Male's return rate, rather than territory fidelity and breeding dispersal, explains geographic variation in song sharing in two populations of an oscine passerine (Oreothlypis celata)

Abstract We estimated annual return rate, fidelity, and breeding dispersal in a migratory population of Flammulated Owls (Otus flammeolus) in central Colorado. Return rates, based on capture-recapture histories of 39 males and 52 females from 1981 to 2003, were higher for males (84%) than for females (45%). Annual recapture probability was higher for females, because breeders are easier to capture than nonbreeders and females always attempted to nest, whereas some males were unpaired (did not nest) for up to four years. Territory fidelity was male biased (92%, vs. 56% for females, adjusted for undetected emigration), and mean tenure on territories was more than twice as long for males as for females. Females, but not males, had lower return rates to territories in the year following nesting failure compared with females whose nests were successful. Most males appeared to occupy one territory their entire reproductive lives, countering predictions of habitat-selection models that individuals should move to higher-quality habitats when they become available. We estimated that 74% of pairs retained the same mate in consecutive nesting attempts, but mates that bred together for multiple years had no reproductive advantages over mates that bred together for the first time. In most cases, females dispersed from territories if their mates did not return. When females dispersed, they went to territories where total productivity over the study and lifetime reproductive success of new mates were higher than on original territories, which supports the hypothesis that dispersal by females increases individual fitness. Tasa de Retorno, Fidelidad y Dispersión en una Población Reproductiva de Otus flammeolus

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Density-dependent polyphenism and geographic variation in size among two populations of lubber grasshoppers (Romalea microptera)

Ecological Entomology ◽

10.1111/j.1365-2311.2009.01118.x ◽

2009 ◽

Vol 34 (5) ◽

pp. 644-651 ◽

Cited By ~ 3

Author(s):

JASON E. JANNOT ◽

ALEXANDER E. KO ◽

DUSTIN L. HERRMANN ◽

LAURA SKINNER ◽

EMILY BUTZEN ◽

...

Keyword(s):

Geographic Variation ◽

Density Dependent ◽

Two Populations

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Geographic variation in the morphology of the sand-dwelling lizard Nothobachia ablephara (Squamata: Gymnophthalmidae)

Phyllomedusa Journal of Herpetology ◽

10.11606/issn.2316-9079.v18i2p195-207 ◽

2019 ◽

Vol 18 (2) ◽

pp. 195-207

Author(s):

Carolina Nisa Ramiro ◽

Renato Sousa Recoder ◽

Miguel Trefaut Rodrigues

Keyword(s):

Geographic Variation ◽

Morphological Traits ◽

Geographical Variation ◽

Multivariate Analyses ◽

Molecular Study ◽

Northeastern Brazil ◽

Sexually Dimorphic ◽

Morphometric Variation ◽

The One ◽

Two Populations

Geographic variation in the morphology of the sand-dwelling lizard Nothobachia ablephara (Squamata: Gymnophthalmidae). Nothobachia ablephara is a small microteiid lizard with an elongated body and reduced limbs; it occurs in isolated dune felds in the state of Bahia (Xique-Xique and Alagoado) and small sandy patches in northeastern Brazil. A previous molecular study found a marked mtDNA divergence between populations of N. ablephara from Alagoado and Xique-Xique dunes, suggesting that the two populations diverged from one another between 3 and 4 million years ago. Given this isolation, it is interesting to explore whether morphological traits of the lizards refect the reported genetic divergence of the populations. Scale counts of the sexes and the populations differ signifcantly, but there is considerable overlap of values. Univariate and multivariate analyses revealed signifcant morphometric variation between sexes and populations; however, this is mostly explained by size differences. Females are larger than males in all characters that are sexually dimorphic, and individuals from Xique-Xique are larger than those from Alagoado in all characters that vary geographically. The sample from Alagoado has more sexually dimorphic characters than the one from Xique-Xique. Although N. ablephara displays some geographical variation, the two populations could not be unequivocally distinguished by scale counts and morphometric data.

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Geographic variation in the advertisement call of Crinia signifera (Anura:Myobatrachidae) on Kangaroo Island and across southern south-eastern Australia

Australian Journal of Zoology ◽

10.1071/zo08018 ◽

2008 ◽

Vol 56 (4) ◽

pp. 223 ◽

Cited By ~ 2

Author(s):

Murray J. Littlejohn

Keyword(s):

Geographic Variation ◽

Pulse Number ◽

Advertisement Call ◽

Regional Study ◽

South Eastern ◽

Island Sample ◽

Eastern Australia ◽

Continental Islands ◽

Two Populations ◽

South Eastern Australia

The male advertisement call of anuran amphibians has a major role in mate choice, and regional variation in this attribute can act as an indicator of speciation and a marker for genetic differentiation. As part of a regional study of geographic variation in the male advertisement call of Crinia signifera across south-eastern Australia and adjacent larger continental islands, samples of advertisement calls from two populations on Kangaroo Island and two populations on the adjacent Fleurieu Peninsula were compared. Four call attributes were considered: pulse number, call duration, pulse rate and dominant frequency. Pulse number is considered the most reliable for comparative purposes because it is not influenced by effective temperature or audio recording and analysis. The two island populations (central and eastern, ~24 km apart) differ significantly in pulse number, with contact but no overlap of interquartile ranges. The eastern sample differs markedly from those on the nearby Fleurieu Peninsula – which are both similar to the more distant central island sample. Geographic variation in pulse number in these four samples and 11 others from two recent publications is then interpreted in the light of land bridges and lower temperatures of the late Pleistocene and early Holocene.

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Acoustic geographic variation in two populations of Delphinus delphis

The Journal of the Acoustical Society of America ◽

10.1121/1.420829 ◽

1997 ◽

Vol 102 (5) ◽

pp. 3178-3179

Author(s):

Caitlyn Toropova

Keyword(s):

Geographic Variation ◽

Delphinus Delphis ◽

Two Populations

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Seasonal responses and their geographic variation in Chrysopa downesi: ecophysiological and evolutionary considerations

Canadian Journal of Zoology ◽

10.1139/z81-055 ◽

1981 ◽

Vol 59 (3) ◽

pp. 370-376 ◽

Cited By ~ 7

Author(s):

Maurice J. Tauber ◽

Catherine A. Tauber

Keyword(s):

New York ◽

Geographic Variation ◽

Thermal Thresholds ◽

Preoviposition Period ◽

Geographic Populations ◽

Dark Green ◽

Diapause Incidence ◽

T Values ◽

Two Populations ◽

Seasonal Responses

A comparison of Chrysopa downesi strains from Montana and from New York indicates that they share several characteristics in their seasonal cycles: (1) a short-day – long-day requirement for diapause prevention, (2) dark green adult coloration all year round, (3) relatively high t values (lower thermal thresholds for development), and (4) sensitivity to photoperiod during the nondiapause preoviposition period.Responsiveness to prey differs between the two strains. Prey presence very slightly reduces diapause incidence and greatly shortens the nondiapause preoviposition period in the strain from Montana, whereas prey presence has little or no influence on the strain from the northeastern United States. The strains also differ in their ability to terminate diapause spontaneously; unlike the northeastern strain, a proportion of the northwestern strain ends diapause without an overt, external stimulus.The two populations of C. downesi thus share the two characteristics that are basic to the model of C. downesi's sympatric speciation from an ancestor like C. carnea. In contrast, the differences between the two populations in their responsiveness to prey presence parallels the geographic variation in C. carnea. We propose two alternate pathways (polyphyletic and monophyletic) for the evolution of the seasonal responses of the two geographic populations.

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Geographic Variation in Liver Metal Concentrations of Greater Sage-Grouse

Journal of Fish and Wildlife Management ◽

10.3996/092012-jfwm-083 ◽

2013 ◽

Vol 4 (2) ◽

pp. 298-302 ◽

Cited By ~ 1

Author(s):

Erik J. Blomberg ◽

Peregrine L. Wolff ◽

James S. Sedinger

Keyword(s):

Geographic Variation ◽

Small Body ◽

Selenium Deficiency ◽

Local Variation ◽

Sage Grouse ◽

Tissue Concentrations ◽

Metal Concentrations ◽

Low Selenium ◽

Two Populations ◽

Regional Comparisons

Abstract Populations of greater sage-grouse (Centrocercus urophasianus) have declined throughout the species' range. We evaluated metal concentrations in livers sampled from greater sage-grouse collected from hunters in Eureka County, Nevada, during autumn of 2008 and 2010. We make local comparisons of metal concentrations between two populations of greater sage-grouse in Eureka County, as well as regional comparisons with previously reported values for greater sage-grouse collected in Wyoming and Montana. With one exception, tissue concentrations of lead, arsenic, and mercury were below method detection limits. Mean concentrations of iron, molybdenum, and zinc differed between the two Nevada populations, and magnesium, cadmium, molybdenum, and selenium differed between greater sage-grouse in eastern Nevada, and values reported for Wyoming and Montana. In contrast, we found no evidence for local variation in magnesium, copper, cadmium, or selenium, or for regional variation in iron, zinc, or copper. Of particular interest were low selenium concentrations in our study system relative to Wyoming and Montana. Some individuals in our study returned liver selenium values considered consistent with selenium deficiency in domestic poultry. This research adds to the small body of literature on background contaminant levels in greater sage-grouse, and provides evidence for geographic variation in metal concentrations at local and regional scales.

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