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Courtship in Unisexual Lizards: A Model for Brain Evolution
... Copulation in teiid lizards may involve some behaviours performed by the male, such as biting the female's flank or pelvic region and posture patterns during the intromission phase (Carpenter, 1960;Crews, 1987;Mahrdt, 1976;Ribeiro et al., 2011;Alfonso & Torres, 2012, Sales & Freire, 2021. Mate guarding after copulation seems to be common in teiid lizards, which reduces the opportunity for female to mate with other males. ...
... The male position of A. ameiva during the intromission phase of copulation is similar to other teiid lizards that do not usually follow the arched posture pattern and bites during this phase (Quesnel, 1978;Censky, 1995;Costa et al., 2013). On the other hand, some male teiids from smaller species adopt the arched pattern, biting the female's pelvic region close to her hind limbs, in a ring shape that Crews (1987) called the 'doughnut posture' (Carpenter, 1962;Mahrdt, 1976;Anderson & Vitt, 1990;Ribeiro et al., 2011;Alfonso & Torres, 2012, Sales & Freire, 2021. ...
The courtship and copulation behaviours of the lizard Ameiva ameiva is described from field observations made at various locations in Brazil. In males, the main behaviours observed during one observation of courtship were head bobbing, circling and walking over the females, rubbing his body against the female, mounting, and dismounting. Females generally remain passive throughout courtship. The reproductive behaviour of A. ameiva resembles that of other teiids, however males exhibit some behavioural peculiarities, such as circling the female to restrict her movements, no cloacal rubbing against the ground, and no biting during copulation.
... This mating posture has been reported for other teiids, including A. tobagana and Pholidoscelis plei D m ri and ibron 1 esne 1 Censky 1995). Another major type of mating posture known for teiids is that in which the male bites the female's trunk and acquires an arched (ring-shaped) posture during the ejaculation phase ("doughnut posture" sensu Crews 1987). Such a posture has been reported for Ameivula ocellifera (Spix, 1825) (Sales and Freire 2021), Pholidoscelis auberi (Coctaeu, 1838) (Alfonso and Torres 2012) and species of the genus Aspidoscelis Fitzinger, 1843 (Carpenter 1962, Mahrdt 1976, Crews 1987 itt 1 . ...
... Another major type of mating posture known for teiids is that in which the male bites the female's trunk and acquires an arched (ring-shaped) posture during the ejaculation phase ("doughnut posture" sensu Crews 1987). Such a posture has been reported for Ameivula ocellifera (Spix, 1825) (Sales and Freire 2021), Pholidoscelis auberi (Coctaeu, 1838) (Alfonso and Torres 2012) and species of the genus Aspidoscelis Fitzinger, 1843 (Carpenter 1962, Mahrdt 1976, Crews 1987 itt 1 . e drivers of s c interspecific variation in teiid mating behaviors are poorly understood. ...
... Furthermore,Ribeiro et al. (2011)suggested that this behaviour may also play a role in male–female communication through a combination of signals, including tactile (substrate vibration), auditory (sound produced by displacement of leaves and sand), visual (the male passes over the burrow opening so that the female is able to see him), and chemical (by means of femoral pores) cues. The series of postures performed by the male during copulation seems to be a pattern in whiptail lizards, since they were also observed in another species (e.g.,Crews 1987). The moment when the male inserts a hemipenis into the female's cloaca and transfers his neck-bite hold to the female's pelvic region, assuming a ring-shaped posture ( " doughnut posture " ;Crews 1987), characterizes the ejaculation phase. ...
... The series of postures performed by the male during copulation seems to be a pattern in whiptail lizards, since they were also observed in another species (e.g.,Crews 1987). The moment when the male inserts a hemipenis into the female's cloaca and transfers his neck-bite hold to the female's pelvic region, assuming a ring-shaped posture ( " doughnut posture " ;Crews 1987), characterizes the ejaculation phase. Ejaculation lasted only 48 seconds in A. ocelli fera from the ESEC Seridó, similar to the copulation event recorded byRibeiro et al. (2011)that lasted 65 seconds. ...
This study provides ecological and behavioural data on the reproduction of the whiptail lizard Ameivula ocellifera in the Caatinga biome, northeastern Brazil. Our fieldwork consisted of monthly trips for three consecutive days, from January 2009 through June 2010. Incidental observations of reproductive behaviour were recorded in 2012, during a study on foraging behaviour. We found sexual dimorphism in maximum body size and head dimensions, with higher values in males. Clutch size averaged 2.41 +/- 0.78 (range: 1-4) and was not correlated with female body size. Egg volume averaged 589.26 +/- 77.27 mm(3), egg mass averaged 0.594 +/- 0.126 g, and relative clutch mass averaged 0.156 +/- 0.053. Twelve of the 29 females in reproductive condition contained vitellogenic follicles and oviductal eggs or corpora lutea simultaneously. We registered reproductive females both in the rainy and dry seasons, and the proportion of reproductive females was significantly correlated with monthly rainfall, but not with air temperature. Average testis volume did not differ annually, and there were no significant relationships of testis volume with rainfall and air temperature. We registered a set of behavioural expressions of A. ocellifera related to courtship and mating; cloacal rubbing is among the most evident behavioural expressions involved in courtship, and males accompanying receptive females occurs before and after copulation. We conclude that A. ocellifera has a prolonged reproductive period in the Caatinga, is apparently continuous, but exhibits seasonal variations in reproductive activity. Rainfall unpredictability in the study area may be the major factor for the prolonged reproductive cycle. Most females produce series of clutches of two eggs each. The reproductive behaviour of A. ocellifera is very similar to North American whiptails, most likely reflecting a common phylogenetic origin among this lineage of lizards.
... Lizards demonstrate a wide variety of sociosexual relations and show complexity of space use, comparable to that of birds or mammals Chapple and Keogh, 2006;Kerr and Bull, 2006). The behavior of unisexual Whiptail Lizards (Cnemidophorus spp.) has been studied extensively (Crews and Fitgerald, 1980;Crews et al., 1986;Crews, 1987Crews, , 1998, but nearly nothing is known about spacing patterns of unisexual lizards. Only one study was partly devoted to this topic (Trofimov, 1981). ...
... Lizards demonstrate a wide variety of sociosexual relations and show complexity of space use, comparable to that of birds or mammals Chapple and Keogh, 2006;Kerr and Bull, 2006). The behavior of unisexual Whiptail Lizards (Cnemidophorus spp.) has been studied extensively (Crews and Fitgerald, 1980;Crews et al., 1986;Crews, 1987Crews, , 1998, but nearly nothing is known about spacing patterns of unisexual lizards. Only one study was partly devoted to this topic (Trofimov, 1981). ...
According to kin selection theory, competition among monoclonal animals must be lower than between unrelated individuals. Thus, we propose that home range and core area overlap in parthenogenetic lizards will be broader than female range overlap in similar gonochoristic species. To test this hypothesis, we examined home range locations and space use of parthenogenetic Armenian Rock Lizards (Darevskia armeniaca) and compared them with home range locations and space use of gonochoristic species. We demonstrated that parthenogenetic Rock Lizards have a total range structure typical of insectivorous lizards, consisting of a sally zone, a home range, and one or more core areas. Some core areas contained activity centers, associated strongly with key basking sites and shelters. Provisional residents were found within the same range for 1 or 2 years, whereas wanderers visited study sites for 1 or 2 weeks per season. Settlement structure varied greatly among years. Home ranges, core areas, and even activity centers and basking sites of parthenogenetic females overlapped extensively, unlike in females of nonparthenogenic species. Monoclonal origins and high level of relatedness within unisexual species are possible explanations of the extended range overlap among parthenogenetic females.
... S1-S3 in the ESM). This posture is also performed by males of other teiids (Carpenter 1962;Crews 1987;Anderson and Vitt 1990;Zaldívar-Rae and Drummond 2007;Alfonso and Torres 2012), but there are also species in which males do not adopt this arched posture during the intromission phase (e.g., Quesnel 1978;Censky 1995;Costa et al. 2013). ...
Across animal taxa, females of non-territorial species have potential opportunities to mate with multiple partners; hence, the primary mechanism available for males to ensure paternity is to guard the receptive female after copulation and repel other males. Hypothetically, mate-guarding is costly for males in terms of energy acquisition and increased risk of injury, and beneficial for females in terms of decreased harassment by other males and an increase in available foraging time. Here, we provide a detailed description of mating behavior and test these hypotheses in the Spix's Whiptail (Ameivula ocellifera). Mating behavior is characterized by the following events: (1) a male courts a female in the entrance of her burrow; (2) if courtship is accepted by the female, a consensual copulation occurs; (3) after copulation the male accompanies the female during her daily activity, being aggressive towards other males; (4) when the female returns to the burrow, the companion male remains vigilant at the entrance and repels rival males. Besides the mate-guarding strategy, alternative mating tactics are adopted by some males that do not guard females after courtship and consensual copulation, while others try to copulate opportunistically with a female without prior courtship. Companion males spent more time vigilant, less time actively foraging , and captured less prey when compared to solitary males. Accompanied females captured prey in a similar proportion to solitary females but spent more time vigilant and less time foraging. Companion males won 100% of their interactions with rival males, chasing them away from the females. Accompanied females hence did not suffer harassment from other males when companion males were close. Our results evidence energetic costs of mate-guarding for males but not increased risk of injuries. By accepting mate-guarding, females do not appear to have energetic gains and lose the advantage of cryptic mate choice but can benefit from access to high-quality males and protection from harassment.
... The female response was not correlated to male size, as found in Agelena limbata Thorell [34]. Nevertheless, cryptic female choice is often affected by male behaviour such as courtship before copulation [43] and especially during copulation (i.e. copulatory courtship) [44]. ...
Sperm competition imposes a strong selective pressure on males, leading to the evolution of various physiological, morphological and behavioral traits. Sperm competition can be prevented by blocking or impeding the access to female genitalia by means of a mating plug. We investigated the factors responsible for plug production and function in the promiscuous female-cannibalistic spider Micaria sociabilis (Gnaphosidae).
We performed mating trials using females with and without a plug that consists of an amorphous mass. The mating trials demonstrated that the probability of male plugging increased non-linearly with the duration of copulation. Copulation duration and plug production seem to be controlled by the female. We found that females terminated matings later if males were fast at genital coupling. Whereas incomplete plugs had disappeared on the day following copulation, complete plugs persisted (40%). In matings with females with complete plugs, only a small proportion of males (7%) were able to remove the plug, indicating the high effectiveness of plugging. Moreover, males ceased attempts to copulate with plugged females with higher probability. 3D X-ray microscopy of the female and male genitalia showed that the plug material can extend far into the female genital tract and that the plug material is produced by a massive gland inside the palpal organ of the modified male pedipalps.
Our study demonstrates that the mating plug in M. sociabilis constitutes an effective male strategy to avoid sperm competition that seems to be under female control.
How biologists and other humans understand life has been shaped by our social history and mammalian biology, which inform the questions we ask. Compared with other tetrapods, amphibians and reptiles show amazing diversity in reproductive biology and life history. Herpetology reveals this variation, expanding what we know as possible and enabling us to ask new questions. Queer perspectives, informed by the lives of diverse biologists, influence what we notice, ask, and investigate. Combining human and herpetological diversity, and attending to queer observations, offers great potential for transformative discoveries.
Male courtship behavior is generally thought to function prior to copulation, as an inducement to the female to allow the male to copulate with her; this study indicates however, that male courtship during and following copulation ("copulatory courtship") is common in insects and spiders (81% of 131 species in 102 genera and 49 families, mostly Coleoptera, Hemiptera, Diptera, and Araneioidea). Copulatory courtship is apparently evolutionarily labile, as expected if it is under sexual selection; intrageneric variation occurred in all 17 genera in which more than one species was observed. In 81% of 94 species with copulatory courtship, the male abandoned the female soon after copulation ended; thus, copulatory courtship appears not to function generally to induce acceptance of further copulatory attempts. The most likely explanation for copulatory courtship is that it represents attempts by males to influence cryptic female choice. This suggests that an aspect of sexual selection by female choice not considered by Darwin may be more important than previously appreciated and that the common practice in evolutionary studies of measuring male reproductive success by counting numbers of copulations may sometimes be misleading because of cryptic female choice during and after copulation.
The aim of this review is to consider the potential benefits that females may gain from mating more than once in a single reproductive cycle. The relationship between non-genetic and genetic benefits is briefly explored. We suggest that multiple mating for purely non-genetic benefits is unlikely as it invariably leads to the possibility of genetic benefits as well. We begin by briefly reviewing the main models for genetic benefits to mate choice, and the supporting evidence that choice can increase offspring performance and the sexual attractiveness of sons. We then explain how multiple matin!: can elevate offspring fitness by increasing the number of potential sires that compete, when this occurs in conjunction with mechanisms of paternity biasing that function in copula or post-copulation. We begin by identifying cases where females use precopulatory cues to identify mates prior to remating. In the simplest case, females remate because they identify a superior mate and 'trade up' genetically. The main evidence for this process comes from extra-pair copulation in birds. Second, we note other cases where pre-copulatory cues may be less reliable and females mate with several males to promote post-copulatory mechanisms that bias paternity. Although a distinction is drawn between sperm competition and cryptic female choice, we point out that the genetic benefits to polyandry in terms of producing more viable or sexually attractive offspring do not depend on the exact mechanism that leads to biased paternity. Post-copulatory mechanisms of paternity biasing may: (1) reduce genetic incompatibility between male and female genetic contributions to offspring; (2) increase offspring viability if there is a positive correlation between traits favoured post-copulation and those that improve performance under natural selection; (3) increase the ability of sons to gain paternity when they mate with polyandrous females. A third possibility is that genetic diversity among offspring is directly favoured. This can be due to bet-hedging (due to mate assessment errors or temporal fluctuations in the environment), beneficial interactions between less related siblings of the opportunity to preferentially fertilise eggs with sperm of a specific genotype drawn from a range of stored sperm depending on prevailing environmental conditions. We use case studies from the social insects to provide some concrete examples of the role of genetic diversity among progeny in elevating fitness. We conclude that post-copulatory mechanisms provide a more reliable way of selecting a genetically compatible mate than pre-copulatory mate choice. Some of the best evidence for cryptic female choice by sperm selection is due to selection of more compatible sperm. Two future areas of research seem likely to be profitable. First, more experimental evidence is needed demonstrating that multiple mating increases offspring fitness via genetic gains. Second, the role of multiple mating in promoting assortative fertilization and increasing reproductive isolation between populations may help us to understand sympatric speciation.
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