scholarly journals The relationship between sex change and reproductive success in a protandric marine gastropod

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Antonio Brante ◽  
Adriana Quiñones ◽  
Francisco Silva
Keyword(s):  
Reproductive Success ◽  
Sex Change ◽  
Marine Gastropod ◽  
The Relationship

Annual Reproductive Yield in the Cooperative Pygmy Nuthatch (Sitta pygmaea)

The Auk ◽  
1988 ◽  
Vol 105 (1) ◽  
pp. 70-77 ◽  
Author(s):  
William J. Sydeman ◽  
Marcel Güntert ◽  
Russell P. Balda
Keyword(s):  
Reproductive Success ◽  
Cooperative Breeding ◽  
Reproductive Output ◽  
Breeding Birds ◽  
Overwinter Survival ◽  
Northern Arizona ◽  
Floral Diversity ◽  
Indirect Fitness ◽  
The Difference ◽  
The Relationship

Abstract We studied cooperative-breeding Pygmy Nuthatches (Sitta pygmaea) for 4 yr in northern Arizona. Breeding units contained 2-5 birds. Helpers were found at about 30% of all nests. All helpers that later bred on the study area were male. Helpers were mostly yearlings, and offspring or siblings of the birds that they aided, but often aided at least one unrelated breeder. Breeding units with helpers produced significantly more young than those without helpers. Breeding units in habitats with the greatest floral diversity and structural maturity fledged significantly more young than those in other habitats. Habitat did not influence the effect of helpers. Year effects increased the strength of the relationship between helpers and annual reproductive output. Previous breeding experience and pair-bond duration were not related to reproductive success. Total brood loss, although rare, was responsible for the difference in reproductive output among pairs with and without helpers and between habitats. Breeding birds with helpers benefit by an increase in direct fitness. The advantage to the helpers is not clear but may be an increase in indirect fitness associated with aiding relatives. Helpers may benefit directly, however, by sharing roosting cavities on a group territory thereby enhancing overwinter survival.

Male quality and song repertoires in western meadowlarks (Sturnella neglecta)

1993 ◽  
Vol 71 (5) ◽  
pp. 1059-1061 ◽  
Author(s):  
Andrew G. Horn ◽  
Thomas E. Dickinson ◽  
J. Bruce Falls
Keyword(s):  
Reproductive Success ◽  
Wing Length ◽  
Territory Size ◽  
Male Quality ◽  
Repertoire Size ◽  
Song Repertoire ◽  
Signalling System ◽  
The Relationship ◽  
Sturnella Neglecta ◽  
Song Repertoires

The relationship between song repertoire size and measures of male quality and reproductive success was examined in a Manitoba population of western meadowlarks (Sturnella neglecta). Repertoire size correlated positively with the singer's wing length but not with mass or territory size. Males with larger repertoires tended to pair earlier and males with higher pairing success had larger repertoires. Repertoire size correlated positively with fledging success independently of pairing success. As suggested for other species, repertoire size might serve as a signal to females of male quality. We suggest mechanisms by which this signalling system is maintained.

Aggression, superterritories, and reproductive success in tree swallows

1979 ◽  
Vol 57 (10) ◽  
pp. 2072-2078 ◽  
Author(s):  
Reid N. Harris
Keyword(s):  
Reproductive Success ◽  
Reproductive Output ◽  
Future Generations ◽  
Tree Swallows ◽  
Nestling Growth ◽  
Territorial Aggression ◽  
Nest Boxes ◽  
Nestling Period ◽  
The Relationship ◽  
Insular Population

The relationship between territorial aggression and reproductive success was studied on a well-established, insular population of tree swallows. Four treatments of nest boxes that differed in interbox distances were created. Short interbox distances significantly reduced the occupancy of nest boxes both between and within years. Swallows in short interbox distance treatments defended more than one nest box, which was an additional resource not necessary for their successful reproduction. Excluded potential breeders attempted to colonize vacant boxes within another swallow's territory throughout the nestling period, but were usually prevented by the aggression of the resident pair. Aggressive activity had no direct effect on three measures of a swallow's reproductive output: percent young fledged, nestling growth, and fledgling weights. The concept of intraspecific aggressive neglect is questioned. However, by excluding potential breeders from nesting, for whatever reason, breeding tree swallows increased their relative genetic contribution to future generations.

Relationships among changes of serum leptin concentration, leptin mRNA expression in white adipose tissue (WAT), and WAT fat-cell size in female Japanese black bears (Ursus thibetanus japonicus)

2008 ◽  
Vol 86 (9) ◽  
pp. 1042-1049 ◽  
Author(s):  
S. Nakamura ◽  
T. Okano ◽  
H. Shibata ◽  
M. Saito ◽  
T. Komatsu ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
Reproductive Success ◽  
Cell Size ◽  
White Adipose Tissue ◽  
Black Bears ◽  
Fat Cell ◽  
Serum Leptin ◽  
Ursus Thibetanus ◽  
Fat Cell Size ◽  
The Relationship

As a first step to study the relationship between fat accumulation and reproductive success in Japanese black bears ( Ursus thibetanus japonicus Schlegel, 1857) with the focus on leptin, we determined leptin cDNA sequences in the bears. Next, we studied the possibility of white adipose tissue (WAT) as a leptin secretion source by observing the changes of leptin mRNA expression in WAT by semiquantitative real-time reverse transcript – polymerase chain reaction, the index of WAT fat-cell size, and serum leptin concentration in pregnant bears. Then, based on our results, we discussed roles of leptin in those bears. The amino acid sequences of leptin from the bears were highly identical to that of other carnivores. The expression of leptin mRNA in WAT was detected from September to January, with a tendency to increase in late November and January; the relationship between changes in the index of WAT fat-cell size and those in serum leptin concentration was high (r = 0.55, P < 0.01), with an increase in both in mid-November. These results suggested that leptin was mainly secreted from WAT in bears and that serum leptin concentrations might reflect their nutritional condition. Moreover, leptin might serve as an indicator of their fat mass, which would affect their survival during hibernation and their reproductive success.

Haemoproteusinfected birds have increased lifetime reproductive success

Parasitology ◽  
2015 ◽  
Vol 142 (8) ◽  
pp. 1033-1043 ◽  
Author(s):  
M. ZYLBERBERG ◽  
E. P. DERRYBERRY ◽  
C. W. BREUNER ◽  
E. A. MACDOUGALL-SHACKLETON ◽  
J. M. CORNELIUS ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Lifetime Reproductive Success ◽  
Parasitic Infections ◽  
Host Fitness ◽  
Return Rates ◽  
Long Term Study ◽  
In The Wild ◽  
The Impact ◽  
The Relationship

SUMMARYThe impact of haematozoan infection on host fitness has received substantial attention since Hamilton and Zuk posited that parasites are important drivers of sexual selection. However, short-term studies testing the assumption that these parasites consistently reduce host fitness in the wild have produced contradictory results. To address this complex issue, we conducted a long-term study examining the relationship between naturally occurring infection withHaemoproteusandPlasmodium, and lifetime reproductive success and survival of Mountain White-crowned Sparrows. Specifically, we tested the hypothesis that birds infected with haematozoan parasites have reduced survival (as determined by overwinter return rates) and reproductive success. Contrary to expectation, there was no relationship betweenHaemoproteusandPlasmodiuminfection and reproduction or survival in males, nor was there a relationship betweenPlasmodiuminfection and reproduction in females. Interestingly,Haemoproteus-infected females had significantly higher overwinter return rates and these females fledged more than twice as many chicks during their lifetimes as did uninfected females. We discuss the impact of parasitic infections on host fitness in light of these findings and suggest that, in the case of less virulent pathogens, investment in excessive immune defence may decrease lifetime reproduction.

scholarly journals Plasticity in probabilistic reaction norms for maturation in a salmonid fish

2009 ◽  
Vol 5 (5) ◽  
pp. 628-631 ◽  
Author(s):  
Kentaro Morita ◽  
Jun-ichi Tsuboi ◽  
Toru Nagasawa
Keyword(s):  
Genetic Variation ◽  
Body Size ◽  
Reproductive Success ◽  
Reaction Norm ◽  
Reaction Norms ◽  
Transplant Experiment ◽  
Size At Maturity ◽  
Threshold Size ◽  
Precocious Males ◽  
The Relationship

The relationship between body size and the probability of maturing, often referred to as the probabilistic maturation reaction norm (PMRN), has been increasingly used to infer genetic variation in maturation schedule. Despite this trend, few studies have directly evaluated plasticity in the PMRN. A transplant experiment using white-spotted charr demonstrated that the PMRN for precocious males exhibited plasticity. A smaller threshold size at maturity occurred in charr inhabiting narrow streams where more refuges are probably available for small charr, which in turn might enhance the reproductive success of sneaker precocious males. Our findings suggested that plastic effects should clearly be included in investigations of variation in PMRNs.

The relationship between genetic similarity and reproductive success in the branching coralAcropora intermedia

2013 ◽  
Vol 9 (2) ◽  
pp. 181-188 ◽  
Author(s):  
Naoko Isomura ◽  
Yuichiro Baba ◽  
Shunsuke Nagata ◽  
Masanori Nonaka ◽  
Hiromi Hannah Yamamoto
Keyword(s):  
Reproductive Success ◽  
Genetic Similarity ◽  
The Relationship

Influence on the variation in initiation of breeding in Peromyscus maniculatus

1991 ◽  
Vol 69 (3) ◽  
pp. 698-705 ◽  
Author(s):  
Sean T. Sharpe ◽  
J. S. Millar
Keyword(s):  
Reproductive Success ◽  
Peromyscus Maniculatus ◽  
Nest Site ◽  
Subalpine Forest ◽  
Stream Beds ◽  
Timing Of Initiation ◽  
Overwinter Mortality ◽  
Breeding Seasons ◽  
The Relationship ◽  
Forest Habitats

Correlates of the initiation of breeding by female Peromyscus maniculatus borealis (Mearns) were examined to test the hypotheses that asynchronous breeding was related to age, weight, matriline, and nest-site habitat. Life-history data were collected by mark–recapture techniques and by monitoring natal nests over two breeding seasons in 1985 and 1986. Timing of initiation of breeding was related significantly to nest-site habitat and age, but not to matriline or weight. At approximately the same altitude, females nesting in dry rocky stream beds bred first, followed by those in open rock fields, then shrub areas, and last in subalpine forest. Youngest animals bred first in all habitats, although the relationship between age and initiation date was weak. Habitat effects appeared to be primarily related to microclimatic effects. The influence of habitat on the timing of initiation of breeding also had consequences for reproductive success, total reproductive output, and survival. Reproductive success of first litters was greatest for females nesting in rocky stream beds in the spring and least for females nesting in shrub and forest habitats. The apparent advantages of early breeding in rocky stream beds were offset by greater overwinter mortality.

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