Assortative Mating

The evolutionary history of three out of four birds traditionally classified into the genus Rhodopechys birds has been studied by comparing their mitochondrial cytochrome b DNA sequence with that of greenfinches and other genus Carduelis finches. The desert finch (Rhodopechys obsoleta) or a sister extinct species seems to have existed about 6 million years ago in Asian and perhaps African desert-like areas. This bird has no molecular relationship with other Rhodopechys birds and seems to have given rise to the greenfinches radiation, probably by allopatry of marginal or isolated groups; the latter would have evolved to green plumage colours and more simple song modulations (i.e., greenfinches). The possible role of assortative mating and the newly postulated acquired phenotypic characters in greenfinches speciation are discussed.

Knowledge of evolutionary influences on patterns of human mating, social interactions, and differential health is increasing, yet these insights have rarely been applied to historical analyses of human population dynamics. The genetic and evolutionary forces behind biases in interethnic mating and in the health of individuals of different ethnic groups in Latin America and the Caribbean since the European colonization of America are still largely ignored. We discuss how historical and contemporary sociocultural interactions and practices are strongly influenced by population-level evolutionary forces. Specifically, we discuss the historical implications of functional (de facto) polygyny, sex-biased admixture, and assortative mating in Latin America. We propose that these three evolutionary mechanisms influenced mating patterns, shaping the genetic and cultural landscape across Latin America and the Caribbean. Further, we discuss how genetic differences between the original populations that migrated at different times into Latin America contributed to their accommodation to and survival in the different local ecologies and interethnic interactions. Relevant medical and social implications follow from the genetic and cultural changes reviewed.

This paper uses a conditional logit model to analyze empirically how individuals sort themselves through marriage into households in India and the U.S. The results support positive assortative mating of spouses with respect to age and schooling. We find no evidence in favor of Becker's theory of labor market specialization in couples. Moreover, while similarity in age is the strongest predictor of marital choice in India, education of a prospective spouse plays a more important role in the U.S. Finally, we find that while dowry increases the likelihood of women marrying men with characteristics dissimilar to their own, availability of a mate has a positive effect on the degree of stratification in India.

Any biological species of biparental organisms necessarily includes, and is fundamentally dependent on, sign processes between individuals. In this case, the natural category of the species is based on family resemblances (in the Wittgensteinian sense), which is why a species is not a natural kind. We describe the mechanism that generates the family resemblance. An individual recognition window and biparental reproduction almost suffice as conditions to produce species naturally. This is due to assortativity of mating which is not based on certain individual traits, but on the difference between individuals. The biosemiotic model described here explains what holds a species together. It also implies that boundaries of a species are fundamentally fuzzy, and that character displacement occurs in case of sympatry. Speciation is a special case of discretisation that is an inevitable result of any communication system in work. The biosemiotic mechanism provides the conditions and communicative restrictions for the origin and persistence of diversity in the realm of living (communicative and semiotic) systems.

Numerous studies proved that people tend to select partners that are similar to them with regard to many social and psychological variables. Even though this effect was also found for personality, results are inconsistent and reveal convergence coefficients ranging from negative over zero- to positive correlations. The present study thus aims to investigate personality congruence between spouses and to examine (a) which dimensions show a high degree of congruence and which do not and (b) in how far this congruence is moderated by the marriage duration. Analyses were based on 6,909 couples who are representative for the German adult population. Results reveal that among the Big Five dimensions, there are strong differences in spouses’ congruences. While for Extraversion and Emotional Stability, congruence is close to zero, correlations averaging at .30 are found for Agreeableness, Conscientiousness, and Openness. The spouses’ congruences in these three dimensions also increase over marriage duration from a mean of r = .22 to r = .40.

Despite their reputation for taking advantage of other people, previous research shows that psychopathic individuals
are attractive for short-term relationships. Furthermore, individuals with psychopathic traits have been
found to be attracted to other psychopathic persons in both short and long-term relationships. The current
study (N = 258), is the first to extend the investigation further by examining whether these findings pertain
to the affective (i.e., primary) or behavioural (i.e., secondary) aspects of psychopathy, and if this varies according
to sex. Using a series of personality profiles, we found that men and women evaluated individuals higher in primary
or secondary psychopathic traits unattractive for both short and long-term relationships. However, those
individuals higher in primary and secondary psychopathic traits found similar partners attractive in short and
long-termrelationships, and thiswas strongest inwomen higher in primary psychopathic traits for long-termrelationships,
and inwomen higher in secondary psychopathic traits for short and long-term relationships. Results
are discussed from an evolutionary theoretical perspective.

Objective: Assortative mating for adiposity increases the genetic burden on offspring, but its causes remain unclear. One hypothesis is that people who have high adiposity find other people with obesity more physically attractive than lean people. Methods: The attractiveness of sets of images of males and females who varied in adiposity were rated by opposite sex subjects (559 males and 340 females) across 12 countries. Results: There was tremendous individual variability in attractiveness ratings. For female attractiveness, most males favored the leanest subjects, but others favored intermediate fatness, some were indifferent to body composition, and others rated the subjects with obesity as most attractive. For male images rated by females, the patterns were more complex. Most females favored subjects with low levels of adi-posity (but not the lowest level), whereas others were indifferent to body fatness or rated the images depicting individuals with obesity as the most attractive. These patterns were unrelated to rater BMI. Among Caucasian males who rated the images of the thinnest females as being more attractive, the magnitude of the effect depended on rater BMI, indicating limited " mutual attraction. " Conclusions: Individual variations in ratings of physical attractiveness were broadly unrelated to rater BMI and suggest that mutual attraction is an unlikely explanation for assortative mating for obesity.

It has been estimated that Lake Malawi, Africa, contains 500–650 endemic species of cichlid fishes, the largest number of vertebrate species endemic to any comparable sized area on the planet. As many of these putative species cannot be distinguished anatomically, these estimates of species richness depend to a great extent on the assumption that sympatrically occurring male colour morphs represent biological species. We have tested this assumption using a combination of behavioural observations of courtship and microsatellite DNA analysis for six putative species of the Pseudotropheus (Tropheops) complex and three of the Pseudotropheus (Maylandia) complex occurring sympatrically at Nkhata Bay. We were unable to demonstrate assortative courtship for the species pairs Pseudotropheus (Maylandia) zebra/P. ‘gold zebra’ or P. (Tropheops) ‘band’/P. (T.) ‘rust’ because we were unable to distinguish between the females of these taxa. All other taxa showed clear assortative courtship, except for P. (T.) ‘deep’, a deep-water species which was rarely observed. Fixation indices (θST for the infinite allele model, and RST for the stepwise mutation model) calculated from six microsatellite DNA loci demonstrated significant deviations from panmixia in all pairwise comparisons of putative species, indicating little or no gene flow between populations. All taxa showed high levels of allelic diversity providing evidence that genetic bottlenecking may have been of limited importance in the speciation process. Assortative mating among taxa differing only in male colouration is supportive of theories that speciation in these fishes has been driven by sexual selection by female choice.

THE ENIGMA OF THE WIFE/SISTER EPISODES IN GENESIS IS RESOLVED...

Answering the question:

“Should we not therefore conclude that God should have also kept Pharaoh from touching her? The logic is compelling, the same Abraham and Sarah, the same conditions, the same God.”

With references from: Richard Lynn's The Chosen People, A Study of Jewish Intelligence and Achievement, Washington Summit Publishers, A National Policy Institute Book 2011

Assortative mating, or the tendency for individuals with similar phenotypes to mate more frequently than expected by chance, has been reported for a variety of complex traits, including many neuropsychiatric disorders. Although assortative mating has been reported in affective disorders, the studies done to date have been inconclusive. This study attempts to assess the degree of assortative mating in individuals

We use a multigenerational perspective to investigate how families reproduce and pass their educational advantages to succeeding generations. Unlike traditional mobility studies that have typically focused on one-sex influences from fathers to sons, we rely on a two-sex approach that accounts for interactions between males and females-the process in which males and females mate and have children with those of similar educational statuses and jointly determine the educational status attainment of their offspring. Using data from the Panel Study of Income Dynamics, we approach this issue from both a short-term and a long-term perspective. For the short term, grandparents' educational attainments have a direct association with grandchildren's education as well as an indirect association that is mediated by parents' education and demographic behaviors. For the long term, initial educational advantages of families may benefit as many as three subsequent generations, but such advantages are later offset by the lower fertility of highly educated persons. Yet, all families eventually achieve the same educational distribution of descendants because of intermarriages between families of high-and low-education origin.