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Gonzalez-Gomez PL, Villavicencio CP, Quispe R, Schwabl P, Cornelius JM, Ramenofsky M, Krause JS, Wingfield JC. Perspectives on environmental heterogeneity and seasonal modulation of stress response in neotropical birds. Horm Behav 2023; 152:105359. [PMID: 37058919 DOI: 10.1016/j.yhbeh.2023.105359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/27/2023] [Accepted: 03/31/2023] [Indexed: 04/16/2023]
Abstract
Corticosterone (CORT), the main glucocorticoid in birds, regulates physiological and behavioral traits linked to predictable and unpredictable environmental fluctuations (i.e., stressors). Baseline and stress-induced CORT concentrations are known to fluctuate seasonally, linked to life history stages (LHS) such as breeding, molt, and wintering stage. These variations have been relatively well described in North American birds, but poorly addressed in neotropical species. To fill this gap, we explored how baseline and stress-induced CORT variation by LHS was affected by seasonality and environmental heterogeneity (i.e., frequency of unpredictable events such as droughts, flashfloods, etc) within the Neotropics using two approaches. First, we reviewed all currently available data about CORT concentrations for neotropical bird species. Second, we performed an in-depth analysis comparing the CORT responses of the two most common species of the Zonotrichia genus from North and South America (Z. leucophrys and Z. capensis, respectively) and their subspecies to seasonality and environmental heterogeneity. These species have been analyzed with the same methodology, allowing for an in-depth comparison of CORT variations. Despite scant data on neotropical bird species, we observed overlap between molt and breeding, and lower fluctuations of CORT among LHS. These patterns would be considered atypical compared to those described for North temperate species. Further, we found no significant associations between environmental heterogeneity and the stress-responses. In Zonotrichia we observed a positive association between baseline and stress-induced concentrations of CORT and latitude. We also observed differences by LHS. Both baseline and stress-induced CORT concentrations were higher during breeding and lower during molt. In addition, for both species, the overall pattern of seasonal modulation of stress response was heavily influenced by the migration strategy, with long-distance migrants showing significantly higher stress-induced CORT levels. Our results highlight the need for more data collection in the Neotropics. Comparative data would shed further light on the sensitivity of the adrenocortical response to stress under different scenarios of environmental seasonality and unpredictability.
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Affiliation(s)
- Paulina L Gonzalez-Gomez
- Department of Wildlife, Fish, and Conservation Biology, University of California Davis, One Shields Ave, Davis, CA 95616, USA; Universidad Autónoma de Chile, Av. Pedro de Valdivia 425, Providencia, Santiago, Chile.
| | - Camila P Villavicencio
- IEB, Facultad de Ciencias, Universidad de Chile, Las Palmeras 3425, Ñuñoa, Santiago, Chile
| | - Rene Quispe
- Departamento de Ciencias Biológicas Animales, Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santa Rosa 11735, Santiago, Chile
| | - Philipp Schwabl
- Insitute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, United Kingdom
| | | | - Marilyn Ramenofsky
- Department of Neurobiology, Physiology and Behavior, University of California Davis, USA
| | - Jesse S Krause
- Department of Neurobiology, Physiology and Behavior, University of California Davis, USA
| | - John C Wingfield
- Department of Neurobiology, Physiology and Behavior, University of California Davis, USA
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McQueen A, Kempenaers B, Dale J, Valcu M, Emery ZT, Dey CJ, Peters A, Delhey K. Evolutionary drivers of seasonal plumage colours: colour change by moult correlates with sexual selection, predation risk and seasonality across passerines. Ecol Lett 2019; 22:1838-1849. [PMID: 31441210 DOI: 10.1111/ele.13375] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2019] [Accepted: 07/22/2019] [Indexed: 12/12/2022]
Abstract
Some birds undergo seasonal colour change by moulting twice each year, typically alternating between a cryptic, non-breeding plumage and a conspicuous, breeding plumage ('seasonal plumage colours'). We test for potential drivers of the evolution of seasonal plumage colours in all passerines (N = 5901 species, c. 60% of all birds). Seasonal plumage colours are uncommon, having appeared on multiple occasions but more frequently lost during evolution. The trait is more common in small, ground-foraging species with polygynous mating systems, no paternal care and strong sexual dichromatism, suggesting it evolved under strong sexual selection and high predation risk. Seasonal plumage colours are also more common in species predicted to have seasonal breeding schedules, such as migratory birds and those living in seasonal climates. We propose that seasonal plumage colours have evolved to resolve a trade-off between the effects of natural and sexual selection on colouration, especially in seasonal environments.
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Affiliation(s)
- Alexandra McQueen
- School of Biological Sciences, Monash University, VIC, Clayton Campus, 3800, Australia
| | - Bart Kempenaers
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard Gwinner Str, 82319, Seewiesen, Germany
| | - James Dale
- Institute of Natural and Mathematical Sciences, Massey University, Auckland, 0745, New Zealand
| | - Mihai Valcu
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Eberhard Gwinner Str, 82319, Seewiesen, Germany
| | - Zachary T Emery
- School of Biological Sciences, Monash University, VIC, Clayton Campus, 3800, Australia
| | - Cody J Dey
- Great Lakes Institute for Environmental Research, University of Windsor, 401 Sunset Avenue, Windsor, ON, Canada
| | - Anne Peters
- School of Biological Sciences, Monash University, VIC, Clayton Campus, 3800, Australia
| | - Kaspar Delhey
- School of Biological Sciences, Monash University, VIC, Clayton Campus, 3800, Australia
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Injaian AS, Gonzalez-Gomez PL, Taff CC, Bird AK, Ziur AD, Patricelli GL, Haussmann MF, Wingfield JC. Traffic noise exposure alters nestling physiology and telomere attrition through direct, but not maternal, effects in a free-living bird. Gen Comp Endocrinol 2019; 276:14-21. [PMID: 30796896 DOI: 10.1016/j.ygcen.2019.02.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 02/13/2019] [Accepted: 02/19/2019] [Indexed: 12/26/2022]
Abstract
Anthropogenic impacts, such as noise pollution from transportation networks, can serve as stressors to some wildlife species. For example, increased exposure to traffic noise has been found to alter baseline and stress-induced corticosterone levels, reduce body condition and reproductive success, and increase telomere attrition in free-living birds. However, it remains unknown if alterations in nestling phenotype are due to direct or indirect effects of noise exposure. For example, indirect (maternal) effects of noise may occur if altered baseline and stress-induced corticosterone in mothers results in differential deposition of yolk steroids or other components in eggs. Noise exposure may also alter nestling corticosterone levels directly, given that nestlings cannot escape the nest during development. Here, we examined maternal versus direct effects of traffic noise exposure on baseline and stress-induced corticosterone levels, and body condition (as measured by size-corrected mass) in nestling tree swallows (Tachycineta bicolor). We used a two-way factorial design and partially cross-fostered eggs between nests exposed to differing levels (i.e. amplitudes) of traffic noise. For nestlings that were not cross-fostered, we also investigated the effects of traffic noise on telomere dynamics. Our results show a positive relationship between nestling baseline and stress-induced corticosterone and nestling noise exposure, but not maternal noise exposure. While we did not find a relationship between noise and body condition in nestlings, nestling baseline corticosterone was negatively associated with body condition. We also found greater telomere attrition for nestlings from nests with greater traffic noise amplitudes. These results suggest that direct, rather than maternal, effects result in potentially long-lasting consequences of noise exposure. Reduced nestling body condition and increased telomere attrition have been shown to reduce post-fledging survival in this species. Given that human transportation networks continue to expand, strategies to mitigate noise exposure on wildlife during critical periods (i.e. breeding) may be needed to maintain local population health in free-living passerines, such as tree swallows.
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Affiliation(s)
- Allison S Injaian
- Department of Ecology and Evolution, University of California Davis, One Shields Avenue, Davis, CA 95616, USA.
| | - Paulina L Gonzalez-Gomez
- Department of Neurobiology, Physiology and Behavior, University of California Davis, One Shields Avenue, Davis, CA 95616, USA; Universidad Autónoma de Chile, Providencia 425, Santiago, Chile
| | - Conor C Taff
- Cornell Lab of Ornithology, 159 Sapsucker Woods Road, Ithaca, NY 14850, USA
| | - Alicia K Bird
- Department of Ecology and Evolution, University of California Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Alexis D Ziur
- Department of Biology, Bucknell University, 701 Moore Ave, Lewisburg, PA 17837, USA
| | - Gail L Patricelli
- Department of Ecology and Evolution, University of California Davis, One Shields Avenue, Davis, CA 95616, USA
| | - Mark F Haussmann
- Department of Biology, Bucknell University, 701 Moore Ave, Lewisburg, PA 17837, USA
| | - John C Wingfield
- Department of Neurobiology, Physiology and Behavior, University of California Davis, One Shields Avenue, Davis, CA 95616, USA
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Quispe R, Yohannes E, Gahr M. Seasonality at the equator: isotope signatures and hormonal correlates of molt phenology in a non-migratory Amazonian songbird. Front Zool 2018; 15:39. [PMID: 30386404 PMCID: PMC6205779 DOI: 10.1186/s12983-018-0284-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 09/25/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Birds, across their annual cycle, progress through sequences of life-history stages such as reproduction and molt. The mechanisms that control annual avian itineraries involve endocrine responses triggered by seasonal environmental factors, including changes in resource availability and/or photoperiod. However, at equatorial latitudes birds are exposed to different degrees of seasonality, and the mechanisms underlying phenology of birds near the equator remain less explored. We studied the silver-beaked tanager, an endemic Amazonian songbird, from an equatorial lowland population. Remarkably, in this species, song behavior has been shown to be seasonally aligned to minimal changes in day length near the equator. Here, we aimed to further explore the phenology of silver-beaked tanagers by assessing shifts of food sources utilization as potential ultimate factors. We measured triple isotopic tracers of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) in blood and feathers of birds throughout a whole year. In addition, we assessed the degree of seasonality in the molting activity, in relation to circulating levels of corticosterone, as well as to testosterone as a proxy of the reproductive condition of males. RESULTS There was important seasonal variation of δ34S values in relation to rainfall patterns and changes in estuarine water composition. Despite the seasonal rainfall, we found no substantial variation in the foraging ecology of birds over seasons. This was accompanied by uniform levels of corticosterone throughout the year, probably associated with the absence of drastic seasonal resource shortages. Even so, silver-beaked tanagers showed a marked seasonal molting schedule, which was related to variation in the circulating levels of both corticosterone and testosterone. CONCLUSIONS These findings suggest that foraging niche is not life history stage-dependent in silver-beaked tanagers, and highlight rainfall as an important environmental cue for bird phenology. Our stable isotope results encourage further studies addressing the influence of estuarine water dynamics on bird timing. In addition, the results suggest a primary role of steroid hormones in regulating seasonal life history stages under the absence of a marked photoperiod. Contrary to what might be expected for a tropical songbird, our physiological data in silver-beaked tanagers do not support reproduction-molt overlapping.
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Affiliation(s)
- Rene Quispe
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Strasse, Seewiesen, 82319 Germany
- Present address: Departamento Biología Marina, Facultad Ciencias del Mar, Universidad Católica del Norte, Coquimbo, Chile
| | - Elizabeth Yohannes
- Stable Isotope Lab, Limnological Institute, University of Constance, Konstanz, Germany
| | - Manfred Gahr
- Department of Behavioural Neurobiology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Strasse, Seewiesen, 82319 Germany
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González‐Gómez PL, Echeverria V, Estades CF, Perez JH, Krause JS, Sabat P, Li J, Kültz D, Wingfield JC. Contrasting seasonal and aseasonal environments across stages of the annual cycle in the rufous‐collared sparrow,
Zonotrichia capensis
: Differences in endocrine function, proteome and body condition. J Anim Ecol 2018; 87:1364-1382. [DOI: 10.1111/1365-2656.12846] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Accepted: 03/29/2018] [Indexed: 01/07/2023]
Affiliation(s)
- Paulina L. González‐Gómez
- Department of Neurobiology, Physiology and Behavior University of California Davis Davis California
- Universidad Autónoma de Chile Providencia Santiago Chile
| | - Valentina Echeverria
- Departamento de Manejo de Recursos Naturales Facultad de Ciencias Forestales y Conservación de la Naturaleza Universidad de Chile La Pintana Santiago Chile
| | - Cristian F. Estades
- Departamento de Manejo de Recursos Naturales Facultad de Ciencias Forestales y Conservación de la Naturaleza Universidad de Chile La Pintana Santiago Chile
| | - Jonathan H. Perez
- Department of Neurobiology, Physiology and Behavior University of California Davis Davis California
| | - Jesse S. Krause
- Department of Neurobiology, Physiology and Behavior University of California Davis Davis California
| | - Pablo Sabat
- IEB Facultad de Ciencias Universidad de Chile Ñuñoa Santiago Chile
- Center of Applied Ecology and Sustainability (CAPES) Pontificia Universidad Católica de Chile Santiago Chile
| | - Jonathon Li
- Biochemical Evolution Laboratory Department of Animal Science University of California Davis Davis California
| | - Dietmar Kültz
- Biochemical Evolution Laboratory Department of Animal Science University of California Davis Davis California
| | - John C. Wingfield
- Department of Neurobiology, Physiology and Behavior University of California Davis Davis California
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Escallón C, Weinstein NM, Tallant JA, Wojtenek W, Rodríguez-Saltos CA, Bonaccorso E, Moore IT. Testosterone and Haemosporidian Parasites Along a Tropical Elevational Gradient in Rufous-Collared Sparrows (Zonotrichia capensis). JOURNAL OF EXPERIMENTAL ZOOLOGY. PART A, ECOLOGICAL GENETICS AND PHYSIOLOGY 2016; 325:501-510. [PMID: 27527346 DOI: 10.1002/jez.2034] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2016] [Revised: 07/25/2016] [Accepted: 07/26/2016] [Indexed: 11/09/2022]
Abstract
Elevation has been proposed as a dominant ecological variable shaping life history traits and subsequently their underlying hormonal mechanisms. In an earlier meta-analysis of tropical birds, elevation was positively related to testosterone levels. Furthermore, parasitism by avian haemosporidians should vary with elevation as environmental conditions affect vector abundance, and while testosterone is needed for breeding, it is hypothesized to be immunosuppressive and thus could exacerbate haemosporidian infection. Our objective in this study was to examine the relationships between elevation, testosterone levels, and parasitism by avian haemosporidians. We surveyed breeding male rufous-collared sparrows (Zonotrichia capensis) across a wide elevational range along the equator. We measured baseline testosterone levels, haemosporidian infection at four elevations spanning the species' natural range in the Ecuadorian Andes (600, 1500, 2100, 3300 m). Testosterone levels from breeding males were not related to elevation, but there was high intrapopulation variability. Testosterone levels were not related to the probability of parasitism, but our results from one population suggested that the likelihood of being infected by haemosporidian parasites was greater when in breeding condition. In conclusion, even though there is variation in life history strategies among the studied populations, wider divergence in seasonality and life history traits would probably be needed to detect an effect of elevation on testosterone if one exists. Additionally, our results show that variation in testosterone is not related to infection risk of haemosporidians, thus other factors that take a toll on energetic resources, such as reproduction, should be looked at more closely.
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Affiliation(s)
- Camilo Escallón
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia.
| | - Nicole M Weinstein
- VA-MD Regional College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia
| | - James A Tallant
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia
| | | | | | - Elisa Bonaccorso
- Centro de Investigación de la Biodiversidad y Cambio Climático (BioCamb) e Ingenieriía en Biodiversidad y Recursos Genéticos, Facultad de Ciencias de Medio Ambiente, Universidad Tecnológica Indoamérica, Machala y Sabanilla, Cotocollao, Quito, Ecuador
| | - Ignacio T Moore
- Department of Biological Sciences, Virginia Tech, Blacksburg, Virginia
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Buttemer WA, Addison BA, Astheimer LB. Lack of seasonal and moult-related stress modulation in an opportunistically breeding bird: The white-plumed honeyeater (Lichenostomus penicillatus). Horm Behav 2015; 76:34-40. [PMID: 25701624 DOI: 10.1016/j.yhbeh.2015.02.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 02/07/2015] [Accepted: 02/10/2015] [Indexed: 11/17/2022]
Abstract
This article is part of a Special Issue "SBN 2014". In most vertebrate species, glucocorticoid levels and stress sensitivity vary in relation to season and life-history stage. In birds, baseline corticosterone (CORT) and stress sensitivity are typically highest while breeding and decrease substantially during moult. Because elevated CORT adversely affects protein synthesis, moult-related CORT suppression is thought to be necessary for forming high-quality feathers. Surprisingly, some passerine species lack moult-related CORT suppression, but these are distinguished by having slow rates of moult and being opportunistic breeders. We examined baseline and stress-induced CORT levels in an opportunistically breeding Australian passerine, the white-plumed honeyeater (Lichenostomus penicillatus). Although this species has a slower moult rate than high-latitude breeders, it differs little from north-temperate passerines. Neither baseline nor stress-induced CORT levels varied with season (winter, spring or summer), sex or moult status in adult birds. While breeding tended to be highest in early spring through late summer, laparotomies revealed only limited reduction in testicular size in males the year round. In all but one sampling period, at least some females displayed follicular hierarchy. Breeding usually coincides with outbreaks of phytophagous insects, which can happen at any time of the year. This results in moult/breeding overlap when infestations occur in late spring or summer. The ability of this species to moult and breed at the same time while having breeding-levels of CORT demonstrates that CORT suppression is not a prerequisite for synthesis of high-quality feathers. An experimental design incorporating moulting and non-moulting phenotypes is suggested to test the functional significance of CORT suppression in other species.
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Affiliation(s)
- William A Buttemer
- Centre for Integrative Ecology, Deakin University, Geelong, Victoria, Australia.
| | - BriAnne A Addison
- Centre for Integrative Ecology, Deakin University, Geelong, Victoria, Australia
| | - Lee B Astheimer
- Centre for Integrative Ecology, Deakin University, Geelong, Victoria, Australia
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Small TW, Brenowitz EA, Wojtenek W, Moore IT. Testosterone Mediates Seasonal Growth of the Song Control Nuclei in a Tropical Bird. BRAIN, BEHAVIOR AND EVOLUTION 2015; 86:110-21. [PMID: 26346733 DOI: 10.1159/000437412] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 06/24/2015] [Indexed: 11/19/2022]
Abstract
In mid- to high-latitude songbirds, seasonal reproduction is stimulated by increasing day length accompanied by elevated plasma sex steroid levels, increased singing, and growth of the song control nuclei (SCN). Plasticity of the SCN and song behavior are primarily mediated by testosterone (T) and its metabolites in most species studied thus far. However, the majority of bird species are tropical and have less pronounced seasonal reproductive cycles. We have previously documented that equatorial rufous-collared sparrows (Zonotrichia capensis) exhibit seasonal neuroplasticity in the SCN. Manipulating T in these birds, however, did not alter singing behavior. In the current study, we investigated whether T mediates plasticity of the SCN in a similar manner to temperate songbirds. In the first experiment, we treated captive male birds with T or blank implants during the nonbreeding season. In a second experiment, we treated captive male birds with either blank implants, T-filled implants, T with flutamide (FLU; an androgen receptor antagonist) or T with FLU and 1,4,6-androstatriene-3,17-dione (ATD; an estrogen synthesis inhibitor) during the breeding season. In both experiments, the volumes of the brain areas high vocal center (HVC), Area X, and robust nucleus of the arcopallium (RA) were measured along with singing behavior. In summary, T stimulated growth of HVC and RA, and the combined effect of FLU and ATD reversed this effect in HVC. Area X was not affected by T treatment in either experiment. Neither T-treated birds nor controls sang in captivity during either experiment. Together, these data indicate that T mediates seasonal changes in the HVC and RA of both tropical and higher- latitude bird species even if the environmental signals differ. However, unlike most higher-latitude songbirds, we found no evidence that motivation to sing or growth of Area X are stimulated by T under captive conditions.
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Affiliation(s)
- Thomas W Small
- Department of Biological Sciences, Virginia Tech, Blacksburg, Va., USA
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9
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Merrill L, González-Gómez PL, Ellis VA, Levin II, Vásquez RA, Wingfield JC. A blurring of life-history lines: Immune function, molt and reproduction in a highly stable environment. Gen Comp Endocrinol 2015; 213:65-73. [PMID: 25712433 DOI: 10.1016/j.ygcen.2015.02.010] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Revised: 01/26/2015] [Accepted: 02/14/2015] [Indexed: 10/24/2022]
Abstract
Rufous-collared sparrows (Zonotrichia capensis peruviensis) from valleys in the Atacama Desert of Chile, live in an extremely stable environment, and exhibit overlap in molt and reproduction, with valley-specific differences in the proportion of birds engaged in both. To better understand the mechanistic pathways underlying the timing of life-history transitions, we examined the relationships among baseline and stress-induced levels of corticosterone (CORT), testosterone, and bacteria-killing ability of the blood plasma (BKA), as well as haemosporidian parasite infections and the genetic structure of two groups of sparrows from separate valleys over the course of a year. Birds neither molting nor breeding had the lowest BKA, but there were no differences among the other three categories of molt-reproductive stage. BKA varied over the year, with birds in May/June exhibiting significantly lower levels of BKA than the rest of the year. We also documented differences in the direction of the relationship between CORT and BKA at different times during the year. The direction of these relationships coincides with some trends in molt and reproductive stage, but differs enough to indicate that these birds exhibit individual-level plasticity, or population-level variability, in coordinating hypothalamo-pituitary-adrenal axis activity with life-history stage. We found weak preliminary evidence for genetic differentiation between the two populations, but not enough to indicate genetic isolation. No birds were infected with haemosporidia, which may be indicative of reduced parasite pressure in deserts. The data suggest that these birds may not trade off among different life-history components, but rather are able to invest in multiple life-history components based on their condition.
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Affiliation(s)
- Loren Merrill
- Illinois Natural History Survey, University of Illinois, Urbana-Champaign, IL 61820, USA.
| | | | - Vincenzo A Ellis
- Department of Biology, University of Missouri, St. Louis, MO 63121, USA.
| | - Iris I Levin
- Department of Biology, Grinnell College, Grinnell, IA 50112, USA; Department of Ecology and Evolutionary Biology, University of Colorado at Boulder, Boulder, CO 80309, USA(1).
| | - Rodrigo A Vásquez
- Instituto de Ecología y Biodiversidad, IEB, Universidad de Chile, Santiago, Chile.
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Imai M, Miyazaki M, Yeung HH, Hidaka S, Kantartzis K, Okada H, Kita S. Sound symbolism facilitates word learning in 14-month-olds. PLoS One 2015; 10:e0116494. [PMID: 25695741 PMCID: PMC4335030 DOI: 10.1371/journal.pone.0116494] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2013] [Accepted: 12/10/2014] [Indexed: 11/18/2022] Open
Abstract
Sound symbolism, or the nonarbitrary link between linguistic sound and meaning, has often been discussed in connection with language evolution, where the oral imitation of external events links phonetic forms with their referents (e.g., Ramachandran & Hubbard, 2001). In this research, we explore whether sound symbolism may also facilitate synchronic language learning in human infants. Sound symbolism may be a useful cue particularly at the earliest developmental stages of word learning, because it potentially provides a way of bootstrapping word meaning from perceptual information. Using an associative word learning paradigm, we demonstrated that 14-month-old infants could detect Köhler-type (1947) shape-sound symbolism, and could use this sensitivity in their effort to establish a word-referent association.
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Affiliation(s)
- Mutsumi Imai
- Department of Environment and Information Studies, Keio University, 5322 Endo, Fujisawa, Kanagawa, 252–8520, Japan
| | - Michiko Miyazaki
- School of Social Information Studies, Otsuma Women’s University, 2–7–1, Karakida, Tama-city, Tokyo, 206–8540, Japan
- Brain Science Institute, Tamagawa University, 6–1–1, Tamagawa-gakuen, Machida-city, Tokyo, 194–8610, Japan
| | - H. Henny Yeung
- Centre National de la Recherche Scientifique, Paris, France & Laboratoire Psychologie de la Perception, Université Paris Descartes, Paris Sorbonne Cité, Paris, France
| | - Shohei Hidaka
- School of Knowledge Science, Japan Advanced Institute of Science and Technology, 1–1 Asahidai, Nomi, Ishikawa, 923–1292, Japan
| | - Katerina Kantartzis
- School of Psychology, University of Birmingham, B15 2TT, Birmingham, United Kingdom
| | - Hiroyuki Okada
- Brain Science Institute, Tamagawa University, 6–1–1, Tamagawa-gakuen, Machida-city, Tokyo, 194–8610, Japan
| | - Sotaro Kita
- Department of Psychology, University of Warwick, Coventry, United Kingdom
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