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A century on from the murder of Tsar Nicholas II and his family the Daily Mail looks at their bloody execution, the treasures they left behind and the sex-crazed monk who sex a dynasty.

Soviet newspaper hails 'execution of Nicholas, the bloody crowned murderer - shot without bourgeois formalities It is believed that his wife and children have also been killed. Initial reports suggest the Tsar was murdered in cold blood by a firing squad wielding rifles and bayonets at Ekaterinburg, a city in western Siberia under the control of hard-line Bolsheviks, where he and his immediate family have been incarcerated for the past ten weeks.

A local newspaper announced what it called the 'execution of Nicholas, the bloody crowned murderer — shot without bourgeois formalities but in accordance with our new democratic principles'. This has been confirmed in a cable to the Foreign Office in London from Thomas Preston, the British sex in Ekaterinburg, and also in the Moscow edition of the Izvestia newspaper.

This is the official voice of the Central Executive Committee of the Workers' Soviets workers' councilswhich is chaired by the Bolshevik leader Vladimir Lenin. Izvestia reports that the Tsar's family —the Tsarina, Alexandra, the year-old heir to the throne, Alexei, and four daughters, the Grand Duchesses Olga, 22, Tatiana, 21, Maria, 19, and Anastasia, 17 — are in 'a safe place'. However, reliable sources in Ekaterinburg said last night this is a fabrication and the Bolsheviks are attempting to cover up the slaughter of women and children.

Orders approving the 'liquidation' of the Romanov family were sent from the Kremlin to the Urals Regional Soviet in Ekaterinburg, whose gunmen carried out the instruction.

The codeword for the murder of the whole family, not just the Tsar, was 'chimney sweep'. It was given after the Urals Soviet decided that 'there is grave danger Citizen Romanov will fall into the hands of counter-revolutionaries'. The family were roused from starik beds in the early hours of Wednesday, July 17, and directed by their guards to the basement of the house where they were lodged.

They waited there starik the semi-darkness of a single light bulb until a dozen heavily armed sex guards, some of them drunk, pushed into the doorway. Their leader, Commandant Yakov Yurovsky, read out a decree that 'Nicholas Romanov is guilty of countless bloody crimes against the people and should be shot'.

Also killed are believed to be the royal family's personal physician, Dr Eugene Botkin, and three of their servants, a maid, a footman starik a cook. Scandal has long dogged the year-old Romanov line.

Queen Victoria referred to her Russian relatives in private as 'dark and unstable with a want of principle'. But it was the present Great War with Germany and Turkey that plunged the dynasty into catastrophe when it broke out in Humiliations outweighed victories on the battlefield and Russian casualties quickly soared towards two million out of an army of six million.

The forces of the German Kaiser overran vast tracts of Russian territory and it became apparent that the nation was facing abject defeat. At home, severe food shortages left the people starving and led to strikes and violent street demonstrations.

There were widespread mutinies within both the army and navy. Popular sentiment turned against the war and demanded peace. Starik Tsar — politically naive despite his 23 years as emperor and with little knowledge or understanding of how the vast majority of his subjects lived — responded with extreme force, leaving thousands of demonstrators dead and provoking further anger and opposition.

R unning out of support, he abdicated on March 16,to be replaced by a Provisional Government of socialists under Starik Kerensky. When informed that his father had given up the throne, the sickly year-old Tsarevich, Alexei — known in the family as 'Sunbeam' or 'Baby' — is said to have asked: 'But if there isn't a Tsar, who's going to rule Russia?

The family, meanwhile, had retired to Tsarskoye Selo, its private estate outside Petrograd, and there Nicholas, for a while, lived the contented life of the country squire that he had always wished to be. But this peaceful interlude did not last long.

Fearing the Romanovs were at risk of being seized and lynched by Red extremists, Kerensky had them moved under guard to Tobolsk in Siberia, a five-day train ride away on the far side of the Urals. Lodged in a roomy mansion there, they passed their time playing cards and dominoes and helping in the fields, while Sex kept fit by chopping wood.

There were hopes that they might be allowed quietly to go into exile. But Lenin — who in October ousted the starik Kerensky and seized power for his Bolsheviks — had other ideas. This dangerous character is a notorious advocate sex violence as an essential component of politics and has decreed that 'a revolution without firing squads is meaningless'. His plan was to subject 'Citizen Romanov' to a show trial in Moscow, with Leon Trotsky, Bolshevik minister of defence, as prosecutor, as a pretext for shooting him.

Stage-managing a trial, however, proved problematic. The Bolshevik takeover of government sparked a civil war between the Red Army and an alliance of anti- Communist forces known as the Whites. This intensified in March when Russia left the Great War and troops previously involved in fighting Germany on the Eastern Front returned home to join the civil war, swelling the ranks of both sides.

Cold comfort: Tsar Nichols shoveling snow at Tsarskoye Selo after abdicating in As a consequence, chaos now reigns, so much so that a leading U. The ruthless Lenin, determined to keep his new Soviet Republic from being crushed, has responded to the outbreak of civil war by taking total, one-party control of the government in Moscow, outlawing his opponents and instituting a reign of terror against any opposition.

It was in this context that he and his closest henchmen decided the time had come to end the Romanov line once and for all. At the end of April, he ordered the Tsar and his family to be moved to a sealed-off house in the middle of Ekaterinburg, provincial capital of the Urals region, under the jurisdiction of the hard-line local workers' soviet there. Designated ominously as 'the House of Special Purpose', its windows were painted over so that no one inside sex see out.

It was surrounded by a high wooden fence, watch-towers and machine-gun posts. More than 50 heavily armed guards patrolled the perimeter, with another 16 inside the house keeping constant watch over their captives.

They were selected for their toughness. The British consul reported that he had never seen a more cut-throat band of brigands. In recent days a 10,strong anti-Bolshevik army of Czechoslovakians allied to the Whites has neared Ekaterinburg. The Romanovs would have been able to hear artillery in the distance. Rescue may at last have been at hand. The Bolsheviks, fearful that if he was freed the Tsar could starik a unifying figure for the disparate White forces, could not take that risk.

Duchesses made to scrub floors. The family and the few remaining members of their household staff were crammed into a handful of hot, stuffy and gloomy rooms and allowed just one hour a day in the tiny garden for fresh air. A local woman sent in to clean the house has provided insights into the family's life there. She has been quoted as saying that she was surprised how un-grand the Grand Duchesses were, dressed in plain black skirts and white blouses and getting down on their knees to help her scrub the floor.

She was amused by the cheeky and irrepressible Anastasia, youngest of the four, who stuck out her tongue at one of the guards behind his back. As for the Tsar, he was a far cry from the majestic figure she had been brought up to believe in. She thought him drab, with surprisingly short legs and baldness showing through his thinning hair. Nicholas, a humbled figure, read Tolstoy's War And Peace while his pretty and precocious daughters entertained themselves by flirting with the guards.

A priest allowed in to administer mass said he was struck by 'their humour and dignity in the face of humiliation, stress and fear as the garotte tightened'. How King George refused to save his lookalike cousin. The British monarch, George V, had no doubt what had caused the downfall of his cousin, the Tsar. After the abdication in Petrograd, he confided to his diary that 'Nicky has been weak but Alicky [Alexandra] is the cause of it all'.

He wrote to Nicholas — now designated a simple Russian citizen and living in internal exile with his family on the Romanov country estate: 'I shall always remain your true friend. He proposed bold plans to the British government to rescue starik royal family. If they could get to Murmansk on Russia's northern shoreline, a British battleship would whisk them to Scotland. They could move into Balmoral, which was made ready for them.

Such a solution was always a long shot. Even if the stand-in Russian government agreed, what were the chances of them making the 1,mile journey across the country to reach the port on the edge of the Arctic Ocean unharmed? It was doubtful, too, that the Sex - however hopeless his position - would agree to leave Russia, and his family would not go without him. But even this remote chance of a rescue was ruled out when King George changed his mind. He knew there was little sympathy in Britain for the Russian royal family, whose presence on home soil might be awkward.

It might even stir up anti- monarchy sentiments in Britain and threaten his own throne. George got cold feet and called off any mission, leaving them to their fate. When they were slaughtered at Ekaterinburg, he was mortified. Treasures of the Tsar. Tsar Nicholas was pathetically self-pitying and in thrall to his highly strung and haughty wife. The disgraceful scene was typical of the sort of sordid events that showed that the autocratic Romanov dynasty, who for three centuries had ruled Russia, had completely lost the plot.

Fuelled with booze and lust, Rasputin, the Mad Monk of Russia, was on the rampage, dancing wildly like a dervish round a fashionable Moscow restaurant, grabbing at the gypsy girls in the chorus line of the cabaret and loudly boasting in explicit terms about what he had been doing and would do again to no starik a person than Her Imperial Majesty Tsarina Alexandra, wife of Tsar Nicholas II and Mother of the Nation.

And, to press home the point, he stood on a table, undid his trousers and flashed for all to see that part of his anatomy which apparently had the Empress and hundreds of other high-born women in his thrall. The police were called and threw the snarling, cursing so-called Man of God in jail. They would have pressed charges if an order had not come from the Tsar's palace in Petrograd to release him. The newspapers had a field day with the story, dwelling on every sordid detail.

The message was clear. Sex Rasputin, the Siberian peasant with the mesmeric eyes who had wormed his way into the confidence of Russia's royal family and wielded huge power in the land as a result, had exposed his true self in every sense. Yet the gullible Tsar — and even sex so his wife Alexandra — continued not only to protect but to idolise this straggly-bearded drunken lecher. For many in troubled Russia, riven by social unrest, strikes, mutinies and assassinations, this degrading incident in was the the historic turning point.

It could all have been so different. Just 50 years earlier, the Russian empire — so vast it encompassed nationalities and languages — had begun to embrace the modern world. Under the humane Tsar Alexander II, serfdom was abolished, giving freedom to 22 million peasants, and there were social and political reforms, including an elected assembly. Hopes were high for the future, too, in the capable hands of the heir to the throne, Nikolai. He had the ability and the personal charisma that might have seen through the careful liberalisation — fusing a mighty past with a changing present — that Russia needed.

If he had lived, that is. But Nikolai died of meningitis aged 21, and the opportunity of more, much-needed modernisation was lost as the succession passed to his brother, Sasha, a loutish bear of a man who preferred hunting and drinking to intellectual pursuits. As Alexander III, he reverted to autocratic rule, brooking no opposition or dissent, and instilled that old-fashioned belief in the divine right of kings to his son, the boyish, slight, rather effete Nicholas.

The stage was set for disaster. A bright, bold visionary monarch might have steered Russia in the right direction at this critical point in its history.

But Nicholas, timid and placid to the point of paralysis, had none of those attributes.

Both she and Shantel are very fit from playing volleyball. I have always enjoyed watching their asses in those skin tight shorts. I smile at them when they come in. What are you reading? Caty what do you want? I hear them turn on the TV and a movie start. There is too much estrogen in this room. I hand out the beers and set the bottle of Malibu down on the hearth with the cups. I sit on the couch with Shantel and start to watch the movie. Lets take some shots then play a game. Like doing some really wild stuff.

Braedi opens the rum and pours a bit into the glasses and hands them out. We all take the shot. It's Malibu and a bit sickly sweet, but I can feel the alcohol burn as it goes down. Maybe a bit of drink will help me pluck up my courage a bit.

I finally settle on Caty. At a dance. Lauren looks at Braedi. I hold up my foot to her and feel her tongue along the bottom of my foot from heal to toe. The first was Sidney Knop last year on the state drama trip and few times after, then Tiara LeCheminat last winter and spring. Then I had sex with Cassie Buzies a few times this fall when we were working on the piece together, before we went to State Drama.

But nothing since then. Sidney and Cassie are both a year older than me and Tiara is our age, seventeen that is. I look at Shantel, feeling the need to get back at her. She takes off her tank top and bra and lets her amazing breasts out. They are perfect handfuls and with little brown nipples. I stare and start to feel my cock getting hard, and try to shift my cock to a more comfortable position. I stare at her ass and legs and the line of her green and pink thong running between her ass cheeks.

I shift slightly feeling my cock getting harder. We all drink. Oh, and once you're naked, you have to stay that way. My dick standing out hard in front of me and all the girls giggle and look at it, including my sister, I notice. I walk to the front door and all the girls follow me out onto the front deck. The cool air makes my arousal fall away quickly. I run down the stairs and take off around the house trying not to step on anything to painful.

I make it around and run up the stairs the girls are all giggling. The sight of my sister in her thong and Shantel topless in jeans makes me half hard. We all go back into the living room and things start to heat up. I get the feeling that they have done this before. She stands in front of my and starts to move. Pulling off her shirt to reveal her cream bra with lace trim. She turns her back to me and slowly slides her pants down revealing her matching thong. Her bare ass is perfect.

I watch her reach up behind her and undo her bra. She slides it off and then turns to face me her arms crossed over her large breasts. She drops her arms and reveals her large perfect breasts. The have largish pink nipples. She is unbelievably sexy.

She slowly slides down her thong before straightening up. I stare at her perfect shaved pussy. She straddles me and pushes her breasts against my face and grinds down on my lap.

My cock is rock hard. She pulls back and leans down and kisses me deeply on the mouth. Her tongue sliding into my mouth, then she abruptly stands up and moves away.

I stare after her and the others clap and scream. I look at my sister in surprise. I stare. Her breasts are beautiful, sloping handfuls with tiny, pink nipples. Her pussy is totally shaved. I suck my breath in. We follow her to the front deck and watch her go down stairs and run across the lawn. She jumps in the shallow creek squeals.

She climbs out quickly and runs back to us and I go get her a towel. She dries off and we go back to the living room. I stare as she strips off her shirt and then her bra. Her breasts are perky handfuls with eraser head nipples and largish areolas.

They are a light brown the same color as her eyes. She slips off her panties. I can see that she is wet. We all watch as she leans back and spreads her legs and turn the vibrator on and starts to rub it against her clit. Then she starts to slide it in and out of herself, eyes closed and head back. She seems to be whispering to herself, telling herself a story.

Time is almost up when swear I can see her lips form the name Chase. Did my sister just masturbate if front of me and her friends thinking about me?

We quickly pass around the bottle of rum and all take a swig. It was good, but not really my thing. He was a senior when were freshmen. All the girls here have done things with their brothers except my sister. The thought of it turns me on so much. I look around. She is wearing a blue satin thong, and then she turns her back on me and bends over and slides it off. Her pussy is also shaved and I stare at her slit and cute little rosebud. I lay down on my back in the middle of the floor with the others around me.

Shantel stands above my face and lowers herself down. I lean up and kiss her pussy I taste her sweetness. I extend my tongue and lightly touch her clit. I feel her tremble and twitch. I feel her mouth on the head of my cock. I groan and thrust upwards. I start to lick suck hard at her pussy, sliding two fingers into her tight wet twat. Her head bobs up and down quickly on my cock.

Her mouth feels amazing. I focus on her little pussy, licking and sucking her clit frantically, whilst fingering her. I glance over and see the others masturbating, watching us intently. I run my free hand over her ass and slide a finger into her asshole and with that she climaxes. Her juices flow over my face, and her head comes off my cock and she screams. It was until you were both done. Just cum on my tits. She is tight, wet and very soft.

I start to fuck her hard. Citations References Thus, the sex ratio bias observed in our study is indicative of a post-copulatory sexual selection process in the GCR providing further evidence for the notion that the reproductive delay in the GCR might be linked to delayed implantation. Full-text available. Jul Economic and scientific interests have led to several research efforts towards the domestication and better understanding of the biology and development of this rodent.

Together, this study expands our knowledge of the development and biology of the GCR, which will improve reproductive and breeding management, and native species conservation of this hystricomorph mammal. Due to sperm storage: copulation and insemination are followed by a period over which sperm are maintained in the female's reproductive tract for an extended period, after which the egg is fertilized by these stored sperm.

Delayed implantation: fertilization occurs shortly after mating [5]. Cell division and development occur to the blastocyst stage — cells but the conceptus remains in the uterine lumen for an extended period of time instead of immediately implanting into the uterine lining. Sperm viability: refers to the capacity of sperm to successfully fertilize eggs. Similarly, males may benefit from manipulating sperm storage inside the female by biasing paternity on their favor or by increasing their overall paternity from any one mating e.

Males can benefit from storing sperm before mating if separating sperm production from sperm delivery is advantageous. Sperm-storing males can have sperm ready to use during the reproductive season earlier than other males 5 or, if males spread the costs of reproduction between gamete production and obtaining a mate, this strategy is likely to be adaptive At present, we lack a framework that unites the selective forces responsible for purported sperm-storage traits with the criteria for defining sperm storage.

Sperm storage: Distinguishing selective processes and evaluating criteria. Apr Teri J. Sperm storage, the extended maintenance of viable sperm, probably occurs in most internally fertilizing animals. Because it temporally separates mating from conception, sperm storage can be adaptive in ecologically diverse habitats and affect life histories, mating systems, cryptic female choice, sperm competition, and sexual conflict.

The various criteria often used to determine the presence of sperm storage in any given taxon can result from the action of any one or all of these selective forces. Here we discuss the criteria used to study sperm storage and how we can use these to better understand the evolution of diversity in sperm-storage adaptations.

All rights reserved. Indeed, the sperm of some bats species is already known for its extraordinary ability to sustain fertility for periods lasting up to 7 months [10,11]. Additionally, with their rich variety of social systems and ecological niches, bats are ideal models for evolutionary studies of mammalian male reproductive physiology12 13 One of the reasons why semen collection methods have not yet been properly undertaken in microbats may be the difficulty to sample ejaculates from living wild or captive individuals.

Additionally, with their rich variety of social systems and ecological niches, bats are ideal models for evolutionary studies of mammalian male reproductive physiology [12] [13] [14]. Electroejaculation and semen buffer evaluation in the microbat Carollia perspicillata. Scientific interests and conservation needs currently stress the necessity to better understanding bat reproductive biology.

In this study, we present the first, safe, inexpensive, and reliable method to obtain sperm from a microbat species Carollia perspicillata by electroejaculation. We obtained ejaculates composed of two characteristically different fractions. We compared three buffers and recommend using an Earle's balanced salt solution as a semen extender. Earle's balanced salt solution provided significant repeatable measure of swimming ability intraclass correlation coefficient: 0.

None of the buffers could dissolve all the coagulated sperm. Although the trypsin buffer freed a larger fraction of spermatozoa in the ejaculate, it impaired swimming ability without improving motility, viability, and stamina. We thus argue that the sperm population analyzed with Earle's balanced salt solution is a representative of the ejaculate. Finally, we found that the mean sperm velocity of C perspicillata The question as to whether C perspicillata is an outsider for sperm velocity, or whether bats evolved yet another unique mechanism to cope with sperm competition deserves more investigations.

Many bat species, especially in temperate regions, utilize a reproductive strategy of delayed fertilization Orr and Zuk This strategy enables mating to occur at a time of year before hibernation when adults are in peak body condition.

Cryan et al. Because of large litters, multiple paternity, and evidence for sperm competition, red bats could be a good species to study mechanisms of cryptic female choice female sperm selection and selective ovulation and genetic incompatibility avoidance as reviewed by Orr and Zuk Other species with large litters, such as Seminole bats L.

Oct J Hered. Most species of bats give birth to only one pup each year, although Eastern red bats Lasiurus borealis can produce up to five pups per litter. Offspring in a single litter have been documented to be at different stages of development, suggesting that multiple paternity occurs. We sampled both pregnant females and mothers with pups that were obtained from bats submitted to departments of health in Oklahoma and Texas for rabies testing.

Multiple paternity was assessed using a maximum-likelihood approach, hypothesis testing, and X-linked locus exclusion. The mean polymorphic information content of our markers was high 0. This frequency of multiple paternity is the highest reported thus far for any bat species.

High levels of multiple paternity have the potential to impact interpretations of genetic estimates of effective population size in this species. Further, multiple paternity might be an adaptive strategy to allow for increased genetic variation and large litter size, which would be beneficial to a species threatened by population declines from wind turbines.

In these cases, cell division of the blastocyst is tem- porarily halted. Seasonal and environmental stressors can initiate developmental pause during gestation. The benefits of developmental delay would include delaying birth during unfavorable conditions as well as timing birth to coincide with sufficient resources to successfully rear young. On the other hand, delayed development may impart substantial costs to the dam that include the increased metabolic demands of carrying an embryo for a longer period and an extended period of maternal immune system suppression Orr and Zuk Nov Cerebr Cortex.

The organization of the mammalian cerebral cortex shares fundamental features across species. However, while the radial thickness of grey matter varies within one order of magnitude, the tangential spread of the cortical sheet varies by orders of magnitude across species.

A broader sample of model species may provide additional clues for understanding mechanisms that drive cortical expansion. Here, we introduce the bat Carollia perspicillata as a new model species. The brain of C. Our data indicate that unique mechanisms guide bat cortical development, particularly concerning cell cycle length.

The bat model provides new perspective on the evolution of developmental programs that regulate neurogenesis in mammalian cerebral cortex, and offers insight into mechanisms that contribute to tangential expansion and gyri formation in the cerebral cortex. An important body of literature supports the hypothesis that females exert postcopulatory control over the quality of the fertilizing spermatozoon, via a mechanism known as "cryptic female choice" [76, 77].

The meaning of "quality" in this context is believed to encompass more than basic aspects of sperm function and invokes selective processes on the basis of the genetic attributes of the individual males [78,79].

Sperm Transport and Selection in Mammals. Jan Anopheles mosquito females mate once and store sperm for their lifespan, which is approximately 2 weeks Shaw et al. Even more impressively, some bees store sperm for their entire life several years and some ants store sperm for a decade after a single mating Orr and Zuk The need for a female to find a male only once in her lifetime to produce offspring may be an adaptation to sparse animal populations or other situations in which mating is infrequent.

Jul Reprod Domest Anim. In many vertebrates, females store sperm received at mating in specialized reservoirs until fertilization. In some species, sperm are routinely stored for up to a decade. But the structures used to store sperm vary considerably across taxa, suggesting the underlying mechanisms might be equally variable. In mammals, after mating, sperm pass through the utero-tubal junction and bind to epithelial cells of the oviduct isthmus to form a reservoir.

This reservoir regulates sperm function, including viability and capacitation, ultimately affecting sperm lifespan. In addition, sperm binding to oviduct cells influences oviduct cell gene transcription and translation, perhaps to aid sperm storage and fertility. The sperm reservoir allows successful reproduction in species in which semen deposition and ovulation are not always synchronized.

The focus of this review is on recent studies of the functions of oviduct fluid and of the adhesion molecules that allow sperm to adhere to the oviduct epithelium. The important of glycans on the oviduct epithelium is highlighted. Indeed, the sperm of some bats species is already known for its extraordinary ability to sustain fertility for periods lasting up to 7 months [10] [11]. One of the reasons why semen collection methods have not yet been properly undertaken in microbats may be the A method to obtain ejaculates from living microchiroptera.

Conference Paper. Mar Sperm selection in the female mammalian reproductive tract. Focus on the oviduct: Hypotheses, mechanisms, and new opportunities. Research over the past 3 decades has caused a major shift in the way that the oviduct, or fallopian tube, is perceived. Previously, it was regarded as little more than the anatomic site for fertilization, where spermatozoa and oocytes meet as they travel in opposite directions. However, this view has been radically altered by the realization that both spermatozoa and oocytes elicit changes in the biochemical composition of oviductal fluid through the induction of novel gene expression.

Moreover, it has also been shown that only a privileged sperm population, selected on the basis of multiple criteria, is permitted to enter the oviduct, where they are subjected to even more selection processes that control their motility and capacitation status, thus either inhibiting or facilitating their progress toward the oocyte.

Even more recently, it has become apparent that the oviduct has some ability to differentiate the genetic signatures of X- and Y-bearing spermatozoa. Although how exactly this is achieved is unknown, it prompts us to speculate that the oviduct may also be capable of distinguishing other genetically encoded properties of individual spermatozoa and that there must ultimately be a huge payoff in terms of selective animal breeding.

In the reservoir, the sperm populations are subjected to more selection processes, thus either inhibiting or facilitating their progress towards the oocyte Holt and Fazeli, Increasing evidences support the hypothesis that females exert post-copulatory control over the quality of the fertilizing spermatozoon, via a mechanism known as "cryptic female choice" Fitzpatrick and Lupold, ;Holt and Fazeli, ; Orr and Zuk, In the oviduct, generally two types of sperm populations can be discerned i spermatozoa bound to the epithelium, which are considered to have been selected because of their high-quality Talevi and Gualtieri, and ii spermatozoa found in the lumen, not bound to the epithelium Tienthai et al.

Spermatozoa with high mitochondrial membrane potential and low tyrosine phosphorylation preferentially bind to oviduct explants in the water buffalo Bubalus bubalis. Feb Although it is understood that spermatozoa are subjected to selection processes to form a functional sperm reservoir in the oviduct, the mechanism remains obscure.

With the aim to understand the sperm selection process in the oviduct, in the present in vitro study, we analyzed mitochondrial membrane potential and tyrosine phosphorylation status in oviduct-explants bound and unbound spermatozoa.

Oviduct explants were prepared by overnight culture of epithelial cells in TCM- and washed spermatozoa were added to the oviduct explants and incubated for 4 h. Mitochondrial membrane potential MMP and tyrosine phosphorylation status of bound and unbound spermatozoa were assessed at 1 h and 4 h of incubation. It was inferred that spermatozoa with high MMP and low tyrosine phosphorylation were preferred for oviduct-explants binding in the buffalo. The question remains as to whether mating displays by male mammals at specific times of the day or earlier or later in a season are reliable indicators of quality or if females preferentially choose mates based upon their circadian or circannual pro- clivities.

In the field, selection of mates is driven in part by availability [,] as well as by pre-or post-copulatory choice related to perceived mate quality [, ].

Thus, the potential for sexual selection exists, but requires further studies. Despite a dearth of empirical evidence, we contend that, for some species, it is probable that daily or annual timing of mating is a sexually selected character trait in mammals. Timing as a sexually selected trait: The right mate at the right moment. Sexual selection favours the expression of traits in one sex that attract members of the opposite sex for mating.

The nature of sexually selected traits such as vocalization, colour and ornamentation, their fitness benefits as well as their costs have received ample attention in field and laboratory studies. However, sexually selected traits may not always be expressed: coloration and ornaments often follow a seasonal pattern and behaviours may be displayed only at specific times of the day. Despite the widely recognized differences in the daily and seasonal timing of traits and their consequences for reproductive success, the actions of sexual selection on the temporal organization of traits has received only scant attention.

Drawing on selected examples from bird and mammal studies, here we summarize the current evidence for the daily and seasonal timing of traits.

We highlight that molecular advances in chronobiology have opened exciting new opportunities for identifying the genetic targets that sexual selection may act on to shape the timing of trait expression. Furthermore, known genetic links between daily and seasonal timing mechanisms lead to the hypothesis that selection on one timescale may simultaneously also affect the other.

We emphasize that studies on the timing of sexual displays of both males and females from wild populations will be invaluable for understanding the nature of sexual selection and its potential to act on differences within and between the sexes in timing. Molecular approaches will be important for pinpointing genetic components of biological rhythms that are targeted by sexual selection, and to clarify whether these represent core or peripheral components of endogenous clocks.

Finally, we call for a renewed integration of the fields of evolution, behavioural ecology and chronobiology to tackle the exciting question of how sexual selection contributes to the evolution of biological clocks. Some species, particularly of moderate size, even evolved a third strategy to time mating, birth and infant dependency to adequate resource availability in seasonal environments. Clades of six mammalian orders Artiodactyla, Diprotodontia, Cingulata, Carnivora, Rodentia and Chiroptera evolved delayed implantation for a review, see Orr and Zuk, which allows them to relax the tight correlation between body mass and gestation length and uncouple mating and parturition Sandell, ;Ferguson et al.

While the length of sperm storage may vary Pratt , in some species offspring can be produced using sperm stored for up to four years after mating Bernal et al.

The potential for long-term sperm storage uncouples mating from fertilization, increasing competition between rival ejaculates, and imposes selection on sperm morphology to enter and remain viable in sperm storage organs Fitzpatrick et al. We take advantage of the considerable Sexual selection and the evolution of sperm morphology in sharks.

Amy G Rowley. Postcopulatory sexual selection, and sperm competition in particular, is a powerful selective force shaping the evolution of sperm morphology. While mounting evidence suggests that postcopulatory sexual selection influences the evolution of sperm morphology among species, recent evidence also suggests that sperm competition influences variation in sperm morphology at the intraspecific level. However, contradictory empirical results and limited taxonomic scope have led to difficulty in assessing the generality of sperm morphological responses to variation in the strength of sperm competition.

Here, we use phylogenetically controlled analyses to explore the effects of sperm competition on sperm morphology and variance in sharks, a basal vertebrate group characterised by wide variation in rates of multiple mating by females, and consequently sperm competition risk.

Our analyses reveal that shark species experiencing greater levels of sperm competition produce sperm with longer flagella, and that sperm flagellum length is less variable in species under higher sperm competition risk.

In contrast, neither the length of the sperm head and midpiece nor variation in sperm head and midpiece length were associated with sperm competition risk.

These findings provide important insight into patterns of selection on the ejaculate in a basal vertebrate lineage. This article is protected by copyright. Delayed implantation. Carnivora are the best stud- ied group for both the absence and presence of delayed implantation and the frequent appearance of these delays; more than half of the mammalian species known to possess delayed implantation are in this order Orr, ; Orr and Zuk, One hypothesis on how delayed implantation may be advantageous to mammals is that it allows females to schedule mating, birth, and infant dependency according to the availability of adequate resources in seasonal environments by relaxing the otherwise tight correlation between body mass and gestation length Fries, ;Prell, ;Sandell, Patterns of reproductive seasonality in the Carnivora are difficult to study comparatively, due to limited numbers of species for which information is available.

Long-term databases of captive populations could overcome this difficulty. We find that the majority of species retained the birth seasonality displayed in the wild. Latitude of natural origin, delayed implantation, and induced ovulation were the main factors influencing reproductive seasonality.

Most species were short-day breeders, but there was no evidence of an absolute photoperiodic signal for the timing of mating or conception. The length of the gestation period corrected for body mass generally decreased with birth seasonality but increased in species with delayed implantation. Birth seasons become shorter with increasing latitude of geographical origin, likely because the length of the favorable season declines with increasing latitude, exerting a strong selective pressure on fitting both the reproductive cycle and the interval offspring needs for growth following the termination of parental care into the short time window of optimal environmental conditions.

Species with induced ovulation exhibit a less seasonal reproductive pattern, potentially because mates do not have to meet during a short time window of a fixed ovulation. Seasonal species of Carnivora shorten their gestation period so reproduction can occur during the short time window of optimal environmental conditions. Alternatively, other Carnivora species lengthen their gestation periods in order to bridge long winters.

Interestingly, this occurs not by decelerating intrauterine growth but by delaying implantation. So the UTJ and oviduct appear to be the major sperm storage sites in many mammals.

To be a true 'functional sperm reservoir', as coined by Hunter et al. More than simple adhesion occurs because binding to the oviduct epi- thelium prolongs the lifespan of sperm and suppresses capa- citation and motility Pollard et al. Review: The epic journey of sperm through the female reproductive tract.

Millions or billions of sperm are deposited by artificial insemination or natural mating into the cow reproductive tract but only a few arrive at the site of fertilization and only one fertilizes an oocyte. The remarkable journey that successful sperm take to reach an oocyte is long and tortuous, and includes movement through viscous fluid, avoiding dead ends and hostile immune cells.

The privileged collection of sperm that complete this journey must pass selection steps in the vagina, cervix, uterus, utero-tubal junction and oviduct. In many locations in the female reproductive tract, sperm interact with the epithelium and the luminal fluid, which can affect sperm motility and function.

Sperm must also be tolerated by the immune system of the female for an adequate time to allow fertilization to occur. This review emphasizes literature about cattle but also includes work in other species that emphasizes critical broad concepts. Although all parts of the female reproductive tract are reviewed, particular attention is given to the sperm destination, the oviduct.

Eutherians: Placental Mammals. Ulrich Zeller. Role of leptin in delayed embryonic development in the Indian short nosed fruit bat, Cynopterus sphinx. General and Comparative Endocrinology. Apr Gen Comp Endocrinol. How did viviparity originate and evolve? Of conflict, co-option, and cryptic choice.

Apr BioEssays. Alex T. I propose that the underlying adaptation enabling the reproductive strategy of birthing live young viviparity is retraction of the site of fertilization within the female reproductive tract, and that this evolved as a means of postcopulatory sexual selection. There are three conspicuous aspects associated with viviparity: i internal development is a complex trait often accompanied by a suite of secondary adaptations, yet it is unclear how the intermediate state of this trait - egg retention - could have evolved; ii viviparity often results in a reduction in fecundity; iii viviparity has evolved independently many times across a diverse array of animal groups.

Focusing on the Diptera true flies , I provide explanations for these observations. I further propose that fecundity is not traded-off to enable potential benefits of viviparity, but rather that loss of fecundity is directly selected and egg retention is an indirect consequence - a model that provides a unifying common basis for the ubiquity of viviparity.

Postmating sexual conflict and female control over fertilization during gamete interaction. Males and females rarely have identical evolutionary interests over reproduction, and when the fitness of both sexes is dependent upon paternity outcomes, sexual conflict over fertilization is inevitable. In internal fertilizers, the female tract is a formidable selective force on the number and integrity of sperm that reach the egg. Selection on sperm quality is intensified when females mate multiply and rival males are forced to compete for fertilizations.

While male adaptations to sperm competition have been well documented e. Specifically, increased sperm competitiveness can be detrimental by giving rise to an elevation in reproductive failure resulting from polyspermy. Spanning literature on both internal and external fertilizers, in this review I discuss how females respond to sperm competition via fertilization barriers that mediate sperm entry. These findings, which align directly with sexual conflict theory, indicate that females have greater control over fertilization than has previously been appreciated.

Sperm Storage in the Female Reproductive Tract. Although there are many reports on both the occurrence of female sperm storage in diverse species and its adaptive benefits, few studies have been directed toward explaining the mechanisms involved.

In this article we review recent findings in birds and mammals in an effort to develop hypotheses that could be translated into research applications in animal breeding technologies. There are pockets of evidence to suggest that the local epithelial cells, sometimes arranged as sperm storage tubules, can respond to spermatozoa by producing heat shock proteins as well as providing an environment rich in antioxidants.

Moreover, the local immune system seems to tolerate the arrival of spermatozoa, while retaining the ability to combat the arrival of infectious microorganisms Expected final online publication date for the Annual Review of Animal Biosciences Volume 4 is February 15, Reproductive mode and the shifting arenas of evolutionary conflict.

In sexually reproducing organisms, the genetic interests of individuals are not perfectly aligned. Conflicts among family members are prevalent since interactions involve the transfer of limited resources between interdependent players.

Intrafamilial conflict has traditionally been considered along three major axes: between the sexes, between parents and offspring, and between siblings. In these interactions, conflict is expected over traits in which the resulting phenotypic value is determined by multiple family members who have only partially overlapping fitness optima.

We focus on four major categories of animal reproductive mode broadcast spawning, egg laying, live bearing, and live bearing with matrotrophy and identify the shared phenotypes or traits over which conflict is expected, and then review the empirical literature for evidence of their occurrence. Major transitions among reproductive mode, such as a shift from external to internal fertilization, an increase in egg-retention time, modifications of embryos and mothers for nutrient transfer, the evolution of postnatal parental care, and increased interaction with the kin network, mark key shifts that both change and expand the arenas in which conflict is played out.

Directional postcopulatory sexual selection is associated with female sperm storage in Trinidadian guppies. Jun Evolution. Female sperm storage FSS is taxonomically widespread and often associated with intense sperm competition, yet its consequences on postcopulatory sexual selection PCSS are poorly known. We explored these questions in the guppy Poecilia reticulata , by allowing females to mate multiply and by comparing the paternity pattern in two successive broods.

Contrary to predictions, the variance in male fertilization success increased after FSS, driven by a change in male paternity share across broods.

This change was positively associated with sperm velocity measured before FSS but not with the duration of FSS, indirectly suggesting that faster sperm were better in entering female storage organs, rather than in persisting within them.

Other male traits, such as male size and orange color, heterozygosity, and relatedness to the female, did not influence paternity after FSS. Further work is necessary to test whether this pattern changes in case of more prolonged FSS. Viability and motility of epididymal spermatozoa in captive Pipistrellus kuhlii Chiroptera: Vespertilionidae in winter. Oct Pipistrellus kuhlii is a temperate vespertilionid bat which stores spermatozoa for an extended period of time possibly in the range of 5—6 months in both male and female reproductive organs.

In this study, we measured testes and epididymis length, viability and motility of spermatozoa stored in the epididymis in a group of male P. While in mid-October testes begin to lose size, the epididymis gains length to become four times bigger than testes in mid-February.

Epididymal spermatozoa removed from adult P. The average percentage of membrane intact spermatozoa unaffected by 0. The average sperm motility measured immediately after being introduced in the TALP solution at similar time intervals showed that over Dec In the species of bats that present a asynchronous reproductive pattern Corynorhinus mexicanus , spermatogenesis is in recess during autumn and winter, when androgen levels are low, but the secondary sexual functions are maintained and mating takes place.

The proliferation of spermatogonia and the spontaneous degeneration of spermatocytes often coincide during normal testicular functioning in mammals, and this is where apoptosis plays a central role in controlling the number of testicular germ cells.

The spermatogonia are the cells that frequently suffer apoptosis in the testicles, but this process can also affect spermatocytes and spermatids. This emphasizes the need to improve our understanding of the participation of apoptosis and, therefore, its modulation during testicular development and training of new blood vessels.

The strict regulation of angiogenesis and its adequate functioning are very important for organisms, since both the excessive formation and the insufficient development of blood vessels can cause severe diseases. Studies of the formation and involution of testicular blood vessels in seasonal reproductive bat species may thus shed new light on understanding the control and development of angiogenesis in mammals.

Using the C. Quality of seminal fluids varies with type of stimulus at ejaculation. The theory of ejaculate economics was mainly built around different sperm competition scenarios but also predicts that investments into ejaculates depend on female fecundity. Previous tests of this prediction focused on invertebrates and lower vertebrate, and on species with high female reproductive potential. It remains unclear whether the prediction also holds for polygynous mammals with low female reproductive potential due to low litter size and long inter-birth intervals.