scholarly journals Intersexual conflict influences female reproductive success in a female-dispersing primate

2019 ◽  
Vol 73 (9) ◽  
Author(s):  
Marie L. Manguette ◽  
Andrew M. Robbins ◽  
Thomas Breuer ◽  
Emma J. Stokes ◽  
Richard J. Parnell ◽  
...  
Keyword(s):  
Reproductive Success ◽  
Sexual Coercion ◽  
Group Living ◽  
Negative Consequences ◽  
Male Behavior ◽  
Female Reproductive Success ◽  
Birth Rates ◽  
Secondary Dispersal ◽  
Western Lowland Gorillas ◽  
Offspring Mortality

Abstract In group-living mammals, individual efforts to maximize reproductive success result in conflicts and compromises between the sexes. Females utilize counterstrategies to minimize the costs of sexual coercion by males, but few studies have examined the effect of such behaviors on female reproductive success. Secondary dispersal by females is rare among group-living mammals, but in western gorillas, it is believed to be a mate choice strategy to minimize infanticide risk and infant mortality. Previous research suggested that females choose males that are good protectors. However, how much female reproductive success varies depending on male competitive ability and whether female secondary dispersal leads to reproductive costs or benefits has not been examined. We used data on 100 females and 229 infants in 36 breeding groups from a 20-year long-term study of wild western lowland gorillas to investigate whether male tenure duration and female transfer rate had an effect on interbirth interval, female birth rates, and offspring mortality. We found that offspring mortality was higher near the end of males’ tenures, even after excluding potential infanticide when those males died, suggesting that females suffer a reproductive cost by being with males nearing the end of their tenures. Females experience a delay in breeding when they dispersed, having a notable effect on birth rates of surviving offspring per female if females transfer multiple times in their lives. This study exemplifies that female counterstrategies to mitigate the effects of male-male competition and sexual coercion may not be sufficient to overcome the negative consequences of male behavior. Significance Individual reproductive success is maximized through conflicts and compromises between the sexes in social mammals. In species with high dimorphism, females can experience sexual coercion by males and develop counterstrategies to reduce these costs. We studied this link in western lowland gorillas, which exhibit female secondary dispersal, a strategy that is believed to reflect female choice for the protective abilities of males. We found that females are faced with the dilemma of staying with a silverback at the end of his tenure and risk higher infant mortality versus dispersing and suffering reproductive delays and lower birth rates. This study shows that female reproductive strategies, namely dispersal, used to counter the effects of sexual coercion by males are not sufficient to overcome the negative consequences of male behavior.

scholarly journals Motherly love curbs harm: maternal effects can modulate sexual conflict

2021 ◽  
Author(s):  
Roberto García-Roa ◽  
Gonçalo Faria ◽  
Daniel W.A. Noble ◽  
Pau Carazo
Keyword(s):  
Reproductive Success ◽  
Maternal Effects ◽  
Sexual Conflict ◽  
Evolutionary Biology ◽  
Good Genes ◽  
Negative Consequences ◽  
Female Reproductive Success ◽  
Offspring Quality ◽  
Male And Female ◽  
The Commons

Strong sexual selection frequently favours males that increase their reproductive success by harming females, with potentially negative consequences for the growth of populations. Understanding what factors may resolve this reproductive “tragedy of the commons” is a key question in evolutionary biology. Studies addressing the evolution of sexual conflict have so far considered direct effects on male and female reproductive success along with indirect genetic benefits (e.g. good genes) to females. Here, we model the evolution of male harm while incorporating male-induced maternal effects on offspring quality. We show that maternal effects can partially align male and female evolutionary interests, fostering cooperation between the sexes and significantly reducing optimal levels of male harm. This finding fits broadly with available evidence across the tree of life, opening a novel avenue to understand the evolution of sexual conflict.

scholarly journals Temporal changes in reproductive success and optimal breeding decisions in a long-distance migratory bird

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Cynthia Reséndiz-Infante ◽  
Gilles Gauthier
Keyword(s):  
Reproductive Success ◽  
Clutch Size ◽  
Environmental Changes ◽  
Migratory Bird ◽  
Laying Date ◽  
Negative Consequences ◽  
Breeding Phenology ◽  
Additional Time ◽  
Long Distance ◽  
Seasonal Decline

AbstractMany avian migrants have not adjusted breeding phenology to climate warming resulting in negative consequences for their offspring. We studied seasonal changes in reproductive success of the greater snow goose (Anser caerulescens atlantica), a long-distance migrant. As the climate warms and plant phenology advances, the mismatch between the timing of gosling hatch and peak nutritive quality of plants will increase. We predicted that optimal laying date yielding highest reproductive success occurred earlier over time and that the seasonal decline in reproductive success increased. Over 25 years, reproductive success of early breeders increased by 42%, producing a steeper seasonal decline in reproductive success. The difference between the laying date producing highest reproductive success and the median laying date of the population increased, which suggests an increase in the selection pressure for that trait. Observed clutch size was lower than clutch size yielding the highest reproductive success for most laying dates. However, at the individual level, clutch size could still be optimal if the additional time required to acquire nutrients to lay extra eggs is compensated by a reduction in reproductive success due to a delayed laying date. Nonetheless, breeding phenology may not respond sufficiently to meet future environmental changes induced by warming temperatures.

Significance of wounding to female reproductive success in Hawaiian monk seals (Monachus schauinslandi) at Laysan Island

1993 ◽  
Vol 71 (3) ◽  
pp. 469-474 ◽  
Author(s):  
Lisa M. Hiruki ◽  
Ian Stirling ◽  
William G. Gilmartin ◽  
Thea C. Johanos ◽  
Brenda L. Becker
Keyword(s):  
Reproductive Success ◽  
Adult Male ◽  
Reproductive Rate ◽  
Lactation Period ◽  
Female Reproductive Success ◽  
Monachus Schauinslandi ◽  
Lower Survival Rate ◽  
Adult Females ◽  
Pup Survival ◽  
Monk Seals

We studied reproductive rate, length of lactation period, pup survival, and mortality of injured and uninjured female Hawaiian monk seals (Monachus schauinslandi) on Laysan Island, northwestern Hawaiian Islands, in 1983 – 1989. The severity and timing of nonfatal injuries were influential in determining their effect on female reproductive success. There was a tendency towards a shorter mean lactation period and lower survival rate of pups for females with major injuries than for uninjured females. Females with minor injuries were similar to uninjured females in terms of reproductive rate, length of lactation, and pup survival. For females injured shortly before the birth of their pup or during lactation, pup survival was lower than for uninjured females, whereas for females injured during the year prior to pupping, measures of reproductive success were not significantly different from those for uninjured females. Immature (aged 4 – 8 years) females entering the reproductive population were injured by adult male seals significantly more often than females aged 0 – 3 years, but at a similar rate to adult females. The major effect of injuries on female reproductive success is an increase in female mortality: 87.5 % of the adult females (n = 16) that died on Laysan Island in 1983 – 1989 sustained injuries from adult male seals.

Female reproductive success in a species with an age-inversed hierarchy

2016 ◽  
Vol 11 (6) ◽  
pp. 433-446 ◽  
Author(s):  
Dorien DE VRIES ◽  
Andreas KOENIG ◽  
Carola BORRIES
Keyword(s):  
Reproductive Success ◽  
Female Reproductive Success

scholarly journals Fitness of breeders in social Damaraland mole-rats is independent of group size

2021 ◽  
Author(s):  
Jack Thorley ◽  
Hanna Bensch ◽  
Kyle Finn ◽  
Tim Clutton-Brock ◽  
Markus Zöttl
Keyword(s):  
Reproductive Success ◽  
Group Size ◽  
Survival Rates ◽  
Group Living ◽  
Adult Survival ◽  
High Survival ◽  
Successful Reproduction ◽  
Related Group ◽  
Group Members ◽  
Using Data

Damaraland mole-rats (Fukomys damarensis) are usually viewed as an obligatorily group living eusocial species in which successful reproduction is dependent on reproductive altruism of closely related group members. However, the reproductive ecology of social mole-rats in their natural environment remains poorly understood and it is unclear to what extent successful reproduction is dependent on assistance from other group members. Using data from a 7-year field study of marked individuals, we show that, after dispersal from their natal group, individuals typically settled alone in new burrow systems where they enjoyed high survival rates, and often remained in good body condition for several years before finding a mate. Unlike most other eusocial or singular cooperative breeders, we found that Damaraland mole-rats reproduced successfully in pairs without helpers and experimentally formed pairs had the same reproductive success as larger established groups. Overall there was only a weak increase in reproductive success with increasing group size and no effect of group size on adult survival rates across the population. Juveniles in large groups grew faster early in life but their growth rates declined subsequently so that they eventually plateaued at a lower maximum body mass than juveniles from small groups. Taken together, our data suggest that the fitness benefits of group living to breeders are small and we suggest that extended philopatry in Damaraland mole-rats has evolved because of the high costs and constraints of dispersal rather than because of strong indirect benefits accrued through cooperative behaviour.

scholarly journals The Current Demographic Scenario

2018 ◽  
Vol 13 (2) ◽  
pp. 109-115
Author(s):  
Isidro Fierro Ulloa
Keyword(s):  
Large Population ◽  
Public Health Education ◽  
International Organization ◽  
Capital City ◽  
Negative Consequences ◽  
Birth Rates ◽  
The World ◽  
Fast Pace ◽  
And Migration ◽  
Demographic Impact

This research paper is aimed at thinking about the problem that the current demographic scenario means for mankind because of the excessive increase on the birth rates in poorest social class in the globe. This overpopulation is consuming the global resources at a fast pace and it is taking the world to its limits. This paper focuses on the increase of the population in India country 1.350 million inhabitants and more specifically on New Dahli its capital city whose large population is expected to be larger than China population by 2030. This study used the inductive approach to research to analyze the globe cities and its many problems which must become business and migration centers from populations focused on single cities which are making economic poverty, public health, education system and jobs a problem difficult to cope with. This approach allows to be in line with the current demographic scenario which uses the international organization data to monitor the global overpopulation. The results showed that a timely control over birth rates and the citizen´s education might minimize the demographic impact that the world currently experiences. In short, this situation should be regarded as the problem of the century one due to the negative consequences that should be efficiently treated in the ethics, social, politics and human.

scholarly journals Male and female reproductive success in natural and anthropogenic populations of Malaxis monophyllos (L.) Sw. (Orchidaceae)

2015 ◽  
Vol 39 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Edyta Jermakowicz ◽  
Beata Ostrowiecka ◽  
Izabela Tałałaj ◽  
Artur Pliszko ◽  
Agata Kostro-Ambroziak
Keyword(s):  
Reproductive Success ◽  
Fruit Set ◽  
Natural Populations ◽  
Floral Display ◽  
Natural Habitats ◽  
Female Reproductive Success ◽  
Male And Female ◽  
Demographic Processes ◽  
Preliminary Study ◽  
Effective Pollinators

Abstract In the presented study, male and female reproductive success was analyzed in relation to the population size, floral display and pollinators’ availability in natural and anthropogenic populations of the orchid Malaxis monophyllos (L.) Sw. Our results indicated significant differences between all investigated populations in parameters of floral display, including heights and number of flowers per inflorescence, as well the number of flowering individuals and their spatial structure. Additionally, populations differed both in male (pollinia removal) and female (fruit set) reproductive success, but only the fruit set clearly differentiated anthropogenic and natural populations. Despite the average flower number per plant being significantly higher in two of the anthropogenic populations, it was not related to the fruits set, which was significantly lower there. Moreover, our preliminary study concerning the potential pollinators of M. monophyllos showed a higher contribution of flies in natural habitats than in anthropogenic ones. Thus, we can suspect that the main factors influencing the level of female reproductive success in M. monophyllos populations are abundance of effective pollinators, as well as flower visitors, which may have resulted in a different level of pollen discounting in populations. Therefore, further studies concerning breeding system and pollination as important forces that shape demographic processes in M. monophyllos populations are necessary. Our results also indicate that suitable conservation methods in M. monophyllos should always include the preservation of potential pollinators, especially in these new, secondary habitats.

Sign in / Sign up

Export Citation Format

Share Document