scholarly journals Pre- and Postcopulatory Traits ofSalvatorMale Lizards in Allopatry and Sympatry

Scientifica ◽  
2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Sergio Naretto ◽  
Cecilia S. Blengini ◽  
Gabriela Cardozo ◽  
Margarita Chiaraviglio
Keyword(s):  
Interspecific Interactions ◽  
Reproductive Traits ◽  
Spatial Gradient ◽  
Lizard Species ◽  
Sympatric Populations ◽  
Before And After ◽  
Mating Opportunities ◽  
Testis Mass ◽  
Sperm Traits ◽  
Secondary Sexual

The reproductive traits of males are under influence of sexual pressures before and after copulation. The strength of sexual selection varies across populations because they undergo varying competition for mating opportunities. Besides intraspecific pressures, individuals seem to be subjected to pressures driven by interspecific interactions in sympatry. Lizards may vary their reproductive strategies through varying sexual characters, body size, gonadal investment, and sperm traits. We evaluated the reproductive traits, involved in pre- and postcopulatory competition, in allopatric and sympatric populations ofSalvatorlizards. We observed a spatial gradient of male competition among populations, with the following order: allopatric zone ofS. rufescens; sympatric zone; and allopatric zone ofS. merianae. Accordingly, variation in secondary sexual character, the relative testis mass, and the length of sperm component was observed between allopatry and sympatry in each species, suggesting differences in the investment of reproductive traits. However, we found that these twoSalvatorspecies did not differ in secondary sexual characters in sympatry. Interestingly, the trade-off between testes and muscle varied differently from allopatry to sympatry between theseSalvatorspecies, suggesting that the influence of social context on reproductive traits investment would affect lizard species differently.

scholarly journals Context-dependent behavioral plasticity compromises disruptive selection on sperm traits in squid

2020 ◽  
Author(s):  
Noritaka Hirohashi ◽  
Noriyosi Sato ◽  
Yoko Iwata ◽  
Satoshi Tomano ◽  
Md Nur E Alam ◽  
...  
Keyword(s):  
Behavioral Plasticity ◽  
Mating Behaviour ◽  
Social Contexts ◽  
Disruptive Selection ◽  
Behavioural Plasticity ◽  
Male Mating ◽  
Reproductive Tactics ◽  
Developmentally Regulated ◽  
Mating Opportunities ◽  
Sperm Traits

Male animals are not given equal mating opportunities under competitive circumstances. Small males often exhibit alternative mating behaviours and produce spermatozoa of higher quality to compensate for their lower chances of winning physical contests against larger competitors [1]. Because the reproductive benefits of these phenotypes depend on social status/agonistic ranks that can change during growth or aging [2], sperm traits should be developed/switched into fitness optima according to their prospects. However, reproductive success largely relies upon social contexts arising instantaneously from intra- and inter-sexual interactions, which deter males from developing extreme traits and instead favour behavioural plasticity. Nevertheless, the extent to which such plasticity influences developmentally regulated alternative sperm traits remains unexplored. Squids of the family Loliginidae are excellent models to investigate this, because they show sophisticated alternative reproductive tactics (ARTs) by which small males, known as “sneakers”, produce longer spermatozoa and perform extra-pair copulation to attach their sperm packages near the female seminal receptacle (SR). In contrast, large “consort” males have shorter spermatozoa and copulate via pair-bonding to insert their sperm packages near the internal female oviduct [3]. In addition, plasticity in male mating behaviour is common in some species while it is either rare or absent in others. Thus, squid ARTs display a broad spectrum of adaptive traits with a complex repertoire in behaviour, morphology and physiology [3].

scholarly journals From One Ejaculate to Another: Transference of Sperm Traits via Seminal Plasma Supplementation in the Ram

Biology ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 33
Author(s):  
Christine Green ◽  
Jessica P. Rickard ◽  
Simon P. de Graaf ◽  
Angela J. Crean
Keyword(s):  
Sperm Motility ◽  
Seminal Plasma ◽  
Perceived Risk ◽  
Positive Relationship ◽  
Assisted Reproductive Technologies ◽  
Sperm Quality ◽  
Reproductive Technologies ◽  
Before And After ◽  
The Difference ◽  
Sperm Traits

Males can adjust sperm motility instantaneously in response to the perceived risk of sperm competition. The speed of this response suggests that sperm motility is regulated by changes in seminal plasma rather than changes in the sperm cells themselves. Hence, here we test whether inter-ejaculate variation in seminal plasma can be used to alter sperm quality prior to use in assisted reproductive technologies. We supplemented fresh ejaculates of Merino rams with seminal plasma collected from previous ‘donor’ ejaculates to test whether changes in sperm kinetics were related to the relative quality of donor to focal ejaculates. We found a positive relationship between the change in sperm traits before and after supplementation, and the difference in sperm traits between the donor and focal ejaculate. Hence, sperm motility can be either increased or decreased through the addition of seminal plasma from a superior or inferior ejaculate, respectively. This positive relationship held true even when seminal plasma was added from a previous ejaculate of the same ram, although the slope of the relationship depended on the identity of both the donor and receiver ram. These findings indicate that seminal plasma plays a key role in the control and regulation of sperm kinetics, and that sperm kinetic traits can be transferred from one ejaculate to another through seminal plasma supplementation.

scholarly journals Male sperm storage impairs sperm quality in the zebrafish

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Silvia Cattelan ◽  
Clelia Gasparini
Keyword(s):  
Sperm Quality ◽  
Fertilization Success ◽  
Sperm Storage ◽  
Sperm Dna Fragmentation ◽  
Storage Duration ◽  
Male Sperm ◽  
Sperm Dna ◽  
Mating Opportunities ◽  
Experimental Protocols ◽  
Sperm Traits

AbstractVariation in sperm traits is widely documented both at inter- and intraspecific level. However, sperm traits vary also between ejaculates of the same male, due for example, to fluctuations in female availability. Variability in the opportunities to mate can indeed have important consequences for sperm traits, as it determines how often sperm are used, and thus the rate at which they are produced and how long they are stored before the mating. While being stored within males’ bodies, sperm are subjected to ageing due to oxidative stress. Sperm storage may significantly impair sperm quality, but evidence linking male sperm storage and variation in sperm traits is still scarce. Here, we tested the effect of the duration of sperm storage on within-male variation in sperm traits in the zebrafish, Danio rerio. We found that without mating opportunities, sperm number increased as storage duration increased, indicating that sperm continue to be produced and accumulate over time within males without being discharged in another way. Long sperm storage (12 days) was associated with an overall impairment in sperm quality, namely sperm motility, sperm longevity, and sperm DNA fragmentation, indicating that sperm aged, and their quality declined during storage. Our results confirm that male sperm storage may generate substantial variation in sperm phenotype, a source of variation which is usually neglected but that should be accounted for in experimental protocols aiming to assay sperm traits or maximise fertilization success.

scholarly journals Fishing pressure impacts the abundance gradient of European lobsters across the borders of a newly established marine protected area

2019 ◽  
Vol 286 (1894) ◽  
pp. 20182455 ◽  
Author(s):  
Portia Joy Nillos Kleiven ◽  
Sigurd Heiberg Espeland ◽  
Esben Moland Olsen ◽  
Rene A. Abesamis ◽  
Even Moland ◽  
...  
Keyword(s):  
Fishery Management ◽  
Marine Protected Area ◽  
Spatial Gradient ◽  
Fishing Pressure ◽  
Catch Per Unit Effort ◽  
Management Tools ◽  
Before And After ◽  
Potential Benefits ◽  
Southern Norway ◽  
Surrounding Areas

Marine protected areas (MPAs) are considered viable fisheries management tools due to their potential benefits of adult spillover and recruitment subsidy to nearby fisheries. However, before–after control–impact studies that explore the biological and fishery effects of MPAs to surrounding fisheries are scarce. We present results from a fine-scale spatial gradient study conducted before and after the implementation of a 5 km 2 lobster MPA in southern Norway. A significant nonlinear response in lobster abundance, estimated as catch-per-unit-effort (CPUE) from experimental fishing, was detected within 2 years of protection. After 4 years, CPUE values inside the MPA had increased by a magnitude of 2.6 compared to before-protection values. CPUE showed a significant nonlinear decline from the centre of the MPA, with a depression immediately outside the border and a plateau in fished areas. Overall fishing pressure almost doubled over the course of the study. The highest increase in fishing pressure (by a magnitude of 3) was recorded within 1 km of the MPA border, providing a plausible cause for the depression in CPUE. Taken together, these results demonstrate the need to regulate fishing pressure in surrounding areas when MPAs are implemented as fishery management tools.

Habitat and nest-site partitioning in splendid and variegated fairy-wrens (Aves : Maluridae)

1999 ◽  
Vol 47 (4) ◽  
pp. 317 ◽  
Author(s):  
Elizabeth Tibbetts ◽  
Stephen Pruett-Jones
Keyword(s):  
Life History ◽  
Habitat Use ◽  
Interspecific Competition ◽  
Similar Pattern ◽  
Foraging Behaviour ◽  
Nest Site ◽  
Interspecific Interactions ◽  
Territory Size ◽  
Sympatric Populations ◽  
Nest Placement

Territory size, interspecific interactions, foraging behaviour, habitat use, and nest placement were examined in sympatric populations of splendid (Malurus splendens melanotus) and variegated (M. lamberti assimilis) fairy-wrens. Although these species have similar patterns of life history and biology, they utilise different microhabitats within overlapping territories. Splendid fairy-wrens spent more time on the ground and in open areas, whereas variegated fairy-wrens generally preferred higher and more protected locations. The two species exhibited a similar pattern of separation with respect to foraging behaviour, as splendid fairy- wrens mainly foraged on the ground whereas variegated fairy-wrens preferred bushes. They also partitioned nesting habitat, with splendid fairy-wrens building nests in areas with a greater density of trees than variegated fairy-wrens. Further, splendid fairy-wrens built nests in larger shrubs and farther from the edge of these bushes than variegated fairy-wrens. We suggest that these differences in habitat use decrease interspecific competition between the two species.

Effect of a control burn on lizards and their structural environment in a eucalypt open-forest

2002 ◽  
Vol 29 (5) ◽  
pp. 447 ◽  
Author(s):  
Sarinda Singh ◽  
Anita K. Smyth ◽  
Simon P. Blomberg
Keyword(s):  
Habitat Preferences ◽  
Ground Cover ◽  
Lizard Species ◽  
Habitat Features ◽  
Low Intensity ◽  
Open Forest ◽  
Structural Environment ◽  
Eastern Australia ◽  
Before And After ◽  
Burnt Areas

The composition of an open-forest lizard assemblage in eastern Australia was examined before and after a low-intensity controlled fire and concurrently compared with that in an adjoining unburnt area. The effect of fire on the available structural environment and the habitat used by two focal species, Carlia vivax and Lygisaurus foliorum, was also examined. Lizard species richness was unaffected by the controlled burn as was the abundance of most species. C. vivax was the only species to display a significant reduction in abundance after fire. While the low-intensity fire resulted in significant changes to the available structural environment, there were no compensatory shifts in the habitat preferences of either C. vivax or L. foliorum. The reduction in abundance of C. vivax was congruent with this species' avoidance of burnt areas. C. vivax displayed a non-random preference for ground cover and litter cover, which were reduced in burnt areas. Changes in the availability of preferred structural habitat features are likely to contribute to changes in the abundance of some lizard species. Therefore, even low-intensity disturbances can have an impact on lizard assemblages if critical habitat features are lost or become limiting.

Secondary sexual characters and sperm traits in coho salmonOncorhynchus kisutch

2009 ◽  
Vol 74 (7) ◽  
pp. 1450-1461 ◽  
Author(s):  
T. E. Pitcher ◽  
S. M. Doucet ◽  
J.-M. J. Beausoleil ◽  
D. Hanley
Keyword(s):  
Secondary Sexual Characters ◽  
Sperm Traits ◽  
Secondary Sexual

scholarly journals Survival, Growth, and Reproduction: Comparison of Marbled Crayfish with Four Prominent Crayfish Invaders

Biology ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 422
Author(s):  
Antonín Kouba ◽  
Boris Lipták ◽  
Jan Kubec ◽  
Martin Bláha ◽  
Lukáš Veselý ◽  
...  
Keyword(s):  
Interspecific Interactions ◽  
Single Species ◽  
Freshwater Crayfish ◽  
Sympatric Populations ◽  
Intraspecific Interactions ◽  
High Fecundity ◽  
Signal Crayfish ◽  
Early Maturation ◽  
Red Swamp Crayfish ◽  
Marbled Crayfish

Biological invasions are increasingly recognized ecological and economic threats to biodiversity and are projected to increase in the future. Introduced freshwater crayfish in particular are protruding invaders, exerting tremendous impacts on native biodiversity and ecosystem functioning, as exemplified by the North American spiny-cheek, signal and red swamp crayfish as well as the Australian common yabby. The marbled crayfish is among the most outstanding freshwater crayfish invaders due to its parthenogenetic reproduction combined with early maturation and high fecundity. As their introduced ranges expand, their sympatric populations become more frequent. The question of which species and under what circumstances will dominate in their introduced communities is of great interest to biodiversity conservation as it can offer valuable insights for understanding and prioritization of management efforts. In order to examine which of the aforementioned species may be more successful as an invader, we conducted a set of independent trials evaluating survival, growth, claw injury, and reproduction using single-species stocks (intraspecific interactions) and mixed stocks (interspecific interactions) of marbled crayfish vs. other crayfish invaders since the onset of exogenous feeding. In both single and mixed stocks, red swamp crayfish and yabby grew faster than marbled crayfish, while marbled crayfish were superior to both spiny-cheek and signal crayfish in terms of growth. With the exception of signal crayfish, the faster-growing species consistently reached a higher survival rate. The faster-growing species tended to negatively impair smaller counterparts by greater claw injury, delayed maturation, and reduced fecundity. Only marbled crayfish laid eggs as early as 14 weeks in this study, which is earlier than previously reported in the literature. Thus, the success of marbled crayfish among invasive crayfish is significantly driven by relatively fast growth as well as an early and frequent reproduction. These results shed light on how interactions between invasive populations can unfold when their expansion ranges overlap in the wild, thereby contributing to the knowledge base on the complex population dynamics between existing and emerging invasive species.

scholarly journals Male age and its association with reproductive traits in captive and wild house sparrows

2019 ◽  
Author(s):  
Antje Girndt ◽  
Glenn Cockburn ◽  
Alfredo Sánchez-Tójar ◽  
Moritz Hertel ◽  
Terry Burke ◽  
...  
Keyword(s):  
Sperm Quality ◽  
Bird Species ◽  
Passer Domesticus ◽  
Reproductive Traits ◽  
House Sparrows ◽  
Reproductive Senescence ◽  
Young Males ◽  
Adaptive Models ◽  
Socially Monogamous ◽  
Sperm Traits

Evolutionary theory predicts that females seek extra-pair fertilisations from high-quality males. In socially monogamous bird species, it is often old males that are most successful in extra-pair fertilisations. Adaptive models of female extra-pair mate choice suggest that old males may produce offspring of higher genetic quality than young males because they have proven their survivability. However, old males are also more likely to show signs of reproductive senescence, such as reduced sperm quality. To better understand why old males account for a disproportionally large number of extra-pair offspring and what the consequences of mating with old males are, we compared several sperm traits of both captive and wild house sparrows, Passer domesticus. Sperm morphological traits and cloacal protuberance volume (a proxy for sperm load) of old and young males did not differ substantially. However, old males delivered almost three times more sperm to the female’s egg than young males. We discuss the possibility of a post-copulatory advantage for old over young males and the consequences for females mated with old males.

Variation in sperm morphometry of the African cyprinid Barbus neumayeri (Neumayer’s barb)

2015 ◽  
Vol 93 (4) ◽  
pp. 259-266 ◽  
Author(s):  
M.L. Martínez ◽  
V. Mullin ◽  
A. Schulte-Hostedde
Keyword(s):  
Swimming Performance ◽  
Gonadosomatic Index ◽  
Reproductive Traits ◽  
Reproductive Capacity ◽  
Head Width ◽  
Gonad Mass ◽  
Wide Range ◽  
Sperm Morphometry ◽  
Left And Right ◽  
Sperm Traits

In this study, we explored variation in sperm morphometry of the African cyprinid Barbus neumayeri Fischer, 1884 (Neumayer’s barb) across seven sites with a wide range in dissolved oxygen, from hypoxic swamps to intermittent normoxic streams to well-oxygenated rivers. We explore whether fish physiological condition (K) or hypoxia can affect the reproductive traits, and whether condition–hypoxia dependence of sperm traits including head length (LH), head width (WH), flagellum length (LF), and hydrodynamic ratio (HR) vary across sampling sites. Significant differences were found in fish total length (P = 0.0212), as well as in K, left and right testis masses, total gonad mass, and gonadosomatic index (P < 0.0001 for all traits). Total gonad mass was lower in hypoxic sites than in well-oxygenated sites. Interestingly, the left and right testes from normoxic environments were double the size of testes from hypoxic environments. Despite little variation in sperm flagellum length, sperm heads were longer in swamps than in streams or rivers, giving the sperm head a more hydrodynamic shape. This variation in HR may be beneficial in the more stagnant waters of the swamp compared with the other environments. Future studies are necessary to understand whether variation in sperm morphology correlates with sperm swimming performance and male reproductive capacity.

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