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1

Extra-pair paternity in Varied Tits Poecile varius

100%
Ju J., Yin J., Racey P., Zhang L., Li D., Wan D.
Acta Ornithologica
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2014
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tom 49
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nr 1
Extra-pair paternity is of particular interest in socially monogamous species, in which there is a substantial discrepancy between social and genetic mating systems. Varied Tits Poecile varius are socially monogamous passerine birds with a distribution in Japan, Korea, and northeast China. We established paternity in all individuals of 40 broods by microsatellite genotyping. Extra-pair paternity occurred in 16 of the 40 broods (40%) and accounted for about 14.7% (37/251) of offspring, higher than the average value (11%) among socially monogamous birds. The relatedness between social partners did not correlate with the percentage of extra-pair offspring in the brood and there was no difference in heterozygosity between maternal half-siblings. As the first such investigation in this species, this study adds to our understanding of their mating system and will be useful for comparative studies of variations in extra-pair paternity rate.
2
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Multiple paternity in American mink: using males of different color lines allows mating efficiency evaluation

86%
Seremak B., Felska-Blaszczyk L., Dworecka-Borczyk M.
Acta Scientiarum Polonorum. Zootechnica
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2020
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tom 19
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nr 2
3

Genetic relationships within colonies suggest genetic monogamy in the Eurasian beaver (Castor fiber)

86%
Syruckova A., Saveljev A. P., Frosch C., Durka W., Savelyev A. A., Munclinger P.
Acta Theriologica
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2015
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tom 60
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nr 2
Social monogamy, considered rare in mammals, has been described in two species of beaver, the Eurasion beaver (Castor fiber), and the North American beaver (Castor Canadensis). Social monogamy, however, does not necessarily imply genetic monogamy. For example, in group living mammals, females may engage in extra-pair copulations as a result of increased female mate choice opportunities. Recently, following genetic analysis, a wide range of genetic relationships among colony members have been documented in the North American beaver, including extra-pair paternity. Here, we used microsatellite loci to provide parentage estimates from colonies of the Eurasian beaver in the Kirov region, Russia. No evidence for the presence of any extra-pair young was detected. However, in two cases, we found a pair of unrelated males inhabiting a single colony. Our results suggest that while colonies may comprise both related and unrelated individuals, the genetic mating system appears to match that of the previously inferred social monogamy.
4
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Mating system vs. litter size in farm mink (Neovison vison) – effect of multiple paternity

86%
Felska-Blaszczyk L., Seremak B., Lawrow N.
Acta Scientiarum Polonorum. Zootechnica
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2019
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tom 18
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nr 2
5

Are biochemical-genetic variation and mating systems related in large mammals?

86%
Apollonio M., Hartl G. B.
Acta Theriologica. Supplement
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1993
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tom 38
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nr 2
In some families of large mammals (Cervidae, Bovidae, Canidae), we examined relationships between the various mating systems adopted and biochemical-genetic variation measured in terms of the mean proportion of polymorphic loci (P), mean heterozygosity (H) and derived coefficients, such as the ratio Pt:P and FIS. Our hypothesis was that genetic variability decreases as the degree of polygyny of the mating system adopted increases. Most of the data were in accordance with this prediction, but also some ambiguous results could be observed. Methodological and practical difficulties connected with our synoptical approach, such as the lack of comparability among most electrophoretic studies and the general scarcity of quantitative behavioural data are critically discussed.
6

Influence of operational sex ratio and density on the copulatory behaviour and mating system of Brandt's vole Microtus brandti

86%
Zhang J., Zhang Z.
Acta Theriologica
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2003
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tom 48
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nr 3
The pattern of copulatory behaviour of Brandt's vole Microtus brandti (Radde, 1861) is similar to patterns 11 and 12 as described by Dewsbury and Dixson: no lock, single intromission, thrusting after intromission and multiple ejaculations. Under constant density, when the operational sex ratio (OSR, male to female) was skewed to the males, the mating opportunity of males decreased due to mating interference, while the mating input of female remained the same; when the OSR was skewed to the females, male voles tended to increase mating input while females did not. Under the same OSR (1:1), when density increased, the mating opportunity of both sexes dramati­cally decreased due to mating interference between same sex individuals; the thrusting frequency of males increased, probably due to compensation for the decreased mating opportunity. There was a considerable probability of the voles forming monogamous and polygynous mating relationships. Our results did not support the prediction that when OSR is skewed to male, the mating interval of males will shorten. We suggest that the most predominant mating system and mating interference should be taken into account when investigating an OSR effect. Our study suggested that the Brandt's vole is prone predominantly to monogamy and polygyny. However, due to limitation of observation in the laboratory, further work should be combined with studies in the field.
7

Do male roe deer clump together during the rut?

86%
Melis C., Cagnacci F., Lovari S.
Acta Theriologica
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2005
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tom 50
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nr 2
Movement s an d habitat use of 7 male and 7 female roe deerCapreolus capreolus (Linnaeus, 1758) were studied by radioteleme try from March 1999 to February 2001. Annual and bimonthly home ranges of males were small (ca 10 ha, 95% kernel), with large overlap among individuals throughout the year. Exclusive core areas (ca 0.4 ha, 25% kernel) were concentrated in the forest, a limited and sought-after resource in the study area. The difference in overlap between male exclusive core areas and female home ranges in the pre-rut and rut periods suggested that females made excursions to search for territorial males during the rut Our results support the mating strategy hypothesis of territorial behaviour Different space use patterns occurred between the sexes, with females apparently playing an active role in mate choice by visiting males at clumps of core areas in the forest.
8

Facultative promiscuity in a presumably monogamous mouse Apodemus microps

86%
Bryja J., Stopka P.
Acta Theriologica
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2005
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tom 50
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nr 2
Promiscuity and monogamy are two extremes of fitness optimisation. Direct evidence for both extremes is documented in numerous studies where a measure of promiscuity/monogamy is often the number of fathers in individual litters using, for example, fragment analysis of highly polymorphic microsatellite loci. In this study, five known polymorphic microsatellite loci were used to assess biological parentage of 174 embryos of 24 pregnant females from a natural Czech population of pygmy field-miceApodemus microps Kratochvíl et Rosický, 1952. The results revealed that the majority (67%) of litters were fathered by single males. However, there was a trend showing that the number of males successively (but not significantly) increased during the season, thus suggesting that monogamy in the pygmy field mouse is not obligatory but may depend on a population density and habitat type.
9
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Agronomic performance and heterosis of strawberry inbred hybrids obtained by top-cross mating system

72%
Kaczmarska E., Gawronski J.
Acta Scientiarum Polonorum. Hortorum Cultus
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2019
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tom 18
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nr 1
The aim of this study was to develop an inbred lines from octoploid strawberry and to determine their breeding value by estimating the effects of general combining ability (GCA) and mid-parent heterosis. All inbred lines were obtained through selfing using five cultivars. The number of inflorescences, number of flowers per inflorescence, fruit yield, fruit number per plant, average fruit weight, number and weight of leaves as well as number of runners per plant were recorded from 2014 to 2015. The highest breeding value was estimated for maternal forms of ‘Senga Sengana’ 17 for six important traits. The lowest GCA effects were exhibited by inbred lines derived from clone 1387 18. Degree of heterosis for a given trait differed greatly among hybrids. The highest heterosis in terms of a number of inflorescences, fruit yield, number of fruits per plant and leaf weight occurred in the Kent 7-14 × ‘Dukat’ progeny. The results obtained could be used to evaluate the agronomic performance and to make more efficient choices of parents in current strawberry breeding programs
10

Low incidence of polygyny revealed in a long term study of the Sedge Warbler Acrocephalus schoenobaenus in natural wetlands of the S Poland

72%
Zajac T., Solarz W.
Acta Ornithologica
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2004
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tom 39
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nr 1
In 1996-2002, 227 breeding attempts were studied in a colour-ringed Sedge Warbler population. Although 11% of males in this population resumed singing in order to mate with another female after their first females had laid eggs, only two polygynous males (i.e. 0.6%) were recorded. This is a very low value in comparison to other studies (ca. 7% on average). The low level of polygyny is attributable to the low food abundance in a natural floodplain, as the nestlings in this population were fed on predominantly small food items. Both polygynous males were recorded in 2002; this year was unusual, because flooding in early June (around the hatching date) destroyed most of the broods. This could have led to an influx of new females into the study area, a change in the operational sex ratio, and new mating opportunities for males.
11
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Genetic diversity and mating system of Scots pine plus trees

72%
Wasielewska M., Klemm M., Burczyk J.
Dendrobiology
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2005
|
tom 53
57-62
We have investigated genetic diversity and the mating system of Scots pine plus trees from the Tuchola Forests – Poland, using allozymes as genetic markers. The studied plus trees possess high genetic diversity (expected heterozygosity He = 0.427) and low inbreeding (Wright’s index F = –0.028), which is comparable to Scots pine trees observed in other studies in natural populations and seed orchards. The mating system analyses revealed that almost all offspring produced by the plus trees were due to outcrossing (tm = 0.983), with no apparent bi-parental inbreeding. The estimate of correlation of paternity indicated that each of mother trees is pollinated on average by a relatively large number of effective males (Nep = 30.3). The observed genetic diversity and mating system patterns indicate that the seeds produced by the studied plus trees possess high genetic variation needed in reforestation processes.
12

Effect of the age of ganders on reproductive behavior and fertility in a competitive mating structure

72%
Gumulka M., Rozenboim I.
Annals of Animal Science
|
2017
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tom 17
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nr 3
13

Reproductive asynchrony and its potential role in the mating system of the meadow voles

72%
Pugh S. R., Ostfeld R. S., Tamarin R. H.
Acta Theriologica
|
1993
|
tom 38
|
nr 3
Ims (1987a) hypothesized that the spatial distribution pattern of male voles may be influenced by the temporal distribution of females. When females enter estrus synchronously (i.e. are clumped in time) they represent a defendable resource and males should defend a territory containing a cluster of females. When females breed asynchronously, males should not be territorial. In this study we examined the role of female breeding synchrony on the spacing strategies of male meadow voles Microtus pennsylvanicus (Ord, 1815). Maternity was determined by the transfer of a unique combination of radionuclides from mother to offspring. The date of conception (to the nearest week) was determined by the weight at first capture of newly recruited voles. The number of litters conceived per week ranged from zero to four. The null hypothesis that the number of litters conceived per week was distributed randomly could not be rejected in 8 of 9 grid-years (4 years on 3 grids). This finding of breeding asynchrony in a vole species with nonterritorial males is consistent with Ims' hypothesis-.
14
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Genetic evaluation of seeds of highly endangered Pinus uliginosa Neumann from Wegliniec Reserve for ex-situ conservation program

72%
Lewandowski A., Burczyk J., Wachowiak W., Boratynski A., Prus-Glowacki W.
Acta Societatis Botanicorum Poloniae
|
2005
|
tom 74
|
nr 3
Peat-bog pine Pinus uliginosa Neumann has become extinct or rare in many parts of Europe. We have investigated the levels of genetic variation and inbreeding in seeds collected from a highly endangered reserve of this species in Poland, using allozymes as genetic markers. Generally, a high level of genetic variation was observed. The mean expected heterozygosity was 0.376, while average (Na) and effective (Ne) numbers of alleles per locus were 2.45 and 1.67, respectively. Nevertheless, we have detected relatively low levels of outcrossing, and potential biparental inbreeding. The population-wide multilocus outcrossing rate was estimated to be 0.706 (±0.091), while the minimum variance mean of single-locus estimates was distinctly lower (ts=0.611). The estimates of outcrossing calculated for individual trees ranged widely from 0.051 to 1.017, indicating the complexity of outcrossing patterns. The investigated population of P. uliginasa from Węgliniec is small and surrounded by extensive forest stands of P. sylvestris. Our three-year records of phenological observations demonstrated that flowering periods for P. uliginosa and P. sylvestris overlap, allowing for cross-pollination. The possibility of P. uliginosa pollination by P. sylvestris creates a potential danger of genetic erosion of the P. uliginosa gene pool. Nonetheless, based on a species specific cpDNA marker we have found that among 533 seedlings of P. uliginosa there were only six seedlings carrying cpDNA marker specific for P. sylvestris, indicating that such hybridization seems to be rare.
15

Polyterritoriality and the first record of polygyny in the Red-breasted Flycatcher Ficedula parva in primeval forest

58%
Mitrus C., Socko B.
Acta Ornithologica
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2005
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tom 40
|
nr 2
170-172
Territoriality in Red-breasted Flycatchers was studied in the Białowieża Forest of Eastern Poland during five consecutive breeding seasons (2000-2004). In total 99 males were individually marked, and evidence of polyterritoriality was found in 10% of them. The proportion of polyterritorial males varied from 0% (in 2003) to 13.6% (in 2001). The mean distance between the first and second territories was 278 m (± 179.37, n = 10). The rate of polyterritoriality was not related to age class, as older males defended dual territories that were, on average, not more distantly separated than those of younger males. One case of polygyny was recorded. To our knowledge, this is the first evidence for polyteritoriality and polygyny in male Red-breasted Flycatchers.
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