Habitat Selection ◽  
Urban Areas ◽  
Movement Ecology ◽  
Habitat Choice ◽  
Gps Tracking ◽  
Behavioural Responses ◽  
Larus Fuscus ◽  
Before And After ◽  
Indirect Impacts ◽  
Foraging Movements

Abstract Background Landfills are a major subsidy for some animals, with implications for their life history and demography. Gulls feed extensively on food from landfills and closures are expected to have ecological consequences, but how this influences movement ecology is virtually unknown. Methods We used GPS-tracking to quantify foraging behaviour and habitat choice of lesser black-backed gulls (Larus fuscus) breeding at two colonies before and after closure of two nearby landfills. Results Following closure, gulls from both colonies travelled further and for longer to forage. Gulls also changed habitat selection, although this differed by colony - birds from one colony shifted to agricultural habitats, while at the other, increased their use of urban areas. These behavioural responses had no effect on adult body condition but hint at potential direct effects of higher foraging costs and indirect impacts by shifting to new habitats. Conclusions Our results demonstrate how landfill availability influences gull foraging movements and habitat selection. We also emphasize the value of biologging to detect rapid behavioural responses in contrast to more conventional demographic approaches, which is especially important for animals that spend the majority of their lives away from direct observation.

scholarly journals The local hypothalamic–pituitary–adrenal axis in cultured human dermal papilla cells

2020 ◽  
Author(s):  
Eun Young Lee ◽  
You Jin Nam ◽  
Sangjin Kang ◽  
Eun Ju Choi ◽  
Inbo Han ◽  
...  
Keyword(s):  
Hpa Axis ◽  
Hair Loss ◽  
Human Hair ◽  
Stress Hormones ◽  
Dermal Papilla ◽  
Hair Shaft ◽  
Hair Follicles ◽  
Follicle Cells ◽  
Dermal Papilla Cells ◽  
Underlying Mechanisms

Abstract Background: Stress is an important cause of skin disease, including hair loss. The hormonal response to stress is due to the HPA axis, which comprises hormones such as corticotropin releasing factor (CRF) , adrenocorticotropic hormone (ACTH) , and cortisol. Many reports have shown that CRF, a crucial stress hormone, inhibits hair growth and induces hair loss. However, the underlying mechanisms are still unclear. The aim of this study was to examine the effect of CRF on human dermal papilla cells (DPCs) as well as hair follicles and to investigate whether the HPA axis was established in cultured human DPCs.Results: CRF inhibited hair shaft elongation and induced early catagen transition in human hair follicles. Hair follicle cells, both human DPCs and human ORSCs, expressed CRF and its receptors and responded to CRF. CRF inhibited the proliferation of human DPCs through cell cycle arrest at G2/M phase and induced the accumulation of reactive oxygen species (ROS) . Anagen-related cytokine levels were downregulated in CRF-treated human DPCs. Interestingly, increases in proopiomelanocortin (POMC) , ACTH, and cortisol were induced by CRF in human DPCs, and antagonists for the CRF receptor blocked the effects of this hormone. Conclusion: The results of this study showed that stress can cause hair loss by acting through stress hormones. Additionally, these results suggested that a fully functional HPA axis exists in human DPCs and that CRF directly affects human DPCs as well as human hair follicles under stress conditions.

scholarly journals Understanding urbanicity: how interdisciplinary methods help to unravel the effects of the city on mental health

2020 ◽  
pp. 1-12 ◽  
Author(s):  
Lydia Krabbendam ◽  
Mark van Vugt ◽  
Philippe Conus ◽  
Ola Söderström ◽  
Lilith Abrahamyan Empson ◽  
...  
Keyword(s):  
Mental Health ◽  
Rural Areas ◽  
Urban Areas ◽  
Mental Health Problems ◽  
Epidemiological Studies ◽  
Population Based ◽  
Urban Environments ◽  
Country Level ◽  
Underlying Causes ◽  
Underlying Mechanisms

Abstract Twenty-first century urbanization poses increasing challenges for mental health. Epidemiological studies have shown that mental health problems often accumulate in urban areas, compared to rural areas, and suggested possible underlying causes associated with the social and physical urban environments. Emerging work indicates complex urban effects that depend on many individual and contextual factors at the neighbourhood and country level and novel experimental work is starting to dissect potential underlying mechanisms. This review summarizes findings from epidemiology and population-based studies, neuroscience, experimental and experience-based research and illustrates how a combined approach can move the field towards an increased understanding of the urbanicity-mental health nexus.

scholarly journals Habitat Choice and Speciation

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Sophie E. Webster ◽  
Juan Galindo ◽  
John W. Grahame ◽  
Roger K. Butlin
Keyword(s):  
Reproductive Isolation ◽  
Local Adaptation ◽  
Ecological Speciation ◽  
Habitat Choice ◽  
Current Evidence ◽  
Evolutionary Mechanisms ◽  
Important Challenge ◽  
Intertidal Gastropod ◽  
Underlying Mechanisms

The role of habitat choice in reproductive isolation and ecological speciation has often been overlooked, despite acknowledgement of its ability to facilitate local adaptation. It can form part of the speciation process through various evolutionary mechanisms, yet where habitat choice has been included in models of ecological speciation little thought has been given to these underlying mechanisms. Here, we propose and describe three independent criteria underlying ten different evolutionary scenarios in which habitat choice may promote or maintain local adaptation. The scenarios are the result of all possible combinations of the independent criteria, providing a conceptual framework in which to discuss examples which illustrate each scenario. These examples show that the different roles of habitat choice in ecological speciation have rarely been effectively distinguished. Making such distinctions is an important challenge for the future, allowing better experimental design, stronger inferences and more meaningful comparisons among systems. We show some of the practical difficulties involved by reviewing the current evidence for the role of habitat choice in local adaptation and reproductive isolation in the intertidal gastropodLittorina saxatilis, a model system for the study of ecological speciation, assessing whether any of the proposed scenarios can be reliably distinguished, given current research.

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