Cuvier's Gazelle Research Articles

Analysing the pedigree to identify undesirable losses of genetic diversity and to prioritize management decisions in captive breeding: a case study.

When prevention of species extinction is the priority, captive breeding is a key component in conservation programmes, allowing the recording of pedigree information in studbooks. The genealogical information registered in Cuvier's gazelle studbook between 1975 and 2023 was analysed to (a) assess if the implemented mating policy was successful in preserving the genetic background of the founders (1 male:3 females) in the present population, and b) improve future management and breeding decisions. Although the maternal contribution of one founder female was lost and the mean inbreeding of the total live population was high (0.305 ± 0.095), the breeding policy applied produced better results than expected from a population starting from four founders. It was successful in keeping the individual increase in inbreeding low (0.047 ± 0.021), and, notably, the inbreeding tended to decrease during the last three decades of the breeding programme, ensuring the viability of this highly inbred population. Historical dissemination of individuals among the zoos of Europe and North America caused population structuring and genetic differentiation of the live North American population. However, it did not risk the viability of the captive population. The average relatedness coefficients allowed the identification of individuals with underrepresented genotypes, which is relevant to plan future mating guidelines to keep the founders' representation balanced in the next generations. This study highlights the importance of keeping long-term pedigree information to monitor changes in the genetic diversity of captive populations, which is crucial to implement optimal mating decisions and assuring their long-term viability within an ex situ conservation programme.

Insights from the rescue and breeding management of Cuvier's gazelle (Gazella cuvieri) through whole-genome sequencing.

Captive breeding programmes represent the most intensive type of ex situ population management for threatened species. One example is the Cuvier’s gazelle programme that started in 1975 with only four founding individuals, and after more than four decades of management in captivity, a reintroduction effort was undertaken in Tunisia in 2016, to establish a population in an area historically included within its range. Here, we aim to determine the genetic consequences of this reintroduction event by assessing the genetic diversity of the founder stock as well as of their descendants. We present the first whole‐genome sequencing dataset of 30 Cuvier’s gazelles including captive‐bred animals, animals born in Tunisia after a reintroduction and individuals from a genetically unrelated Moroccan population. Our analyses revealed no difference between the founder and the offspring cohorts in genome‐wide heterozygosity and inbreeding levels, and in the amount and length of runs of homozygosity. The captive but unmanaged Moroccan gazelles have the lowest genetic diversity of all genomes analysed. Our findings demonstrate that the Cuvier’s gazelle captive breeding programme can serve as source populations for future reintroductions of this species. We believe that this study can serve as a starting point for global applications of genomics to the conservation plan of this species.

Spatio-temporal pattern of latrine distribution in reintroduced Cuvier's gazelles (Gazella cuvieri): an assessment in a Mediterranean forest reserve.

Knowledge about the factors affecting the number of active latrines (NAL) of reintroduced Cuvier’s gazelles (Gazella cuvieri Ogilby, 1841) is of a crucial step aiming at understanding their distributional dynamics and their habitats preference. Here, we used six random 500-m transects to assess the effect of season, microhabitat, and management variables on the spatio-temporal pattern of latrines in the Tergou forest reserve (TFR). Our results showed that, in this reserve, NAL is mainly governed by the interaction between season and distance to the nearest developed runway, being higher at the farthest distances from the runway in autumn and the closest distances to it in summer and winter. Variation partitioning analysis confirmed this pattern as the interaction between season and distance to the nearest developed runway explains 82% (p = 0.001) of the total variance in NAL. The distance to the nearest fence also contributes, but marginally, in influencing the NAL in this forest enclosure. For the species’ management and conservation, it is recommended to dispose of sandy open ground areas especially in forest reserves to ensure ideal conditions for reintroduced gazelles. The pursuit of monitoring is necessary to understand mechanisms governing the distributional dynamics of Cuvier’s gazelles more deeply. As any enclosure, the TFR would offer a good opportunity for consolidating and improving the knowledge on this vulnerable mammal species in the view of a successful release in the wild.

Seasonal pattern in browsing trees and shrubs by reintroduced Cuvier's gazelles: a study in Morocco with management implications.

Cuvier’s gazelle (Gazella cuvieri) was reintroduced in Tergou reserve (TR) in 2018–2019 to help restore its population at the Moroccan Central Plateau. A study on browsing trees and shrubs was conducted in this reserve to identify (i) the seasonal pattern of this activity and (ii) the most solicited tree and shrub species. Here, we used six random 500-m transects to collect, each month and at each transect, the number of fresh browsing traces of each encountered tree and shrub species. We used principal component analysis (PCA) and linear regression model (LM) to test seasonal variation of the composition of trees and shrubs browsed. Our results showed that, in this reserve, Olea europaea, Quercus ilex, Cistus salviifolius, and Cistus creticus are mostly browsed during winter, whereas Tetraclinis articulata and Ruta angustifolia are mainly used during spring. This information is useful to the managers of the TR not only to consider the importance of the aforementioned trees and shrubs for reintroduced gazelles but also to take the necessary measures so that the forest stand of this reserve is maintained at an appropriate level. Thus, the pursuit of monitoring is necessary to understand the bio-ecology of this semi-captive population more deeply. For this reason, the TR remains a useful and appropriate reference framework offering the opportunity for consolidating and improving the knowledge on this vulnerable mammal species in the view of a future successful release in the wild.

Incidence of Systemic Amyloidosis and Viability in a Captive Population of Cuvier's Gazelles (Gazella cuvieri)

Incidence of Systemic Amyloidosis and Viability in a Captive Population of Cuvier's Gazelles (Gazella cuvieri)

Updated distribution and local abundance of the endangered Cuvier's gazelle (Mammalia, Bovidae) in Algeria

The Maghreb endemic Cuvier's gazelle experienced a dramatic decline during the 20th century, both in distribution and abundance. After the syntheses published in the 1990's, we update the knowledge on the distribution and abundance of this species in Algeria from two independent sources: (1) field surveys, (2) answers to a questionnaire. The comparison of data collected 25 years after the last inventories suggests a slight reduction of the range, Cuvier's gazelles retreating to the optimum habitats along the south-western part of Algeria. Populations in Tiaret and M'sila governorates, which were particularly monitored, showed different ecology and dynamics.

Evaluating methods for surveying the Endangered Cuvier's gazelleGazella cuvieriin arid landscapes

AbstractThe Endangered Cuvier's gazelleGazella cuvieriis an endemic ungulate of north-western Africa. Information on the species has been based primarily on non-systematic surveys, and the corresponding status estimates are of unknown quality. We evaluate the effectiveness and efficiency of two field methods for systematic surveys of populations of Cuvier's gazelle in arid environments: distance sampling (based on sightings) and sampling indirect sign (tracks and scats). The work was carried out in the north-western Sahara Desert, in Morocco, where what is possibly the largest population of Cuvier's gazelle persists. A logistically viable survey was conducted over a total area of c. 20.000 km2in 10 expeditions during 2011–2014. A total of 67 sites were surveyed, with 194 walking surveys (2,169 km in total). Gazelle signs were detected at 50 sites, and gazelles were sighted at 21 sites (61 individuals). We found a relationship between sightings and abundance indices based on indirect sign, which could be useful for population monitoring or ecological studies. Additionally, the data could be used in occupancy modelling. Density estimates based on distance sampling required considerable effort; however, it is possible to survey large areas during relatively short campaigns, and this proved to be the most useful approach to obtain data on the demographic structure of the population.

Coxiella burnetii detected in three species of endangered North African gazelles that recently aborted

Coxiella (C.) burnetii is the etiological agent of the zoonotic disease known a Q fever. This agent can infect multiple hosts although its pathogenic potential in wild ruminants has been poorly studied. The polymerase chain reaction and the serological test detected the presence of C. burnetii in a population of North African gazelles (n = 355), comprising dorcas gazelle (Gazella dorcas neglecta), dama gazelle (Nanger dama mhorr) and Cuvier's gazelle (Gazella cuvieri) which, some of them, they recently aborted. Serological tests for Brucella spp., C. burnetii, Chlamydophila abortus, border disease pestivirus, and Toxoplasma spp. were performed together with specific cultures to detect Salmonella spp., Listeria spp., and Campylobacter spp. and a polymerase chain reaction for C. burnetii on serum and vaginal swabs samples collected from a representative number of animals (n = 65). These tests only detected the presence of C. burnetii in 18 specimens (27.3%). C. burnetii was the only pathogen detected, with eight animals testing positive on the polymerase chain reaction, 15 on the serological test, and five on both the tests. This article reveals the presence of C. burnetii during a medium and late-stage abortions occurred in a population of North African gazelles. The presence of C. burnetii as causal agent of abortions in Cuvier's gazelles has never been reported. The consequences of the findings are discussed here, showing the need to adopt urgent control measures to prevent the spread of C. burnetii in captive populations that are essential for the conservation of these endangered species.

Better Fitness in Captive Cuvier's Gazelle despite Inbreeding Increase: Evidence of Purging?

Captive breeding of endangered species often aims at preserving genetic diversity and to avoid the harmful effects of inbreeding. However, deleterious alleles causing inbreeding depression can be purged when inbreeding persists over several generations. Despite its great importance both for evolutionary biology and for captive breeding programmes, few studies have addressed whether and to which extent purging may occur. Here we undertake a longitudinal study with the largest captive population of Cuvier's gazelle managed under a European Endangered Species Programme since 1975. Previous results in this population have shown that highly inbred mothers tend to produce more daughters, and this fact was used in 2006 to reach a more appropriate sex-ratio in this polygynous species by changing the pairing strategy (i.e., pairing some inbred females instead of keeping them as surplus individuals in the population). Here, by using studbook data we explore whether purging has occurred in the population by investigating whether after the change in pairing strategy a) inbreeding and homozygosity increased at the population level, b) fitness (survival) increased, and c) the relationship between inbreeding and juvenile survival, was positive. Consistent with the existence of purging, we found an increase in inbreeding coefficients, homozygosity and juvenile survival. In addition, we showed that in the course of the breeding programme the relationship between inbreeding and juvenile survival was not uniform but rather changed over time: it was negative in the early years, flat in the middle years and positive after the change in pairing strategy. We highlight that by allowing inbred individuals to mate in captive stocks we may favour sex-ratio bias towards females, a desirable managing strategy to reduce the surplus of males that force most zoos to use ethical culling and euthanizing management tools. We discuss these possibilities but also acknowledge that many other effects should be considered before implementing inbreeding and purging as elements in management decisions.

Estimates of direct and indirect effects for early juvenile survival in captive populations maintained for conservation purposes: the case of Cuvier's gazelle.

Together with the avoidance of any negative impact of inbreeding, preservation of genetic variability for life-history traits that could undergo future selective pressure is a major issue in endangered species management programmes. However, most of these programmes ignore that, apart from the direct action of genes on such traits, parents, as contributors of offspring environment, can influence offspring performance through indirect parental effects (when parental genotype and phenotype exerts environmental influences on offspring phenotype independently of additive genetic effects). Using quantitative genetic models, we estimated the additive genetic variance for juvenile survival in a population of the endangered Cuvier's gazelle kept in captivity since 1975. The dataset analyzed included performance recording for 700 calves and a total pedigree of 740 individuals. Results indicated that in this population juvenile survival harbors significant additive genetic variance. The estimates of heritability obtained were in general moderate (0.115–0.457) and not affected by the inclusion of inbreeding in the models. Maternal genetic contribution to juvenile survival seems to be of major importance in this gazelle's population as well. Indirect genetic and indirect environmental effects assigned to mothers (i.e., maternal genetic and maternal permanent environmental effects) roughly explain a quarter of the total variance estimated for the trait analyzed. These findings have major evolutionary consequences for the species as show that offspring phenotypes can evolve strictly through changes in the environment provided by mothers. They are also relevant for the captive breeding programme of the species. To take into account, the contribution that mothers have on offspring phenotype through indirect genetic effects when designing pairing strategies might serve to identify those females with better ability to recruit, and, additionally, to predict reliable responses to selection in the captive population.

Germ cell survival and differentiation after xenotransplantation of testis tissue from three endangered species: Iberian lynx (Lynx pardinus), Cuvier's gazelle (Gazella cuvieri) and Mohor gazelle (G. dama mhorr)

The use of assisted reproductive techniques for endangered species is a major goal for conservation. One of these techniques, testis tissue xenografting, allows for the development of spermatozoa from animals that die before reaching sexual maturity. To assess the potential use of this technique with endangered species, testis tissue from six Iberian lynxes (one fetus, two perinatal cubs, two 6-month-old and one 2-year-old lynx), two Cuvier's gazelle fetuses and one 8-month-old Mohor gazelle were transplanted ectopically into nude mice. Tissue from the lynx fetus, perinatal cubs and 2-year-old donors degenerated, whereas spermatogonia were present in 15% of seminiferous tubules more than 70 weeks after grafting in transplanted testis tissue from 6-month-old donors. Seminal vesicle weights (indicative of testosterone production) increased over time in mice transplanted with tissue from 6-month-old lynxes. Progression of spermatogenesis was observed in xenografts from gazelles and was donor age dependent. Tissue from Cuvier's gazelle fetuses contained spermatocytes 40 weeks after grafting. Finally, round spermatids were found 28 weeks after transplantation in grafts from the 8-month-old Mohor gazelle. This is the first time that xenotransplantation of testicular tissue has been performed with an endangered felid and the first successful xenotransplantation in an endangered species. Our results open important options for the preservation of biological diversity.

Parity, but not inbreeding, affects juvenile mortality in two captive endangered gazelles

AbstractGrowing deterministic and stochastic threats to many wild populations of large vertebrates have focused attention on the significance of captive breeding for conservation. Nanger dama mhorr and Gazella cuvieri, two Sahelo‐Saharan species, have declined dramatically since the 1950s, apparently due to excessive hunting and habitat degradation. Today, the earlier is extinct in the wild and the latter survives only in small numbers in a few isolated parts of their range, and captive breeding programmes currently provide an important tool for rearing sustained populations. In natural and captive populations, the largest percentage of mortality is among juveniles. This is most relevant, from an evolutionary perspective, as it has a profound influence on population dynamics and demography, and is pivotal to the conservation and management of captive endangered populations. This study explored the juvenile mortality curve during the first 6 months of life of the species mentioned earlier in captivity. Then, we looked at the causes of this mortality by examining potential mother‐dependent as well as offspring‐dependent sources of juvenile mortality. The resulting curves show that the critical period of mortality is the first 14 days of life. We also found that parity and longevity of the mother affected juvenile mortality in Mohor gazelles. Calves born to primiparous as well as those born to short‐lived mothers were more prone to die than those born to either multiparous or long‐lived mothers. In Cuvier's gazelles, juvenile mortality was explained by the interaction between parity and mother's age and litter composition. Neither mother nor offspring inbreeding had any effect on juvenile mortality in either population. Precise knowledge of the biological factors affecting juvenile mortality is increasingly important for the conservation of large mammals, whether they are captive, managed, reintroduced or simply fragmented, as the neonates are the population's potential recruits.

Play behaviour in goitered gazelle, Gazella subgutturosa (Artiodactyla: Bovidae) in Kazakhstan

In this paper, play behaviour of goitered gazelles is considered for the first time. Young gazelles demonstrated play activity most often, followed by adult males and sub-adults, then adult females. Locomotor play (running, jumping) was the most frequently observed play behaviour, while social play (fighting, sexual play) was noted considerably less often and mostly with males. Adult gazelles played mainly in May and gazelle young in June, and primarily in the evenings (19:00-20:00). Most acts of play lasted from several seconds to a half-minute. Young gazelles played often during their suckling period or, at least in the presence of their mothers. Adult females frequently became involved in their young's play, while males played during grazing or butting. In describing goitered gazelle play patterns, we tested five hypotheses: practice-exercise, surplus energy, locomotor play ontogeny, different play types for specific stages of aging, and the social function of play. Our data for playful behaviour of goitered gazelles supported four of the five hypotheses, but contradicted the fourth listed above, which states, at least for Cuvier's gazelles, that locomotor play appears and disappears earlier than social play. The cause of this difference in results may lie in the different conditions under which groups were observed or the different extent of the studies.

No inbreeding effects on body size in two captive endangered gazelles

Selection for body size is intricate, involving trade-offs between energy costs, reproductive output, foraging efficiency, and interaction with other community members. In dimorphic, polygynous ungulates, body size is highly correlated with reproductive success in both sexes. Body size has been proposed as a potential phenotypic indicator of genetic change, in wild and in captive populations. We analysed the relationship between adult body size and inbreeding in two captive populations of endangered gazelles. Two estimates of inbreeding were used: individual inbreeding coefficient ( F i ) and individual increase in inbreeding (Δ F i ). Six cranial traits and eight post-cranial bones were measured in 87 Cuvier's gazelles and 97 Mohor gazelles. The average level of individual inbreeding found for the alive population of Cuvier's gazelle was 0.236 and for Mohor gazelle 0.260. Our study demonstrated that within our populations most variability in body size is explained by sex, but we have not found any evidence of inbreeding depression in this morphological trait. Our results are surprising in the light of a widely held belief that from an evolutionary point of view close inbreeding has deleterious effects. The great diversity of factors acting on the effects of inbreeding on trait values make difficult to provide a simple framework to understand them all, hence, we suggest fitness consequences of inbreeding has to be assessed considering the conditions under which one should expect inbreeding depression.

Mother traits and offspring sex in two threatened gazelle species in captivity

Since threatened species are generally incapable of surviving in their natural environments, ex situ conservation programs are required to preserve them from total extinction. Captive breeding provides the tool to rear sustained populations. Knowledge about biology of such species is critical for managing such breeding programmes. In this paper, we look at the sex variation in calves surviving to 30 days in captive populations of two endangered polygynous gazelles, Gazella cuvieri and Gazella dama mhorr. We examined which of the following mother traits may affect sex allocation: her age; experience; and inbreeding coefficient. Because twins are quite common in Cuvier's gazelle, we also analyse whether offspring sex is mediated by litter size in this gazelle. In both species the overall sex ratio did not differ from unity at the age of 30 days. These results support the suggestion that for a given population to be in equilibrium, a 1:1 calf sex ratio is to be expected, with females in good condition producing sons and females in poor condition producing daughters. We also found that offspring sex is not significantly related to the same mother traits in the two gazelles studied. Cuvier's gazelle findings showed that only maternal inbreeding influenced offspring sex, the less inbred the mother the higher the probability of producing sons. In contrast, none of the maternal traits studied were related to offspring sex in Mohor gazelle. Two nonexclusive explanations are given to justify differences observed between these two species; one relates to a probable differential cost of producing either sex; the other refers to the actual homozygosis level in captive populations of each species. For Cuvier's gazelle litter size has no effect on offspring sex when the sex of the littermate is taken into account. This result fits predictions derived from Trivers–Willard model: mother in good conditions (less inbred) produce the sex with higher fitness returns (i.e., male), no matter if born at single or twins brood. Many variables are likely to affect progeny sex ratio. We have presently examined only a few. But our results might be of interest in management decisions and conservation programs such as reintroductions.

Effect of egg yolk, cryoprotectant, and various sugars on semen cryopreservation in endangered Cuvier's gazelle ( Gazella cuvieri)

Cryopreservation of spermatozoa from endangered species is a valuable tool for genetic management. Previous studies showed the feasibility of cryopreservation of spermatozoa from various endangered gazelles but have also revealed difficulties with available protocols for semen freezing in Cuvier's gazelle ( Gazella cuvieri). Experiments were carried out to investigate the effect of (a) 5% or 20% egg yolk or 4% or 6% glycerol, and (b) addition of sugars (glucose, fructose, lactose and raffinose) on cryopreservation using a Tes-Tris-based diluent (TEST). A diluent containing 13.5% raffinose, 5% or 20% egg yolk, and 6% glycerol (REYG) was also evaluated. Semen was obtained by electroejaculation from 22 G. cuvieri males. Diluted samples were loaded into 0.25 ml straws, cooled to 5 °C over 1.5 h (−0.16 °C/min), equilibrated at that temperature for 2 h, frozen in nitrogen vapours for 10 min and plunged into liquid nitrogen. Subsamples were assessed for motility and acrosome integrity upon collection, after refrigeration–equilibration, after freezing and thawing, and 2 h after thawing. Use of TEST with 20% egg yolk or with 4% glycerol led to worse motility preservation, whereas TEST with 5% egg yolk and 6% glycerol led to better results. Addition of fructose, lactose or raffinose to TEST resulted in similar or worse preservation of motility than inclusion of glucose. On the other hand, use of a raffinose-based medium with 20% egg yolk and 6% glycerol (REYG) afforded better preservation of motility than use of TEST. With REYG, 20% egg yolk was better than 5% egg yolk for motility preservation. Differences were noted between males in their responses to cryopreservation when using different egg yolk or glycerol concentrations. Moreover, spermatozoa from most males exhibited better cryopreservation with REYG although some were better cryopreserved in TEST. The raffinose-based diluent thus represents an improvement over previous results but more work is needed to better characterize cryopreservation conditions for future routine banking of Cuvier's gazelle spermatozoa.

Inbreeding and Reproduction in Endangered Ungulates: Preservation of Genetic Variation through the Organization of Genetic Resource Banks

There is a constant increase in the number of species suffering marked reductions in population size. This reduction in size and the lack of genetic flow may lead to a decrease in genetic variability and to matings between close relatives (i.e. inbreeding) with an ensuing reduction in fitness. It is thus important to understand the mechanism underlying the deleterious effects of inbreeding and to develop reproductive biotechnologies that will allow the reduction of inbreeding depression by facilitating gene exchange between populations. The study of three endangered species of gazelles, Cuvier's gazelle (Gazella cuvieri), Mohor gazelle (Gazella dama mhorr) and dorcas gazelle (Gazella dorcas neglecta) has revealed that inbreeding negatively affects several semen parameters (motility, sperm morphology, acrosome integrity). Semen cryopreservation has been achieved in the three species but success varies depending on the diluent employed and the level of inbreeding. Artificial insemination of Mohor gazelles have led to the birth of the first gazelle born using frozen-thawed semen but improvements are needed before this technology can be applied on a routine basis for the genetic management of the populations. Collection of oocytes after ovarian stimulation, followed by in vitro maturation, fertilization and culture has met with some initial success in the Mohor gazelle. These, together with other reproductive technologies, will offer an invaluable help in preserving the maximum of genetic diversity of these and related endangered ungulate species.

OUTPUT OF GASTROINTESTINAL NEMATODE EGGS IN THE FECES OF CAPTIVE GAZELLES (GAZELLA DAMA MHORR, GAZELLA CUVIERI AND GAZELLA DORCAS NEGLECTA) IN A SEMIARID REGION OF SOUTHEASTERN SPAIN

Feces from 62 captive African gazelles, including Mhorr gazelles (Gazella dama mhorr), Cuvier's gazelles (Gazella cuvieri), and Dorcas gazelles (Gazella dorcas neglecta), were examined over the course of a year to quantitate nematode egg excretion patterns. Strongyloides sp. eggs appeared only in G. dama during the rainy season. Trichostrongylidae egg excretion showed a marked seasonal variation, with very low levels during the dry and hot period, a finding that is probably attributable to hypobiosis of the predominant species (Camelostrongylus mentulatus). Eggs of the Nematodirus sp., predominantly Nematodirus spathiger, were excreted throughout the year. No seasonal pattern was observed in Trichuris sp. egg excretion.

Variation in the sex ratio of a low dimorphic polygynous species with high levels of maternal reproductive effort: Cuvier's gazelle

A population of 266 Cuvier's gazelles, descendants of two males and two females from the Western Sahara and living in the Estacion Experimental de Zonas Aridas, was analyzed. Results show that the energy cost of producing and rearing offspring, measured as offspring body weight, does not vary between males and females. But more males than females die during the 1st month of life. The advantages of producing one or the other sex are discussed. The cost of the parents' future reproductive success of producing male or female offspring was also investigated. Interbirth intervals following a twin male-female birth are longer than the other possibilities. However, no effects were observed of sex and litter size of the previous birth on sex and litter size of next birth nor on survival to 1 month of the next birth. Also no relationships were observed when we compared the components of the lifetime reproductive success of mothers (mother's longevity, fecundity, 1 month survival rate, abortion rate and age at firs...

The determinants of social status and the effect of female rank on reproductive success in Dama and Cuvier's gazelles

The social organization and the potential correlates of social status were investigated in 18 adult female Dama gazelles and 23 adult female Cuvier's gazelles living in captivity at the Estacion Experimental de Zonas Aridas in Almen'a (Spain). A linear hierarchy, positively correlated with age, was observed in Cuvier's gazelles but not in Dama gazelles. Physical characteristics (birth weight, adult weight, body length and horn length) had no effect on the social status of Dama gazelles, but adult body weight and horn size are good indicators of social status in Cuvier's gazelles. High social status was reinforced by aggression for both Dama and Cuvier's gazelles, but in Dama gazelles dominance was contested by the submissive. After the stability of dominance ranks was established, the effects of social status on the components of reproductive success were analysed (age at first birth, fecundity and annual survival of offspring). Results showed a reduction in fecundity and offspring survival and an increas...