Samstag, 13. Dezember 2014

Internet-Pornography:

There is a lot discussion if pornography addiction is a real addiction or a pseudo-addiction. But there are more interesting questions: (A) does internet-pornography have any influence on the mating patterns of Western societies? ... and if it does: (B) how strong is that influence?

Speculation about the effects of pornography consumption: (o) a weakening of the urge for romantic attachment + a stregthening of the urge for sexual pleasure;  (o) a weakening of long-term mating strategies + a strengthening of short-term mating strategies / promiscuous tendencies; etc.

[Mating patterns are of great interest, because from a biological point of view the future of societies is primarily determined by their mating patterns.]

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-> Mangan's: Marriage rate declining due to pornPornography;

Dienstag, 9. Dezember 2014

Primate Mating Patterns:











full size: click at the image








A phylogenetic scheme of Simiiformes at the genus level. The various colors correspond to the predominant social mating system.


Source:
Sexual selection and the evolution of behavior, morphology, neuroanatomy and genes in humans and other primates
Roscoe Stanyon & Francesca Bigoni 

Montag, 8. Dezember 2014

>Reason must approach nature with the view, indeed, of receiving information from it, not, however, in the character of a pupil, who listens to all that his master chooses to tell him, but in that of a judge, who compels the witnesses to reply to those questions which he himself thinks fit to propose.<
Immanuel Kant

Montag, 1. Dezember 2014

Countries with more than one scientific Nobel Prize per million people


Countries with more than one scientific Nobel Prize per million people | via Brilliant Maps

(Scientific Nobel Prizes: Physics, Chemistry, Medicine, Economics;)

Invention versus Discovery:


"Scientific truth is universal, because it is only discovered by the human brain and not made by it, as art is."
Konrad Lorenz


"Invention is quite different from discovery. When we say that someone discovered a thing, we mean that it already existed beforehand: it was just not well-known - for example, America before Columbus. But when someone invents a thing - gunpowder, for example - that thing was not known at all before the artist who made it."
Immanuel Kant

Sonntag, 30. November 2014

Associations between Dopamine D4 Receptor Gene Variation with Both Infidelity and Sexual Promiscuity

Justin R. Garcia, James MacKillop, Edward L. Aller, Ann M. Merriwether, David Sloan Wilson, J. Koji Lum (Nov 2010)


Background

Human sexual behavior is highly variable both within and between populations. While sex-related characteristics and sexual behavior are central to evolutionary theory (sexual selection), little is known about the genetic bases of individual variation in sexual behavior. The variable number tandem repeats (VNTR) polymorphism in exon III of the human dopamine D4 receptor gene (DRD4) has been correlated with an array of behavioral phenotypes and may be predicatively responsible for variation in motivating some sexual behaviors, particularly promiscuity and infidelity.



Methodology/Principal Findings

We administered an anonymous survey on personal history of sexual behavior and intimate relationships to 181 young adults. We also collected buccal wash samples and genotyped the DRD4 VNTR. Here we show that individuals with at least one 7-repeat allele (7R+) report a greater categorical rate of promiscuous sexual behavior (i.e., having ever had a “one-night stand”) and report a more than 50% increase in instances of sexual infidelity.



Conclusions/Significance

DRD4 VNTR genotype varies considerably within and among populations and has been subject to relatively recent, local selective pressures. Individual differences in sexual behavior are likely partially mediated by individual genetic variation in genes coding for motivation and reward in the brain. Conceptualizing these findings in terms of r/K selection theory suggests a mechanism for selective pressure for and against the 7R+ genotype that may explain the considerable global allelic variation for this polymorphism.

Cooperative breeding and monogamy in mammalian societies

Cooperative breeding and monogamy in mammalian societies
Dieter Lukas & Tim Clutton-Brock (2012)


Abstract

Comparative studies of social insects and birds show that the evolution of cooperative and eusocial breeding systems has been confined to species where females mate completely or almost exclusively with a single male, indicating that high levels of average kinship between group members are necessary for the evolution of reproductive altruism. In this paper, we show that in mammals, the evolution of cooperative breeding has been restricted to socially monogamous species which currently represent 5 per cent of all mammalian species. Since extra-pair paternity is relatively uncommon in socially monogamous and cooperatively breeding mammals, our analyses support the suggestion that high levels of average kinship between group members have played an important role in the evolution of cooperative breeding in non-human mammals, as well as in birds and insects.