The effect of multiple paternity on genetic diversity during and after colonisation

In metapopulations, genetic variation of local populations is influenced by the genetic content of the founders, and of migrants following establishment. We analyse the effect of multiple paternity on genetic diversity using a model in which the highly promiscuous marine snail Littorina saxatilis expands from a mainland to colonise initially empty islands of an archipelago. Migrant females carry a large number of eggs fertilised by 1 - 10 mates. We quantify the genetic diversity of the population in terms of its heterozygosity: initially during the transient colonisation process, and at long times when the population has reached an equilibrium state with migration. During colonisation, multiple paternity increases the heterozygosity by 10 - 300 % in comparison with the case of single paternity. The equilibrium state, by contrast, is less strongly affected: multiple paternity gives rise to 10 - 50 % higher heterozygosity compared with single paternity. Further we find that far from the mainland, new mutations spreading from the mainland cause bursts of high genetic diversity separated by long periods of low diversity. This effect is boosted by multiple paternity. We conclude that multiple paternity facilitates colonisation and maintenance of small populations, whether or not this is the main cause for the evolution of extreme promiscuity in Littorina saxatilis.Comment: 7 pages, 5 figures, electronic supplementary materia

Multiple paternity and hybridization in two smooth-hound sharks

Multiple paternity appears to be a common trait of elasmobranch mating systems, with its occurrence likely driven by convenience, due to females seeking to minimize the stress of male harassment. Here we use molecular markers to analyse the frequency of multiple paternity in two related viviparous sharks, Mustelus mustelus and Mustelus punctulatus. We first applied molecular methods to assign pregnant females, embryos and additional reference adults (N\u2009=\u2009792) to one of the two species. Paternity analysis was performed using a total of 9 polymorphic microsatellites on 19 females and 204 embryos of M. mustelus, and on 13 females and 303 embryos of M. punctulatus. Multiple paternity occurs in both species, with 47% of M. mustelus and 54% of M. punctulatus litters sired by at least two fathers. Female fecundity is not influenced by multiple mating and in 56% of polyandrous litters paternity is skewed, with one male siring most of the pups. Genetic analyses also revealed hybridization between the two species, with a M. punctulatus female bearing pups sired by a M. mustelus male. The frequency of polyandrous litters in these species is consistent with aspects of their reproductive biology, such as synchronous ovulation and possible occurrence of breeding aggregations

Divergent trends in U.S. maternity and paternity leave, 1994–2015

OBJECTIVES: The objective is to determine the number and type of U.S. workers taking maternity or paternity leave. METHODS: This research analyzes secondary data from 1994 to 2015 from the Current Population Survey (CPS). The CPS surveys about 60,000 randomly selected households monthly and provides a publicly available ecological long-term series for measuring parental leave. RESULTS: The average month from 1994 to 2015 saw 273,000 women and 13,000 men on maternity or paternity leave. Maternity leave figures show no trend over 22 years. Paternity figures increase by a factor of three, but start from a small base. No national impact on maternity or paternity leave was observed after implementation of state laws which provided paid leave. About half (51.1%) of employees on maternity or paternity leave during 2015 received paid time off. The typical woman on maternity leave was older, more likely married, more likely white non-Hispanic and more educated than the typical woman who gave birth. CONCLUSION: While the US economy expanded dramatically since 1994, this improvement does not appear to have translated into more women taking maternity leave.  Accepted manuscrip

The Impact of Paternity Leave on Long-term Father Involvement

Using Norwegian registry data we investigate how paternity leave affects fathers’ long-term earnings. In 1993 Norway introduced a paternity quota of the paid parental leave. We estimate a difference-in-differences model which exploits differences in fathers' exposure to the paternity quota. Our analysis suggests that four weeks paternity leave during the child’s first year decreases fathers’ future earnings by 2.1 percent. Importantly, this effect persists up until our last point of observation when the child is five years old. The earnings effect is consistent with increased long-term father involvement, as fathers shift time and effort from market to home production. In an investigation of Norwegian time use data we find additional evidence for this hypothesis.father involvement, household production, parental leave

Getting Time Off: Access to Leave Among Working Parents

"Mommy, I don't feel good." "Honey, it's time to go to the hospital." When working parents, or parents-to-be, hear these phrases, their anxiety levels often increase. Not only because their children are sick or their partners are in labor, but also because they will have to find a way to keep their jobs while tending to their families' needs. Maternity and paternity leave, along with vacation, sick leave, and personal leave, help workers balance their responsibilities at home and at the office. This brief uses new data from the National Survey of America's Families (NSAF) to portray which working parents have access to paid and maternity/paternity leave.Although federal law guarantees job-protected, unpaid family leave to many workers, only three in five American workers are eligible to take this leave (Cantor et al. 2001). Moreover, no state or federal legislation requires employers to provide paid leave of any kind. Because access to leave is not universal, some caregivers do not fully realize the benefits of job-protected leave, namely job security and some flexibility to care for children.This analysis examines whether access to leave differs by socioeconomic characteristics. The data suggest that the majority of working parents can take maternity or paternity leave from their jobs. Although access to maternity/paternity leave varies with measures of economic well-being, it is much more equal than access to paid leave. Most poor workers, working welfare recipients, and working recent welfare leavers cannot take paid leave from their jobs. And those who can take paid leave typically have fewer days of paid leave than nonpoor workers or workers with no recent welfare experience. The relatively even distribution of access to maternity and paternity leave, compared with the uneven access to paid leave, could be an effect of the Family and Medical Leave Act of 1993 (FMLA)

Government response to consultation on choice and flexibility: Additional Paternity Leave and Pay

Sets out the Government's response to a public consultation on the legal and technical espects of the Additional Paternity Leave and Pay (APL&P) scheme

Child-Care in Norway: Use of Parental Leave by Fathers

An important feature of parental leave in Norway is that it allows significant sharing of leave between parents. Parents may take 54 weeks of leave and receive 80 per cent of previous earnings or 44 weeks of leave with 100 per cent of earnings, up to a ceiling amount. Nine weeks of total leave are, however, reserved for the mother and six weeks for the father and, as a general rule, these weeks cannot be transferred to the other parent. The remaining parental leave can be shared between parents. A reserved period of leave for fathers, known as the paternity quota, was introduced in 1993. Initially, this quota was four weeks. The paternity quota has been a great success and is utilized by 80–85 per cent of eligible fathers; however, very few fathers share gender-neutral parental leave. In this paper, we use register data to investigate factors that may influence fathers’ share of parental leave for children born in 2001. We find that married fathers use more leave than cohabitants. In addition, fathers’ education, mothers’ income and number of preschool children positively affect fathers’ use of the paternity quota and gender-neutral leave. Fathers’ workplace does not affect the use of the paternity quota but has a significant effect on the use of gender-neutral leave.Economics of Gender; Non-labor Discrimination; Public Policy.

Female economic dependence and the morality of promiscuity

This article is made available through the Brunel Open Access Publishing Fund. Copyright @ The Author(s) 2014.In environments in which female economic dependence on a male mate is higher, male parental investment is more essential. In such environments, therefore, both sexes should value paternity certainty more and thus object more to promiscuity (because promiscuity undermines paternity certainty). We tested this theory of anti-promiscuity morality in two studies (N = 656 and N = 4,626) using U.S. samples. In both, we examined whether opposition to promiscuity was higher among people who perceived greater female economic dependence in their social network. In Study 2, we also tested whether economic indicators of female economic dependence (e.g., female income, welfare availability) predicted anti-promiscuity morality at the state level. Results from both studies supported the proposed theory. At the individual level, perceived female economic dependence explained significant variance in anti-promiscuity morality, even after controlling for variance explained by age, sex, religiosity, political conservatism, and the anti-promiscuity views of geographical neighbors. At the state level, median female income was strongly negatively related to anti-promiscuity morality and this relationship was fully mediated by perceived female economic dependence. These results were consistent with the view that anti-promiscuity beliefs may function to promote paternity certainty in circumstances where male parental investment is particularly important