The Endocrinology of a Natural Breeding Population of the White-Crowned Sparrow (Zonotrichia leucophrys pugetensis)

Abstract Theory suggests that males that are larger than their competitors may have increased mating success, due to both greater competitive ability and increased attractiveness to females. We examined how male mating success varies with male size in the tessellated darter Etheostoma olmstedi. Previous work has shown that large males tend to move around and breed in vacant breeding sites, and consequently provide less care for their eggs, while smaller individuals can be allopaternal, caring for the eggs of other males as well as for their own. We studied female egg deposition in a natural breeding population using artificial breeding sites and in the laboratory, where female choice of spawning site was restricted to two breeding sites tended by two males of different sizes. In both the field and the laboratory, nests tended by larger males were more likely to receive new eggs. Additionally, the mean size of males associated with a nest was positively correlated with both the maximum coverage of eggs at the nest and the number of times new eggs were deposited. We discuss how the increased mating success of larger males, despite their decreased parental care, may help explain allopaternal care in this species.

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Change in Historical Range of the Ural Owl in Europe

Belgian Journal of Zoology ◽

10.26496/bjz.2016.37 ◽

2020 ◽

Vol 146 (1) ◽

Author(s):

Quentin Goffette ◽

Marceline Denis ◽

Nadja Pöllath ◽

Wim Van Neer

Keyword(s):

Breeding Population ◽

Medieval Period ◽

Western Palearctic ◽

First Occurrence ◽

Local Breeding ◽

Natural Breeding ◽

The Town ◽

Historical Range ◽

Ural Owl ◽

Rule Out

A carpometacarpus recovered during archaeological excavations in the town of Quaregnon is the westernmost find ever reported in Europe of a Ural Owl (Strix uralensis), and the first occurrence for Belgium. Both the morphology of the skeletal element and its measurements rule out an identification as any of the other Strigiformes from the Western Palearctic. The provenance of this specimen, that dates to the medieval period (10th-12th centuries AD), is discussed. It is hypothesized that the bird was a wild animal, but the available evidence does not unequivocally determine whether it belonged to a local, breeding population that went extinct or if it came from a more distant population. However, a survey of other zooarchaeological finds of Ural Owl in Europe shows that the species occurred farther west in the past, outside the present natural breeding range. This suggests that Ural Owl may have found suitable nesting biotopes in Belgium and northern France during the medieval period.

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ANALYSIS OF ACCUMULATION AND DISTRIBUTION OF LEAD IN THE SYSTEM WATER-BOTTOM SEDIMENTS IN THE BACH DANG ESTUARY (VIETNAM)

VESTNIK OF ASTRAKHAN STATE TECHNICAL UNIVERSITY SERIES FISHING INDUSTRY ◽

10.24143/2073-5529-2017-1-62-66 ◽

2017 ◽

pp. 62-66

Author(s):

Truong Van Tuan ◽

Irina Vladimirovna Volkova

Keyword(s):

Bottom Sediment ◽

Bottom Sediments ◽

Water Samples ◽

Suspended Solids ◽

Natural Habitat ◽

Bottom Layer ◽

Sediment Samples ◽

Natural Breeding ◽

System Water ◽

Water Bottom

Research was held in the estuary of the river Bach Dang (Dongbay community, Rakhtay district, Hai Phong, Vietnam) in June, 2012 - May, 2013. Concentration of lead was studied in water, suspended solids and bottom sediment. Clam beach (natural breeding environment of Meretrix lyrata ) was inspected regularly, every month. Water samples were taken 6 times from the bottom layer 10 cm down the bottom, once per 3 hours in each of 12 investigated zones. Bottom sediment samples were taken at the depth 2 cm. The findings show that lead accumulates mainly in suspended solids (23.3 mg/kg) and in bottom sediment (14.31 mg/kg), in water it is in small quantities (0.003 mg/kg). Analysis of bottom sediment samples taken in different places showed that they have even leadcontent, lead is distributed uniformly, localization of contaminations is not found. The results obtained can be assumed as the basis for investigating lead accumulation and its excretion by clam Meretrix lyrata organisms in the natural habitat.

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Larvae of the blow fly Caiusa testacea (Diptera: Calliphoridae) as egg predators of Polypedates cruciger Blyth, 1852 (Amphibia: Anura: Rhacophoridae)

Journal of Threatened Taxa ◽

10.11609/jott.5740.12.17.17374-17379 ◽

2020 ◽

Vol 12 (17) ◽

pp. 17374-17379

Author(s):

W.G.D. Chathuranga ◽

K. Kariyawasam ◽

Anslem De Silva ◽

W.A.Priyanka P. De Silva

Keyword(s):

Sri Lanka ◽

High Impact ◽

Tree Frog ◽

Blow Fly ◽

Breeding Habitats ◽

The Family ◽

Water Container ◽

The Common ◽

Natural Breeding ◽

The Impact

We investigated the impact of dipteran predators on eggs in foam nests of the Common Hour-glass Tree Frog Polypedates cruciger Blyth, 1852 (Anura: Rhacophoridae) in central Sri Lanka. Foam nests (n=24) of P. cruciger were examined at their natural breeding habitats and infected (n=8) and uninfected spawns (n=16) were identified. Emerging tadpoles were collected in a water container hung under each spawn and the average number of tadpoles (N) hatched from infected spawns (N=0) was compared with that of uninfected spawns (N=354 ± 67). Three severely infected spawns were brought to the laboratory and the fly larvae were reared until they metamorphosed to adults. Morphological and molecular identification of the flies confirmed them as belonging to Caiusa testacea Senior-White, 1923 of the family Calliphoridae. The infected spawns were completely destroyed and an estimated average of 400 P. cruciger eggs per spawn were lost. The results revealed a high impact of Caiusa testacea on egg and embryo mortality of P. cruciger.

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Increasing selection gain and accuracy of harvest prediction models in Jatropha through genome-wide selection

Scientific Reports ◽

10.1038/s41598-021-93022-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Adriano dos Santos ◽

Erina Vitório Rodrigues ◽

Bruno Galvêas Laviola ◽

Larissa Pereira Ribeiro Teodoro ◽

Paulo Eduardo Teodoro ◽

...

Keyword(s):

Prediction Models ◽

Block Design ◽

Phenotypic Selection ◽

Breeding Population ◽

Breeding Cycle ◽

Selection Cycle ◽

Genome Wide ◽

Random Block ◽

Random Block Design ◽

Number Of Individuals

AbstractGenome-wide selection (GWS) has been becoming an essential tool in the genetic breeding of long-life species, as it increases the gain per time unit. This study had a hypothesis that GWS is a tool that can decrease the breeding cycle in Jatropha. Our objective was to compare GWS with phenotypic selection in terms of accuracy and efficiency over three harvests. Models were developed throughout the harvests to evaluate their applicability in predicting genetic values in later harvests. For this purpose, 386 individuals of the breeding population obtained from crossings between 42 parents were evaluated. The population was evaluated in random block design, with six replicates over three harvests. The genetic effects of markers were predicted in the population using 811 SNP's markers with call rate = 95% and minor allele frequency (MAF) > 4%. GWS enables gains of 108 to 346% over the phenotypic selection, with a 50% reduction in the selection cycle. This technique has potential for the Jatropha breeding since it allows the accurate obtaining of GEBV and higher efficiency compared to the phenotypic selection by reducing the time necessary to complete the selection cycle. In order to apply GWS in the first harvests, a large number of individuals in the breeding population are needed. In the case of few individuals in the population, it is recommended to perform a larger number of harvests.

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Genomics and breeding innovations for enhancing genetic gain for climate resilience and nutrition traits

Theoretical and Applied Genetics ◽

10.1007/s00122-021-03847-6 ◽

2021 ◽

Author(s):

Pallavi Sinha ◽

Vikas K. Singh ◽

Abhishek Bohra ◽

Arvind Kumar ◽

Jochen C. Reif ◽

...

Keyword(s):

Statistical Methods ◽

Genetic Gain ◽

Crop Improvement ◽

Breeding Population ◽

Breeding Cycle ◽

Climate Resilience ◽

Heritability Estimation ◽

Improvement Programs ◽

Statistical Designs ◽

Novel Alleles

Abstract Key message Integrating genomics technologies and breeding methods to tweak core parameters of the breeder’s equation could accelerate delivery of climate-resilient and nutrient rich crops for future food security. Abstract Accelerating genetic gain in crop improvement programs with respect to climate resilience and nutrition traits, and the realization of the improved gain in farmers’ fields require integration of several approaches. This article focuses on innovative approaches to address core components of the breeder’s equation. A prerequisite to enhancing genetic variance (σ2g) is the identification or creation of favorable alleles/haplotypes and their deployment for improving key traits. Novel alleles for new and existing target traits need to be accessed and added to the breeding population while maintaining genetic diversity. Selection intensity (i) in the breeding program can be improved by testing a larger population size, enabled by the statistical designs with minimal replications and high-throughput phenotyping. Selection priorities and criteria to select appropriate portion of the population too assume an important role. The most important component of breeder′s equation is heritability (h2). Heritability estimates depend on several factors including the size and the type of population and the statistical methods. The present article starts with a brief discussion on the potential ways to enhance σ2g in the population. We highlight statistical methods and experimental designs that could improve trait heritability estimation. We also offer a perspective on reducing the breeding cycle time (t), which could be achieved through the selection of appropriate parents, optimizing the breeding scheme, rapid fixation of target alleles, and combining speed breeding with breeding programs to optimize trials for release. Finally, we summarize knowledge from multiple disciplines for enhancing genetic gains for climate resilience and nutritional traits.

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