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152 records – page 1 of 16.

Activity budgets and activity rhythms in red ruffed lemurs (Varecia rubra) on the Masoala Peninsula, Madagascar: seasonality and reproductive energetics.

https://arctichealth.org/en/permalink/ahliterature95795
Source
Am J Primatol. 2005 May;66(1):23-44
Publication Type
Article
Date
May-2005
Author
Vasey Natalie
Author Affiliation
Department of Anthropology, Portland State University, Portland, Oregon 97207-0751, USA. nvasey@pdx.edu
Source
Am J Primatol. 2005 May;66(1):23-44
Date
May-2005
Language
English
Publication Type
Article
Keywords
Activity Cycles - physiology
Animals
Ecosystem
Energy Metabolism - physiology
Feeding Behavior - physiology
Lemuridae - physiology
Madagascar
Motor Activity - physiology
Observation
Reproduction - physiology
Seasons
Sex Factors
Abstract
The activity budgets and daily activity rhythms of Varecia rubra were examined over an annual cycle according to season and reproductive stage. Given the relatively high reproductive costs and patchy food resources of this species, I predicted that V. rubra would 1) travel less and feed more during seasonal resource scarcity in an attempt to maintain energy balance, and 2) show sex differences in activity budgets due to differing reproductive investment. Contrary to the first prediction, V. rubra does not increase feeding time during seasonal food scarcity; rather, females feed for a consistent amount of time in every season, whereas males feed most during the resource-rich, hot dry season. The results are consistent with other predictions: V. rubra travels less in the resource-scarce cold rainy season, and there are some pronounced sex differences, with females feeding more and resting less than males in every season and in every reproductive stage except gestation. However, there are also some provocative similarities between the sexes when activity budgets are examined by reproductive stage. During gestation, female and male activity budgets do not differ and appear geared toward energy accumulation: both sexes feed and rest extensively and travel least during this stage. During lactation, activity budgets are geared toward high energy expenditure: both sexes travel most and in equal measure, and rest least, although it remains the case that females feed more and rest less than males. These similarities between female and male activity budgets appear related to cooperative infant care. The high energetic costs of reproduction in V. rubra females may require that they allot more time to feeding year round, and that their overall activity budget be more directly responsive to seasonal climate change, seasonal food distribution, and reproductive schedules.
Notes
Erratum In: Am J Primatol. 2005 Aug;66(4):393-4
PubMed ID
15898071 View in PubMed
Less detail
Source
Evolution. 2004 Aug;58(8):1748-62
Publication Type
Article
Date
Aug-2004
Author
Bradshaw William E
Zani Peter A
Holzapfel Christina M
Author Affiliation
Center for Ecology and Evolutionary Biology, University of Oregon, Eugene, Oregon 97403-5289, USA. bradshaw@darkwing.uoregon.edu
Source
Evolution. 2004 Aug;58(8):1748-62
Date
Aug-2004
Language
English
Publication Type
Article
Keywords
Adaptation, Physiological
Animals
Climate
Culicidae - genetics - physiology
Environment, Controlled
Evolution
Geography
North America
Photoperiod
Reproduction - physiology
Selection (Genetics)
Temperature
Abstract
Only model organisms live in a world of endless summer. Fitness at temperate latitudes reflects the ability of organisms in nature to exploit the favorable season, to mitigate the effects of the unfavorable season, and to make the timely switch from one life style to the other. Herein, we define fitness as Ry, the year-long cohort replacement rate across all four seasons, of the mosquito, Wyeomyia smithii, reared in its natural microhabitat in processor-controlled environment rooms. First, we exposed cohorts of W. smithii, from southern, midlatitude, and northern populations (30-50 degrees N) to southern and northern thermal years during which we factored out evolved differences in photoperiodic response. We found clear evidence of evolved differences in heat and cold tolerance among populations. Relative cold tolerance of northern populations became apparent when populations were stressed to the brink of extinction; relative heat tolerance of southern populations became apparent when the adverse effects of heat could accumulate over several generations. Second, we exposed southern, midlatitude, and northern populations to natural, midlatitude day lengths in a thermally benign midlatitude thermal year. We found that evolved differences in photoperiodic response (1) prevented the timely entry of southern populations into diapause resulting in a 74% decline in fitness, and (2) forced northern populations to endure a warm-season diapause resulting in an 88% decline in fitness. We argue that reciprocal transplants across latitudes in nature always confound the effects of the thermal and photic environment on fitness. Yet, to our knowledge, no one has previously held the thermal year constant while varying the photic year. This distinction is crucial in evaluating the potential impact of climate change. Because global warming in the Northern Hemisphere is proceeding faster at northern than at southern latitudes and because this change represents an amelioration of the thermal environment and a concomitant increase in the duration of the growing season, we conclude that there should be more rapid evolution of photoperiodic response than of thermal tolerance as a consequence of global warming among northern, temperate ectotherms.
PubMed ID
15446427 View in PubMed
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Adaptive variation in senescence: reproductive lifespan in a wild salmon population.

https://arctichealth.org/en/permalink/ahliterature6679
Source
Proc Biol Sci. 2004 Feb 7;271(1536):259-66
Publication Type
Article
Date
Feb-7-2004
Author
Andrew P Hendry
Yolanda E Morbey
Ole K Berg
John K Wenburg
Author Affiliation
Redpath Museum and Department of Biology, McGill University, Montréal, Québec, Canada. andrew.hendry@mcgill.ca
Source
Proc Biol Sci. 2004 Feb 7;271(1536):259-66
Date
Feb-7-2004
Language
English
Publication Type
Article
Keywords
Adaptation, Physiological
Age Factors
Aging - physiology
Alaska
Animals
Body Composition
Comparative Study
Female
Game Theory
Genetics, Population
Microsatellite Repeats - genetics
Models, Biological
Nesting Behavior - physiology
Reproduction - physiology
Research Support, Non-U.S. Gov't
Salmon - physiology
Selection (Genetics)
Abstract
The antagonistic pleiotropy theory of senescence postulates genes or traits that have opposite effects on early-life and late-life performances. Because selection is generally weaker late in life, genes or traits that improve early-life performance but impair late-life performance should come to predominate. Variation in the strength of age-specific selection should then generate adaptive variation in senescence. We demonstrate this mechanism by comparing early and late breeders within a population of semelparous capital-breeding sockeye salmon (Oncorhynchus nerka). We show that early breeders (but not late breeders) are under strong selection for a long reproductive lifespan (RLS), which facilitates defence of their nests against disturbance by later females. Accordingly, early females invest less energy in egg production while reserving more for nest defence. Variation along this reproductive trade-off causes delayed or slower senescence in early females (average RLS of 26 days) than in late females (reproductive lifespan of 12 days). We use microsatellites to confirm that gene flow is sufficiently limited between early and late breeders to allow adaptive divergence in response to selection. Because reproductive trade-offs should be almost universal and selection acting on them should typically vary in time and space, the mechanism described herein may explain much of the natural variation in senescence.
PubMed ID
15058436 View in PubMed
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Advantage of specialism: reproductive output is related to prey choice in a small raptor.

https://arctichealth.org/en/permalink/ahliterature271544
Source
Oecologia. 2015 Sep;179(1):129-37
Publication Type
Article
Date
Sep-2015
Author
Andreas Otterbeck
Andreas Lindén
Éric Roualet
Source
Oecologia. 2015 Sep;179(1):129-37
Date
Sep-2015
Language
English
Publication Type
Article
Keywords
Animals
Choice Behavior - physiology
Diet
Falconiformes - growth & development - physiology
Female
Male
Norway
Population Density
Predatory Behavior - physiology
Reproduction - physiology
Species Specificity
Abstract
Predatory species' usage of different prey types is affected by both prey availability and selectivity. The diet during the breeding season may affect the reproductive success of individual pairs. We studied the prey use of a small reversed size-dimorphic raptor, the Eurasian sparrowhawk Accipiter nisus, with respect to prey weight on two organizational levels. Using 13 years of data from southern Norway, we related reproductive output of individual breeding events to prey size taken. Further, we assessed the regional variation in prey usage between five Fennoscandian populations. This was done by fitting optimum-type functions to the prey species' numbers or relative predation risks. Pairs that successfully completed the season with more fledglings displayed less variation in prey size, suggesting a possible adaptive benefit of diet specialism, or possibly a correlative effect due to higher prey availability or lower female hunting effort. This finding contrasts with earlier raptor studies, which have suggested benefits of dietary (and hence nutritional) diversity. Indeed, our results might be limited to nutritionally substitutable prey items. We also found a tendency suggesting that older females raised more fledglings than 1-year-old females. In the population-level analysis, we found that optimum-type functions with constant width and spatially variable average best described the relationship between relative predation risk and log weight. This can reflect local conditions, such as prey availability. Our findings and new methodological tools could apply to a broader spectrum of predators. They also highlight the role of viewing usage or choice of prey at several spatial scales.
PubMed ID
25943192 View in PubMed
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Age- and sex-related differences in opioid receptor densities in the songbird vocal control system.

https://arctichealth.org/en/permalink/ahliterature6796
Source
J Comp Neurol. 1999 Feb 22;404(4):505-14
Publication Type
Article
Date
Feb-22-1999
Author
C C Gulledge
P. Deviche
Author Affiliation
Institute of Arctic Biology, University of Alaska Fairbanks, 99775-7000, USA. cgulledg@emerald.tufts.edu
Source
J Comp Neurol. 1999 Feb 22;404(4):505-14
Date
Feb-22-1999
Language
English
Publication Type
Article
Keywords
Aging - physiology
Analgesics, Opioid - pharmacology
Animals
Autoradiography
Enkephalin, Ala(2)-MePhe(4)-Gly(5)-
Enkephalin, D-Penicillamine (2,5)-
Enkephalins - pharmacology
Female
Image Processing, Computer-Assisted
Male
Receptors, Opioid - physiology
Receptors, Opioid, delta - agonists - physiology
Receptors, Opioid, mu - agonists - physiology
Reproduction - physiology
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Research Support, U.S. Gov't, P.H.S.
Sex Characteristics
Songbirds - physiology
Vocalization, Animal - physiology
Abstract
Avian vocal control regions of adult male songbirds contain opioid peptides and receptors, suggesting that opioids play a role in avian vocal behavior control. In a previous study, we found no difference in opioid receptor densities in singing versus nonsinging adult male dark-eyed juncos (Junco hyemalis), leading us to hypothesize that opioids are not involved in controlling song production. To assess whether opioids may be involved in other aspects of vocal behavior, we used quantitative in vitro autoradiography to compare mu and delta opioid receptor densities in vocal control regions of singing adult males with those of adult females and adolescent (about 3 months old) males and females. We found mu and delta receptors in all vocal control regions measured. Adolescents had significantly higher opioid receptor densities than did adults in area X (delta), robust n. of the archistriatum (delta and mu), and n. intercollicularis (mu), suggesting a developmental role for opioids in the vocal control system. Based on opioid roles in other animal models, we propose that opioids may be involved in song learning, auditory processing, and/or vocal control system development.
PubMed ID
9987994 View in PubMed
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[A genetic-demographic study of the South Altaian population of the Mendur-Sokkon village (Altai Republic)]

https://arctichealth.org/en/permalink/ahliterature34025
Source
Genetika. 1997 Nov;33(11):1559-64
Publication Type
Article
Date
Nov-1997
Author
L P Osipova
Iu O Kashinskaia
O L Posukh
E A Ivakin
Iu A Kriukov
Author Affiliation
Institute of Cytology and Genetics, Siberian Division, Russian Academy of Sciences, Novosibirsk, Russia.
Source
Genetika. 1997 Nov;33(11):1559-64
Date
Nov-1997
Language
Russian
Publication Type
Article
Keywords
Adolescent
Adult
Child
Child, Preschool
Demography
English Abstract
Ethnic Groups - genetics
Female
Genetics, Population
Humans
Infant
Infant, Newborn
Male
Middle Aged
Reproduction - physiology
Rural Population
Russia
Transients and Migrants
Abstract
The main demographic parameters of the population of South Altaians from the Mendur-Sokkon village, Ust'-Kanskii raion, Altai Republic, were studied. This population was classified as a growing one because the population's reproductive size was large (37%), the prereproductive part constituted the majority of the population (52%), and the average number of surviving children per spouse was 2.6. The population studied began to mix with other ethnic groups (mostly Russians and Kazakhs) only recently; therefore, the proportion of interethnic hybrids was only 5%. The tribal structure of the Mendur-Sokkon population was typical of all South Altaians and characterized by stringent observance of exogamous regulations. An ethnically pure core was preserved in the population. The degree of endogamy was 0.36; however, the population mostly exchanged marriage migrants within the Ust'-Kanskii raion. A study of postreproductive females revealed that the average number of surviving children and pregnancies per female was 4.9 and 5.3, respectively; these values were lower than those in indigenous northern Siberian populations studied earlier. The high value of the Crow's index of total selection (Itot = 0.63) was mainly accounted for by the differential fecundity component, I(f) = 0.40, whereas the prereproductive mortality component (Im = 0.16) was considerably lower than in northern Siberian populations (Nganasans, Forest and Tundra Nentsi, Evens, Asian Eskimos, etc.) and closer to the values characteristic of urban human populations.
PubMed ID
9480220 View in PubMed
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Allocating protein to reproduction in arctic reindeer and caribou.

https://arctichealth.org/en/permalink/ahliterature92511
Source
Physiol Biochem Zool. 2008 Nov-Dec;81(6):835-55
Publication Type
Article
Author
Barboza Perry S
Parker Katherine L
Author Affiliation
Department of Biology and Wildlife, Institute of Arctic Biology, University of Alaska, Fairbanks, Alaska 99775-7000, USA. ffpsb@uaf.edu
Source
Physiol Biochem Zool. 2008 Nov-Dec;81(6):835-55
Language
English
Publication Type
Article
Keywords
Animals
Arctic Regions
Body Composition
Body Weight
Dietary Proteins - metabolism
Digestion - physiology
Eating - physiology
Female
Male
Nitrogen - metabolism
Pregnancy
Proteins - metabolism
Reindeer - blood - physiology
Reproduction - physiology
Seasons
Abstract
Reindeer (Rangifer tarandus tarandus) and caribou (Rangifer tarandus granti) use body stores (capital) and food intake (income) for survival and reproduction. Intakes of low-nitrogen (N) food declined in winter and increased in spring (51-83 g dry matter kg(-0.75) d(-1)). Reindeer calved before regaining food intake, whereas caribou calved 28 d later. Body N was conserved by minimizing oxidation of amino acid N to urea. Maternal protein stored from early winter was used for 96% of fetal growth in reindeer but only 84% of fetal growth in later-birthing caribou. Both subspecies rely on maternal body protein for 91% of the protein deposited in the neonate via milk over the first 4 wk. All females lost body protein over winter, but lactating females continued to lose protein while nonreproductive females regained protein. Net costs of lactation above maintenance were greater for N (110%-130%) than for energy (40%-59%). Large fat stores in reindeer spare body protein from oxidation in winter, whereas in caribou, less fat with the same body protein favors migration when food is inadequate. The resilience of Rangifer populations to variable patterns of food supply and metabolic demand may be related to their ability to alter the timing and allocation of body protein to reproduction.
Notes
Erratum In: Physiol Biochem Zool. 2009 Jan-Feb;82(1):104
PubMed ID
18702605 View in PubMed
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Alterations of the pituitary-gonadal axis in the neonatal blue fox (Alopex lagopus) exposed to prenatal handling stress.

https://arctichealth.org/en/permalink/ahliterature52388
Source
Reprod Fertil Dev. 2000;12(3-4):119-26
Publication Type
Article
Date
2000
Author
L V Osadchuka
B O Braastad
I. Huhtaniemi
M. Bakken
Author Affiliation
Institute of Cytology and Genetics, Siberian Department of the Russian Academy of Sciences, Novosibirsk. osadchuk@bionet.nsc.ru
Source
Reprod Fertil Dev. 2000;12(3-4):119-26
Date
2000
Language
English
Publication Type
Article
Keywords
Adrenal Cortex - physiopathology
Animals
Animals, Newborn
Chorionic Gonadotropin - pharmacology
Comparative Study
Estradiol - biosynthesis
Female
Fetus - physiopathology
Foxes - physiology
Hypothalamus - physiopathology
In Vitro
Luteinizing Hormone - metabolism
Male
Organ Size
Ovary - drug effects - pathology - physiopathology
Pituitary Gland - pathology - physiopathology
Pregnancy
Reproduction - physiology
Research Support, Non-U.S. Gov't
Sex Characteristics
Stress - pathology - physiopathology
Testis - drug effects - pathology - physiopathology
Testosterone - biosynthesis
Abstract
Handling is a stressor for blue foxes. The influence of preterm handling (1 min daily) of vixens was investigated in 68, 10-day-old cubs, 34 male and 34 female. Body, gonadal and pituitary weight, ano-genital distance, gonadal testosterone and oestradiol content and in vitro production, and pituitary LH content were measured in all cubs. The gonads were frozen or incubated in vitro with, or without, added hCG (2.5 IU per sample). The gonadal incubates and homogenates were analysed for testosterone and oestradiol by radioimmunoassay and the pituitary homogenates for LH by immunofluorometric assay. The results indicate that neonatal fox gonads actively produce steroids and that there are significant sex differences in basal steroid production and response of the gonads to hCG, and in pituitary LH content. Maternal stress resulted in a significant reduction of morphometric and hormonal measures of the reproductive system in neonatal blue foxes, with more drastic effects in female cubs. Gonadal weights were lower in cubs of both sexes from stressed vixens (65.7+/-4.3 v 50.6+/-1.8 mg for the ovaries and 23.2+/-1.0 v. 17.7+/-1.0 mg for the testes, control v. stressed animals, P
PubMed ID
11302420 View in PubMed
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Ambient temperature effects on photo induced gonadal cycles and hormonal secretion patterns in Great Tits from three different breeding latitudes.

https://arctichealth.org/en/permalink/ahliterature95553
Source
Horm Behav. 2008 Jun;54(1):60-8
Publication Type
Article
Date
Jun-2008
Author
Silverin Bengt
Wingfield John
Stokkan Karl-Arne
Massa Renato
Järvinen Antero
Andersson Nils-Ake
Lambrechts Marcel
Sorace Alberto
Blomqvist Donald
Author Affiliation
Department of Zoology, University of Göteborg, Sweden. bengt.silverin@zool.gu.se
Source
Horm Behav. 2008 Jun;54(1):60-8
Date
Jun-2008
Language
English
Publication Type
Article
Keywords
Animals
Ecosystem
Geography
Gonadal Steroid Hormones - blood - secretion
Gonads - metabolism - physiology
Light
Luteinizing Hormone - blood
Male
Passeriformes - blood - metabolism - physiology
Photoperiod
Reproduction - physiology
Seasons
Temperature
Testis - anatomy & histology
Testosterone - blood
Abstract
The present study determines how populations of Great Tits (Parus major) breeding in southern, mid and northern European latitudes have adjusted their reproductive endocrinology to differences in the ambient temperature during the gonadal cycle. A study based on long-term breeding data, using the Colwell predictability model, showed that the start of the breeding season has a high predictability ( approximately 0.8-0.9) at all latitudes, and that the environmental information factor (I(e)) progressively decreased from mid Italy (I(e)>4) to northern Finland (I(e)
PubMed ID
18402961 View in PubMed
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The amino acids used in reproduction by butterflies: a comparative study of dietary sources using compound-specific stable isotope analysis.

https://arctichealth.org/en/permalink/ahliterature76295
Source
Physiol Biochem Zool. 2005 Sep-Oct;78(5):819-27
Publication Type
Article
Author
Diane M O'Brien
Carol L Boggs
Marilyn L Fogel
Author Affiliation
Institute of Arctic Biology, P.O. Box 757000, University of Alaska, Fairbanks, AK, 99775-7000, USA. ffdo@uaf.edu
Source
Physiol Biochem Zool. 2005 Sep-Oct;78(5):819-27
Language
English
Publication Type
Article
Keywords
Amino Acids - metabolism
Analysis of Variance
Animal Nutrition
Animals
Butterflies - metabolism - physiology
Carbon Isotopes - metabolism
Chromatography, Gas
Comparative Study
Diet
Isotope Labeling - methods
Plants - chemistry
Reproduction - physiology
Research Support, U.S. Gov't, Non-P.H.S.
Species Specificity
Abstract
It is a nutritional challenge for nectar-feeding insects to meet the amino acid requirements of oviposition. Here we investigate whether egg amino acids derive from larval diet or are synthesized from nectar sugar in four species of butterfly: Colias eurytheme, Speyeria mormonia, Euphydryas chalcedona, and Heliconius charitonia. These species exhibit a range of life history and differ in degree of shared phylogeny. We use 13C differences among plants to identify dietary sources of amino acid carbon, and we measure amino acid 13C using compound-specific stable isotope analysis. Egg essential amino acids derived solely from the larval diet, with no evidence for metabolic carbon remodeling. Carbon in nonessential amino acids from eggs derived primarily from nectar sugars, with consistent variation in amino acid turnover. There was no relationship between the nonessential amino acids of eggs and host plants, demonstrating extensive metabolic remodeling. Differences between species in carbon turnover were reflected at the molecular level, particularly by glutamate and aspartate. Essential amino acid 13C varied in a highly consistent pattern among larval host plants, reflecting a common isotopic "fingerprint" associated with plant biosynthesis. These data demonstrate conservative patterns of amino acid metabolism among Lepidoptera and the power of molecular stable isotope analyses for evaluating nutrient metabolism in situ.
PubMed ID
16096984 View in PubMed
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152 records – page 1 of 16.