Karrierefrauen und das Kinderkriegen

Ich war kürzlich bei einem befreundeten Ehepaar zu Besuch, die eine etwa 10 Monate alte Tochter haben.

Beide sind Rechtsanwälte und beide in Kanzleien tätig.Ein Beruf, bei dem man wohl kaum davon ausgehen kann, dass die Frau sich leicht unterbuttern läßt.

Seit das Kind auf der Welt ist tritt sie beruflich kürzer. Mit dem Stillen und allem drum und dran geht es eben nicht anders, auch wenn er ihr viel abnimmt, wenn er dann später nach Hause kommt.

Als ich dar war, hatte das Kind etwas Fieber und zudem zahnte es wohl und war demnach recht unwirsch, aber, wie an dem gut entwickelten Organ erkennbar durchaus noch bei Kräften. Sogar sehr bei Kräften, denn sie hatte die Nacht durchgemacht und wenig Tendenzen leiser zu werden.

Die Mutter war recht fertig, aber wenn man das Kind aus ihren Armen nahm, damit sie etwas Ruhe hatte, dann wurde das Schreien lauter und die Pausen dazwischen kürzer. Menschenbabies haben eben auch eine gewisse Prägung auf eine Hauptbezugsperson und das wird schon durch das Stillen meist die Mutter.

Sie wollen noch ein zweites Kind und nach Wunsch der Mutter auch evtl. noch ein drittes. Dann wird sie wohl ganz aufhören zu arbeiten, weil es mit den Kindern zuviel wird. Eine andere Aufteilung können sich beide nicht vorstellen.

Scheint mir nicht untypisch zu sein.

Schönheit und Vergebung

Eine Studie zu unser Wahrnehmung von schönen Leuten:

Two studies examined the influence of a female offender’s level of physical attractiveness on forgiveness. In Study 1, an apology offered to a male participant (role-playing a victim) by an attractive female offender was more effective at increasing forgiveness compared to the same apology offered by a less attractive offender. In contrast, female participants displayed the opposite pattern, responding more positively to the less attractive offender. Study 2 revealed that this effect was mediated by participants‘ judgments about the quality of the apology received. Male participants judged the apology as higher in quality when it was offered by the attractive offender, whereas female participants rated the apology as higher quality when it was offered by the less attractive offender.

Source: „Is beauty a gift or a curse? The influence of an offender’s physical attractiveness on forgiveness“ from Personal Relationships

Würde also bedeuten, dass schöne Frauen sich mehr erlauben können, während Frauen bei schönen Männern skeptischer sind. Das erklärt, die Skeptik vieler weiblicher Leser dieses Blogs 😉

Eine Erklärung wäre, dass Männer bei schönen Frauen nicht viel zu verlieren hatten, weil sie die Kosten einer Schwangerschaft abwälzen können. Die Frauen hingegen hatten, weil der Mann auch für andere Frauen attraktiv war, eher etwas zu verlieren.

Unterschiede in der Verteilung der Intelligenz bei Männern und Frauen

Terminator macht auf einige Studien zur Verteilung der Intelligenz innerhalb der Geschlechter aufmerksam:

Brother–sister differences in the g factor in intelligence: Analysis of full, opposite-sex siblings from the NLSY1979 Original Research Article

Intelligence, Volume 35, Issue 5, September-October 2007, Pages 451-456

Ian J. Deary, Paul Irwing, Geoff Der, Timothy C. Bates

Abstract

There is scientific and popular dispute about whether there are sex differences in cognitive abilities and whether they are relevant to the proportions of men and women who attain high-level achievements, such as Nobel Prizes. A recent meta-analysis (Lynn, R., and Irwing, P. (2004). Sex differences on the progressive matrices: a meta-analysis. Intelligence, 32, 481–498.), which suggested that males have higher mean scores on the general factor in intelligence (g), proved especially contentious. Here we use a novel design, comparing 1292 pairs of opposite-sex siblings who participated in the US National Longitudinal Survey of Youth 1979 (NLSY1979). The mental test applied was the Armed Services Vocational Aptitude Battery (ASVAB), from which the briefer Armed Forces Qualification Test (AFQT) scores can also be derived. Males have only a marginal advantage in mean levels of g (less than 7% of a standard deviation) from the ASVAB and AFQT, but substantially greater variance. Among the top 2% AFQT scores, there were almost twice as many males as females. These differences could provide a partial basis for sex differences in intellectual eminence.

Sex-related differences in general intelligence g, brain size, and social status Original Research Article

Personality and Individual Differences, Volume 39, Issue 3, August 2005, Pages 497-509

Helmuth Nyborg

Abstract

The question of a sex difference in intelligence has long divided the experts. IQ researchers sum standardized subtest scores to calculate intelligence in general, and find that males outscore females by about 3.8 points, whereas factor analysts derive the g factor scores from intertest-correlations and find no consistent sex differences in general intelligence. The latter finding is puzzling, as males have larger average brains than females, and brain size correlates .30–.45 with g (and IQ). Males thus “ought” to score a higher g than females.

The present study addressed this paradox by testing four hypotheses: (1) Inadequate analyses explain why researchers get inconsistent results, (2) The proper method will identify a male g lead, (3) The larger male brain “explains” the male g lead, (4) The higher male g average and wider distribution transform into an exponentially increased male–female ratio at the high end of the g distribution, and this largely explains male dominance in society.

All four hypotheses obtained support and explain in part why relatively few males dominate the upper strata in all known societies. The confirmation of hypothesis 3 suggests that the brain size—intelligence–dominance link may be partly biological.

Testing the developmental theory of sex differences in intelligence on 12–18 year olds Original Research Article

Personality and Individual Differences, Volume 36, Issue 1, January 2004, Pages 75-82

Roberto Colom, Richard Lynn

Abstract

The consensus view states that there are no sex differences in intelligence. However, Lynn (1994, 1999) has formulated a developmental theory of sex differences in intelligence that challenges that view. The theory states that boys and girls mature at different rates such that the growth of girls accelerates at the age of about 9 years and remains in advance of boys until 14–15 years. At 15–16 years the growth of girls decelerates relative to boys. As boys continue to grow from this age their height and their mean IQs increase relative to those of girls. This paper presents new evidence for the theory from the Spanish standardization sample of the fifth edition of the DAT. 1027 boys and 924 girls between 12 and 18 years were tested. The general trend shows that girls do better at the younger ages and their performance declines relative to boys among older age groups, which supports the developmental theory. The sex difference for the DAT as a whole for 18 year olds is a 4.3 IQ advantage for boys, very close to the advantage that can be predicted from their larger brain size (4.4 IQ points). The profile of sex differences in abilities among the Spanish sample is closely similar to that in the United States and Britain, which is testimony to the robustness of the difference in these different cultures.

Sex differences in brain size, stature and intelligence in children and adolescents: some evidence from Estonia Original Research Article

Personality and Individual Differences, Volume 29, Issue 3, 1 September 2000, Pages 555-560

Richard Lynn, Juri Allik, Olev Must

Abstract

Sex differences in brain size and stature decrease from the age of 7 through 13–14 years and increase from the age of 15 through 18 years in Estonia, as they do in the United States. Sex differences in intelligence show a somewhat similar decrease and increase although they do not move precisely in synchrony with the morphological trends. The results are interpreted as suggesting that sex differences in maturation determine the magnitude of sex differences in physical and mental development during childhood and adolescence.

Do sex differences in a faceted model of fluid and crystallized intelligence depend on the method applied? Original Research Article

Intelligence, Volume 38, Issue 1, January-February 2010, Pages 101-110

Ricarda Steinmayr, André Beauducel, Birgit Spinath

Abstract

Recently, different methodological approaches have been discussed as an explanation for inconsistencies in studies investigating sex differences in different intelligences. The present study investigates sex differences in manifest sum scores, factor score estimates, and latent verbal, numerical, figural intelligence, as well as fluid and crystallized intelligence as measured by the German Intelligence-Structure-Test 2000-R (IST 2000-R; Liepmann, Beauducel, Brocke, & Amthauer, 2007). The not population-representative sample consisted of 977 German 11th and 12th graders enrolled in a “Gymnasium” (551 female; mean age: M = 16.70; SD = 0.65) who completed the IST 2000-R. Sex differences in fluid and crystallized intelligence were not influenced by the method applied with men performing better than women. However, extent and direction of sex differences in verbal, numerical, and figural intelligence differed by the method applied. Whereas there was a male advantage in all three factors measured as manifest sum scores, women performed better in verbal intelligence as measured by factor scores or as latent variables. Effect sizes of sex differences in numerical and figural intelligence were also greatly reduced when applying the latter two methods. Results are discussed with regard to their theoretical and practical implications.

Factor structure and sex differences on the Wechsler Preschool and Primary Scale of Intelligence in China, Japan and United States Original Research Article

Personality and Individual Differences, Volume 50, Issue 8, June 2011, Pages 1222-1226

Jianghong Liu, Richard Lynn

Abstract

This study presents data on the factor structure of the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) and sex and cultural differences in WPPSI test scores among 5- and 6-year-olds from China, Japan, and the United States. Results show the presence of a verbal and nonverbal factor structure across all three countries. Sex differences on the 10 subtests were generally consistent, with a male advantage on a subtest of spatial abilities (Mazes). Males in the Chinese sample obtained significantly higher Full Scale IQ scores than females and had lower variability in their test scores. These observations were not present in the Japan and United States samples. Mean Full Scale IQ score in the Chinese sample was 104.1, representing a 4-point increase from 1988 to 2004.

A longitudinal study of sex differences in intelligence at ages 7, 11 and 16 years Original Research Article

Personality and Individual Differences, Volume 51, Issue 3, August 2011, Pages 321-324

Richard Lynn, Satoshi Kanazawa

Abstract

This paper presents the results of a longitudinal study of sex differences in intelligence as a test of Lynn’s (1994) hypothesis that from the age of 16 years males develop higher average intelligence than females. The results show that at the ages of 7 and 11 years girls have an IQ advantage of approximately 1 IQ point, but at the age of 16 years this changes in the same boys and girls to an IQ advantage of 1.8 IQ points for boys.

Intelligence and neural efficiency: Further evidence of the influence of task content and sex on the brain–IQ relationship Original Research Article

Cognitive Brain Research, Volume 25, Issue 1, September 2005, Pages 217-225

Aljoscha C. Neubauer, Roland H. Grabner, Andreas Fink, Christa Neuper

Abstract

In the field of physiological study of human intelligence, strong evidence of a more efficient operation (i.e., less activation) of the brain in brighter individuals (the neural efficiency hypothesis) can be found. Most studies in this field have used single, homogeneous tasks and have not examined sex differences. In analyzing the extent of Event-related Desynchronization (ERD) in the EEG during the performance of a verbal and a visuo-spatial task, we recently found that males and females display neural efficiency primarily in the domain where they usually perform better (i.e., verbal in females and spatial in males; cf. A.C. Neubauer, A. Fink, D.G. Schrausser, Intelligence and neural efficiency: the influence of task content and sex on brain–IQ relationship. Intelligence, 30 (2002) 515–536). However, this interpretation was complicated by differences in the complexity of the two tasks. By using a verbal (semantic) and a spatial (rotation) task of comparable complexity in this research, we sought to replicate and extend our earlier findings by additionally considering the individual differences in intelligence structure and the topographical distribution over the cortex. Findings were similar to the previous study: Females (n = 35) display neural efficiency (i.e., less brain activation in brighter individuals) primarily during the verbal task, males (n = 31) in the spatial task. However, the strength of this brain activation–IQ relationship varies with the intelligence factor: In males, the highest correlations were observed for spatial IQ, in females for verbal IQ. Furthermore, the sexes displayed topographical differences of neural efficiency patterns.

Sex differences in mental abilities: g masks the dimensions on which they lie Original Research Article

Intelligence, Volume 35, Issue 1, January-February 2007, Pages 23-39

Wendy Johnson, Thomas J. Bouchard Jr.

Abstract

Empirical data suggest that there is at most a very small sex difference in general mental ability, but men clearly perform better on visuospatial tasks while women clearly perform better on tests of verbal usage and perceptual speed. In this study, we integrated these overall findings with predictions based on the Verbal–Perceptual–Rotation (VPR) model ([Johnson, W., and Bouchard, T. J. (2005a). Constructive replication of the visual–perceptual–image rotation (VPR) model in Thurstone’s (1941) battery of 60 tests of mental ability. Intelligence, 33, 417–430.; Johnson, W., and Bouchard, T. J. (2005b). The structure of human intelligence: It’s verbal, perceptual, and image rotation (VPR), not fluid and crystallized. Intelligence, 33. 393–416.]) of the structure of mental abilities. We examined the structure of abilities after removing the effects of general intelligence, identifying three underlying dimensions termed rotation–verbal, focus–diffusion, and memory. Substantial sex differences appeared to lie along all three dimensions, with men more likely to be positioned towards the rotation and focus poles of those dimensions, and women displaying generally greater memory. At the level of specific ability tests, there were greater sex differences in residual than full test scores, providing evidence that general intelligence serves as an all-purpose problem solving ability that masks sex differences in more specialized abilities. The residual ability factors we identified showed strong genetic influences comparable to those for full abilities, indicating that the residual abilities have some basis in brain structure and function.

Sex, masculinity—feminity, and intelligence Original Research Article

Intelligence, Volume 1, Issue 2, April 1977, Pages 218-233

George S. Welsh, Donald H. Baucom

Abstract

Masculine and feminine subgroups of males and females were selected from samples of high school and college students on the basis of composite scores from several M—F scales. They were compared on intelligence as measured by a verbal test, Terman’s Concept Mastery Test, and a nonverbal test, D-48. Results did not support previous findings of sex differences in intelligence but showed that masculine subgroups of both sexes scored higher of the nonverbal test.

Sex differences in mental rotation and spatial visualization ability: Can they be accounted for by differences in working memory capacity? Original Research Article

Intelligence, Volume 35, Issue 3, May-June 2007, Pages 211-223

Scott Barry Kaufman

Abstract

Sex differences in spatial ability are well documented, but poorly understood. In order to see whether working memory is an important factor in these differences, 50 males and 50 females performed tests of three-dimensional mental rotation and spatial visualization, along with tests of spatial and verbal working memory. Substantial differences were found on all spatial ability and spatial working memory tests (that included both a spatial and verbal processing component). No significant differences were found in spatial short-term memory or verbal working memory. In addition, spatial working memory completely mediated the relationship between sex and spatial ability, but there was also a direct effect of sex on the unique variance in three-dimensional rotation ability, and this effect was not mediated by spatial working memory. Results are discussed in the context of research on working memory and intelligence in general, and sex differences in spatial ability more specifically.

Sex differences on the WISC-R in Mauritius Original Research Article

Intelligence, Volume 33, Issue 5, September-October 2005, Pages 527-533

Richard Lynn, Adrian Raine, Peter H. Venables, Sarnoff A. Mednick, Paul Irwing

Abstract

Sex differences on the WISC-R (Wechsler Intelligence Scale for Children-Revised) are examined in a sample of 1258 11 year olds in Mauritius. Boys obtained a significantly higher Full Scale IQ by 5.8 IQ points. Boys obtained a higher Performance IQ by 6.5 IQ points and a higher Verbal IQ by 1.0 IQ points. On the subtests, girls obtained a significantly higher mean on Coding while boys obtained significantly higher means on Similarities, Picture Completion, Block Design, Object Assembly and Mazes. There was no significant sex difference on Digit Span. Two methods were adopted for determining whether boys had an advantage on Spearman’s g. First, calculated from the first principal component of a principal components analysis, boys had an advantage on Spearman’s g of 6.15 IQ points. Second, using the method of entering the sex difference on each of the subtests as point-biserial correlations, including these in the full matrix of subtest correlations for factor analysis and examining the factor loading of sex on g produced a correlation between sex and g of .224, the equivalent of a sex difference of 6.9 IQ points. Thus the sex difference on the Full Scale IQ was found to be a good approximate measure of the difference in g. The pattern of sex differences in Mauritius is compared with that in eight other countries and found to be generally similar, although the boys’ advantage is greater in Mauritius than elsewhere. The variance in boys is slightly greater than in girls, but is only significant for Block Design.

Intelligence, sex and psychomotor performance Original Research Article

Personality and Individual Differences, Volume 3, Issue 4, 1982, Pages 457-459

Jitendra Mohan, Meena Sehgal, Anuradha Bhandari

Abstract

This experiment investigated the effect of intelligence and sex on two simple psychomotor performance tests—Backward Figure Writing (BFW) and Backward Alphabet Writing (BAW) in 180 high-school students (90 boys and 90 girls). Three levels of intelligence, high, medium and low were taken. Ss being first matched on Extraversion and Neuroticism. Each S worked for 5 min in pre-test period, rested for 1 min and again worked for 2 min in post-rest period. Results indicated that in pre- and post-rest BFW, increase in speed of response was a direct function of increase in intelligence. Similar results were obtained in pre-rest BAW. In post-rest BAW, however, highest performance scores were obtained by the group, average in intelligence, followed by high and low intelligence groups. Sex did not emerge as a significant determiner of performance in BFW. In BAW, means favoured boys in both pre- and post-rest conditions and the F-ratio for sex emerged significant in post-rest BAW only. None of the interactions emerged as significant. The comparison of effects in two independent variables indicated the task-specific nature of various psychomotor tasks.

Sex differences on the progressive matrices: A meta-analysis Original Research Article

Intelligence, Volume 32, Issue 5, September-October 2004, Pages 481-498

Richard Lynn, Paul Irwing

Abstract

A meta-analysis is presented of 57 studies of sex differences in general population samples on the Standard and Advanced Progressive Matrices (SPM and APM, respectively). Results showed that there is no difference among children aged 6–14 years, but that males obtain higher means from the age of 15 through to old age. Among adults, the male advantage is 0.33d equivalent to 5 IQ points. These results disconfirm the frequent assertion than there are no sex differences on the progressive matrices and support a developmental theory that a male advantage appears from the age of 15 years. A meta-analysis of 15 studies of child samples on the Colored Progressive Matrices showed that among children aged 5–11 years boys have an advantage of 0.21d equivalent to 3.2 IQ points.

Sex differences on three factors identified in Raven’s Standard Progressive Matrices Original Research Article

Intelligence, Volume 32, Issue 4, July-August 2004, Pages 411-424

Richard Lynn, Jüri Allik, Paul Irwing

Abstract

Raven’s Standard Progressive Matrices (SPM) was administered to a sample of 2735 12- to 18-year-olds in Estonia. Both a scree test and the consistent Akaike information criterion (CAIC) indicated the presence of three significant factors. Exploratory and confirmatory factor analysis showed the loadings of the items on the three factors, which were identified as the gestalt continuation found by van der Ven and Ellis [Pers. Individ. Differ. 29 (2000) 45], verbal–analytic reasoning and visuospatial ability. Further analysis of the three factors showed a higher order factor identifiable as g. Examination of age by sex differences showed that on all four factors girls performed better than boys at the age of 12, there was no sex difference at age 14, while boys performed better than girls at the age of 17, although not significantly on visuospatial ability.

Sex differences in intelligence and brain size: A paradox resolved Original Research Article

Personality and Individual Differences, Volume 17, Issue 2, August 1994, Pages 257-271

Richard Lynn

Abstract

Males have larger brains than females, even when corrected for body size, and brain size is positively correlated with intelligence. This leads to the expectation that males should have higher average levels of intelligence than females. Yet the consensus view is that there is no sex difference in general intelligence. An examination of the literature shows that the consensus view is wrong. Among adults, males have slightly higher verbal and reasoning abilities than females and a more pronounced superiority on spatial abilities. If the three abilities are combined to form general intelligence, the mean for males is 4 IQ points higher than the mean for females. Among children up to the age of around 14 yr the sex differences are smaller because girls mature earlier than boys. The evolutionary selection pressures responsible for greater intelligence in males are discussed.

Sex differences in latent general and broad cognitive abilities for children and youth: Evidence from higher-order MG-MACS and MIMIC models Original Research Article

Intelligence, Volume 36, Issue 3, May-June 2008, Pages 236-260

Matthew R. Reynolds, Timothy Z. Keith, Kristen P. Ridley, Puja G. Patel

Abstract

Sex differences in the latent general and broad abilities underlying the Kaufman Assessment Battery for Children—Second Edition (KABC-II) were investigated for children and youth ages 6 through 18. The data were split into different age groups to account for changes due to differential development. Multi-group higher-order analysis of mean and covariance structures (MG-MACS) and multiple indicator-multiple cause (MIMIC) models were used to analyze these data. Boys consistently demonstrated a significant mean advantage on the latent visual–spatial ability (Gv) factor. A significant mean advantage was also found for boys on the latent crystallized ability (Gc) factor at all ages except for 17 and 18. Girls scored higher on the latent, higher-order g factor, at all ages, although this difference was statistically significant at only two age levels. An additional test, however, did not reveal a significant Age × Sex interaction effect, suggesting only main effects of Sex on Gv, Gc, and g.

Sex differences on the Progressive Matrices are influenced by sex differences on spatial ability Original Research Article

Personality and Individual Differences, Volume 37, Issue 6, October 2004, Pages 1289-1293

Roberto Colom, Sergio Escorial, Irene Rebollo

Abstract

The Progressive Matrices Test (PM) is considered an excellent measure of general intelligence or g. There are several studies showing that, on average, males score higher than females on the PM. However, some investigations have demonstrated that there are no sex differences in g. Why are there these contradictory findings? The visuo-spatial format of the PM could be favourable to the male performance, because (on average) males score higher than females on overall spatial ability. The present study administered the Advanced Progressive Matrices Test (APM) and the Spatial Rotation Test from the Primary Mental Abilities Battery (PMA) to a sample of 239 university undergraduates. Males outperformed females on both tests. However, the male advantage on the APM turned out to be non-significant when sex differences on spatial rotation were statistically controlled. It is suggested that sex differences on the PM could be a by-product of its visuo-spatial format.

In a Scottish standardisation sample of the Wechsler Adult Intelligence Scale-Revised, men have a mean IQ of 105.09 and women of 100.00. The higher average mean obtained by men is consistent with four other standardisation samples of the WAIS and WAIS-R.

Sex differential item functioning in the Raven’s Advanced Progressive Matrices: evidence for bias Original Research Article

Personality and Individual Differences, Volume 36, Issue 6, April 2004, Pages 1459-1470

Francisco J. Abad, Roberto Colom, Irene Rebollo, Sergio Escorial

Abstract

There are no sex differences in general intelligence or g. The Progressive Matrices (PM) Test is one of the best estimates of g. Males outperform females in the PM Test. Colom and García-López (2002) demonstrated that the information content has a role in the estimates of sex differences in general intelligence. The PM test is based on abstract figures and males outperform females in spatial tests. The present study administered the Advanced Progressive Matrices Test (APM) to a sample of 1970 applicants to a private University (1069 males and 901 females). It is predicted that there are several items biased against female performance, by virtue of their visuo-spatial nature. A double methodology is used. First, confirmatory factor analysis techniques are used to contrast one and two factor solutions. Second, Differential Item Functioning (DIF) methods are used to investigate sex DIF in the APM. The results show that although there are several biased items, the male advantage still remains. However, the assumptions of the DIF analysis could help to explain the observed results.

Sex differences on the WISC-R in New Zealand Original Research Article

Personality and Individual Differences, Volume 39, Issue 1, July 2005, Pages 103-114

Richard Lynn, David M. Fergusson, L. John Horwood

Abstract

Sex differences on the WISC-R were examined in a sample of 897 New Zealand children studied at ages 8 and 9 years. Boys scored significantly higher than girls on the subtests of information, vocabulary, block design and object assembly, while girls scored significantly higher on coding. Boys obtained slightly but not significantly higher scores on the verbal, performance and full scale IQs. The results were in general similar to the sex differences in the standardisation samples of the WISC-R in Scotland, the Netherlands and the United States.

Sex ratios in the most-selective elite US undergraduate colleges and universities are consistent with the hypothesis that modern educational systems increasingly select for conscientious personality compared with intelligence

Medical Hypotheses, Volume 73, Issue 2, August 2009, Pages 127-129

Bruce G. Charlton

Abstract

Summary

The main predictors of examination results and educational achievement in modern societies are intelligence (IQ – or general factor ‘g’ intelligence) and the personality trait termed ‘Conscientiousness’ (C). I have previously argued that increased use of continuous assessment (e.g. course work rather than timed and supervised examinations) and increased duration of the educational process implies that modern educational systems have become increasingly selective for the personality trait of Conscientiousness and consequently less selective for IQ. I have tested this prediction (in a preliminary fashion) by looking at the sex ratios in the most selective elite US universities. My two main assumptions are: (1) that a greater proportion of individuals with very high intelligence are men than women, and (2) that women are more conscientious than men. To estimate the proportion of men and women expected at highly-selective schools, I performed demonstration calculations based on three plausible estimates of male and female IQ averages and standard deviations. The expected percentage of men at elite undergraduate colleges (selecting students with IQ above 130 – i.e. in the top 2% of the population) were 66%, 61% and 74%. When these estimates were compared with the sex ratios at 33 elite colleges and universities, only two technical institutes had more than 60% men. Elite US colleges and universities therefore seem to be selecting primarily on the basis of something other than IQ – probably conscientiousness. There is a ‘missing population’ of very high IQ men who are not being admitted to the most selective and prestigious undergraduate schools, probably because their high school educational qualifications and evaluations are too low. This analysis is therefore consistent with the hypothesis that modern educational systems tend to select more strongly for Conscientiousness than for IQ. The implication is that modern undergraduates at the most-selective US schools are not primarily an intelligence elite, as commonly assumed, but instead an elite for Conscientious personality.

Sex differences in g: An analysis of the US standardization sample of the WAIS-III Original Research Article

Personality and Individual Differences, In Press, Corrected Proof, Available online 31 May 2011

Paul Irwing

Abstract

This study employed both hierarchical and Bi-factor multi-group confirmatory factor analysis with mean structures (MGCFA) to investigate the question of whether sex differences are present in the US standardization sample of the WAIS-III. The data consisted of age scaled scores from 2450 individuals aged from 16 to 89 years. The findings were more or less uniform across both analyses, showing a sex difference favoring men in g (0.19–0.22d), Information (0.40d), Arithmetic (0.37–0.39d) and Symbol Search (0.40–0.30d), and a sex difference favoring women in Processing Speed (0.72–1.30d).

Sex differences on elementary cognitive tasks despite no differences on the Wonderlic Personnel Test Original Research Article

Personality and Individual Differences, Volume 45, Issue 5, October 2008, Pages 429-431

Bryan J. Pesta, Sharon Bertsch, Peter J. Poznanski, William H. Bommer

Abstract

Whether males and females differ in general mental ability (GMA) remains an open question. Complicating the issue is that standardized IQ tests are constructed to minimize sex differences. We propose a potential solution whereby GMA is measured via performance on elementary cognitive tasks (ECTs). ECTs assess basic information-processing ability, yet correlate moderately highly with GMA. Toward this end, we had male (n = 218) and female (n = 226) undergraduates complete the Wonderlic Personnel Test (WPT), and two ECTs: inspection time (IT) and reaction time (RT). The sex difference on the WPT was non-significant (d = .17), but small differences favoring males existed for IT (d = .34), RT (d = .26), the standard deviation of RT (d = .30), and an ECT factor score (d = .38). Unlike standardized IQ tests, ECTs may be a viable research tool to help clarify and illuminate the nature of sex differences on GMA.

Sex differences on the progressive matrices among adolescents: some data from Estonia Original Research Article

Personality and Individual Differences, Volume 36, Issue 6, April 2004, Pages 1249-1255

Richard Lynn, Juri Allik, Helle Pullmann, Kaia Laidra

Abstract

It has long been asserted that there are no sex differences on the Progressive Matrices. Contrary to this position, it has been contended by Lynn (1994, 1998) that there is a small difference favoring females from the age of approximately 9–14 years, and a difference favouring males from the age of 16 onwards, reaching approximately 2.4 IQ points among adults. Data to test these two theories are reported from a standardization of the Progressive Matrices on a sample of 2689 12–18 year olds in Estonia. The results confirm the Lynn theory and show a female advantage of 3.8 IQ points among 12–15 year olds and a male advantage of 1.6 IQ points among 16–18 year olds. Boys had a significantly larger standard deviation than girls. The results provide further confirmation that in early adolescence girls outperform boys on abstract (non-verbal) reasoning ability but that in later adolescence boys outperform girls.

Sex differences on the progressive matrices among 15–16 year olds: some data from South Africa Original Research Article

Personality and Individual Differences, Volume 33, Issue 4, September 2002, Pages 669-673

Richard Lynn

Abstract

It has been widely asserted that there is no sex difference in mean scores on the Progressive Matrices. This paper presents an alternative theory that a male advantage on the test begins to appear at the age of 15 years. This alternative theory is supported by data for the largest sample hitherto reported consisting of 3979 15–16 year olds in South Africa. In this sample males obtained a significantly higher mean equivalent to 2.35 IQ points among 15 year olds and to 4.65 IQ points among 16 year olds.

Personality and Individual Differences, Volume 36, Issue 4, March 2004, Pages 779-787

Richard Lynn, Eduardo Backhoff, Luis A. Contreras-Niño

Abstract

Normative data for sex differences on the Standard Progressive Matrices are presented for a sample of nine-hundred and twenty 7–10 year olds in Mexico. Factor analysis of the test showed the presence of factors identifiable as g, reasoning ability and visualisation. There was no statistically significant difference between boys and girls on the test, on g, or on reasoning. There was, however, a significant advantage for boys on the visualisation factor. There was also a non-significant trend for the boys’ advantage on the test to decline over the 4 years and to turn into an advantage for girls at age 10. This is consistent with the faster maturation of girls from the age of about 10 through 15 years.

Sex differences on the Dutch WAIS-III Original Research Article

Intelligence, Volume 34, Issue 3, May-June 2006, Pages 273-289

Sophie van der Sluis, Danielle Posthuma, Conor V. Dolan, Eco J.C. de Geus, Roberto Colom, Dorret I. Boomsma

Abstract

Summarizing, the present study showed that males and females do differ with respect to specific cognitive abilities, but that g cannot be viewed as the sour

Ich eröffne dazu mal einen eigenen Betrag zur Übersichtlichkeit der Disskussion.

Hormonelle, genetische und andere Faktoren für Geschlechterunterschiede

Weitere Studien, die verschiedene Faktoren für Geschlechterunterschiede untersuchen:

Both sexual orientation and sex-typical childhood behaviors, such as toy, playmate and activity preferences, show substantial sex differences, as well as substantial variability within each sex. In other species, behaviors that show sex differences are typically influenced by exposure to gonadal steroids, particularly testosterone and its metabolites, during early development (prenatally or neonatally). This article reviews the evidence regarding prenatal influences of gonadal steroids on human sexual orientation, as well as sex-typed childhood behaviors that predict subsequent sexual orientation. The evidence supports a role for prenatal testosterone exposure in the development of sex-typed interests in childhood, as well as in sexual orientation in later life, at least for some individuals. It appears, however, that other factors, in addition to hormones, play an important role in determining sexual orientation. These factors have not been well-characterized, but possibilities include direct genetic effects, and effects of maternal factors during pregnancy. Although a role for hormones during early development has been established, it also appears that there may be multiple pathways to a given sexual orientation outcome and some of these pathways may not involve hormones.

Research highlights

► Prenatal exposure to androgenic hormones influences human sexual orientation. ► Androgen dose predicts the likelihood of non-heterosexual orientation. ► Normal variability in testosterone prenatally predicts masculinity in childhood. ► Sexual orientation is predicted by masculinity/femininity of childhood behavior. ► Prenatal stress does not demasculinize boys, but may masculinize girls slightly.

Quelle: Prenatal endocrine influences on sexual orientation and on sexually differentiated childhood behavior

Die Studie passt zu den anderen Studien. Pränatales Testosteron beeinflusst die sexuelle Orientierung, dass Verhalten während der Kindheit etc. Da die Auswirkungen zu dem Testosteronspiegel im Mutterleib passen, sind sie mit der Gesellschaft nicht zu erklären.

Die Rolle der Gene beleuchtet auch eine weitere Studie:

Biological differences between men and women contribute to many sex-specific illnesses and disorders. Historically, it was argued that such differences were largely, if not exclusively, due to gonadal hormone secretions. However, emerging research has shown that some differences are mediated by mechanisms other than the action of these hormone secretions and in particular by products of genes located on the X and Y chromosomes, which we refer to as direct genetic effects. This paper reviews the evidence for direct genetic effects in behavioral and brain sex differences. We highlight the ‘four core genotypes’ model and sex differences in the midbrain dopaminergic system, specifically focusing on the role of Sry. We also discuss novel research being done on unique populations including people attracted to the same sex and people with a cross-gender identity. As science continues to advance our understanding of biological sex differences, a new field is emerging that is aimed at better addressing the needs of both sexes: gender-based biology and medicine. Ultimately, the study of the biological basis for sex differences will improve healthcare for both men and women.

Quelle: The genetics of sex differences in brain and behavior

Zu den „Four Core Genotypes“

The „four core genotypes“ (FCG) model comprises mice in which sex chromosome complement (XX vs. XY) is unrelated to the animal’s gonadal sex. The four genotypes are XX gonadal males or females, and XY gonadal males or females. The model allows one to measure (1) the differences in phenotypes caused by sex chromosome complement (XX vs. XY), (2) the differential effects of ovarian and testicular secretions, and (3) the interactive effects of (1) and (2). Thus, the FCG model provides new information regarding the origins of sex differences in phenotype that has not been available from studies that manipulate gonadal hormone levels in normal XY males and XX females. Studies of the FCG model have uncovered XX vs. XY differences in behaviors (aggression, parenting, habit formation, nociception, social interactions), gene expression (septal vasopressin), and susceptibility to disease (neural tube closure and autoimmune disease) not mediated by gonadal hormones. Some sex chromosome effects are mediated by sex differences in dose of X genes or their parental imprint. Future studies will identify the genes involved and their mechanisms of action.

Quelle: What does the „four core genotypes“ mouse model tell us about sex differences in the brain and other tissues?

Das scheint mir recht interessante Forschung zu sein. Mal sehen, was sie noch erbringt.

Klassische Fehlinterpretation von evolutionärer Psychologie

Die Feministin Kittywampus analysiert eine Stellungnahme aus Sicht der evolutionären Psychologie zur Weiner Affaire.

Ein verheirateter Abgeordneter hatte über das Netz geflirtet und dabei auch Fotos von sich verschickt.

Das Statement aus Sicht der evolutionären Psychologie:

From an evolutionary perspective, men are here to sow their seeds, so a sexual transgression here and there would make sense. They desire more sexual partners, and even lower their standards when it comes to one-night stands, studies have shown.

“The ultimate currency here is reproductive success and if there’s an opportunity for sex that is a goal that is worthy of such a risk,” Kruger said. …

This evolutionary urge, combined with modern technology that lets a person send off a note or photo to anyone in the ether, takes such risk-taking to a new level.

Ihre Kritik:

Here’s the kicker, though. Weiner’s chances of “sowing his seed” through social media were precisely nil. He took his bouncing bulge into the shower, from whence his seed could at best fertilize a female rat. (…)

It’s a basic tenet of standard evolutionary psychology that men’s sexual behavior is oriented toward fertilizing as many women as possible. That’s of course not synonymous with reproductive success, anyway, given that human offspring are uniquely vulnerable for an extraordinarily long time, and so “paternal investment” – sticking around to help raise the baby – actually amplifies a man’s chance of having his spawn live until adulthood.

But even if we ignore the importance of paternal investment in offspring, there’s a bigger gap in the ev psych explanation of Weinergate. Mainstream practitioners of ev psych systematically avoid theorizing about pleasure. It’s all about “reproductive success.” And yet, the quest for pleasure is by far the more parsimonious explanation for Weiner’s actions. What’s more, it even explains his partners’ actions! Weiner and his partners were looking to get off. They wanted the thrill of being wanted.

Damit macht sie deutlich, dass sie evolutionäre Psychologie nicht verstanden hat. Denn der Fortpflanzungserfolg, der als Ziel angegeben wird, ist ein theoretischer, der nur unter steinzeitlichen Gesichtspunkten interessant ist und nicht der tatsächliche Wunsch. Dieser kann darin bestehen, Vergnügen zu empfinden, aber der Grund, aus dem das Vergnügen empfunden wurde, war, dass es sich für den Mann gelohnt hat, das Risiko einzugehen, wenn es potentiell zu einem Kind führen kann. Was bei einem sexuellen Gespräch unter Mann und Frau in der Steinzeit durchaus wahrscheinlich war. Die Evolution kann das Internet natürlich nicht berücksichtigen und es ist insofern egal, dass das Verhalten heute nicht zu einer Befruchtung führen kann. Es muss nur damals die Chance auf eine solche erhöht haben, damit es sinnvoll war, den jeweiligen Menschen Lust an seinem Handeln fühlen zu lassen.

Plastizität des Gehirns und die Unterschiede zwischen den Geschlechtern

Gegen eine hormonelle biologische Ausgestaltung der Geschlechterunterschiede wird gerne die Plastizität des Gehirns ins Feld geführt.

Das Gehirn sie in der Lage, sich an jede Aufgabe anzupassen und in jedem Bereich gut zu werden. Die Unterschiede zwischen Männern und Frauen seien lediglich die Folge dieser Plastizität, weil das Gehirn durch die verschiedenen Erfahrungen anders ausgestaltet wird.

Dagegen würde ich diese Argumente anführen:

1. Die Unterschiedlichkeit der Behandlung ist nicht so groß, dass sie den Umfang der Unterschiede rechtfertigen würde

2. Wenn die Gehirne pränatal unterschiedlich ausgestaltet sind, dann wird es schwer, diesen Unterschied auszugleichen

2. Dass das Gehirn in einigen Bereichen flexibel ist, bedeutet nicht, dass es in allen Bereichen flexibel ist

4. Die unterschiedliche Behandlung kann gerade Folge der Unterschiede sein, nicht die Unterschiede die Folge der Behandlung

5. Studien zeigen, dass biologische Vorgänge Fähigkeiten unabhängig von der Sozialisation hervorrufen.

Zu Punkt 1:

Die Unterschiede zwischen Mann und Frau zeigen sich in Urwaldvölkern und in modernen westlichen Zivilisationen. Trotz Koedukation, Mathe- und Sprachunterricht für beide Geschlechter und diversen anderen Maßnahmen, die Geschlechter anzugleichen, bleiben aber die Geschlechtsunterschiede bestehen.

Zu Punkt 2.

Nehmen wir als Gedankenexperiment an, dass Männer mit räumlichen Denken +5 geboren werden und mit sprachlichen Fähigkeiten +1, und Frauen mit räumlichen Fähigkeiten +1 und mit sprachlichen Fähigkeiten +5. Es wäre zu erwarten, dass sich die Männer dann eher für Spielzeug interessieren, dass ihre räumlichen Fähigkeiten berücksichtigt und Frauen ein höheres Interesse für Sprache haben. Wenn nun das Baby schreit und sich das männliche Baby beruhigt, wenn man sein räumliches Denken stimuliert, er aber mit Beeinflussungen über die Sprache nicht zu beruhigen ist, dann ergibt dies möglicherweise eine weitere Stimmulation der räumlichen Fähigkeiten, aber sie wird schwer zu umgehen sein.

Dies ändert sich später nicht. Wenn er spielen will, dann werden ihm Bauklötze mehr Spass machen als seiner Puppe eine Geschichte zu erzählen. Damit mag man wieder seine räumlichen Fähigkeiten trainieren, aber auch das wird anderweitig nur gegen seinen Willen möglich sein.

Selbst wenn man die jeweilige andere Fähigkeit fördert, wird die gegen die Natur schwer sein: Nehmen wir an, dass man durch entsprechende Förderung das Mädchen zu einem Wert beim räumlichen Denken von +5 bekommt. Nach all dieser Quälerei werden die Jungs, die ebenfalls ihr räumliches Denken trainiert haben, weil ihnen das Spass macht (und nicht weil die Eltern es wollen) vielleicht schon einen Wert von +8 haben (wahrscheinlich sogar +10, weil man Sachen, die einem liegen, lieber lernt). Die Mädchen, die ihre sprachlichen Fähigkeiten in der Zeit verbessert haben, haben einen sprachlichen Wert von +8. Sie hingegen hat ihre sprachlichen Fähigkeiten zugunsten der räumlichen vernachlässigt und hat hier lediglich ihren Startwert von +5 Sie steht also mit einem eher unterdurchschnittlichen Wert in beiden Eigenschaften dar und es hat ihr keinen Spass gemacht (das gleiche gilt natürlich auch bei Jungs in anderen Eigenschaften). Sie konkurriert zudem innerhalb dieser verbesserten Eigenschaft beständig mit den Leuten, die bereits einen besseren Startwert hatten und gehört hier immer zur unteren Gruppe, weil sie diesen nicht aufholen kann. Denn Plastizität bedeutet ja nicht, dass sie schneller lernt und sie hat auch nicht mehr Zeit zur Verfügung als die anderen Kinder.

Eine Erziehung gegen die Eigenschaften produziert daher selten sehr gute Ergebnisse und dürfte eher unglücklich machen. (Natürlich gibt es auch Mädchen mit einem höheren Startwert in Fähigkeiten, die im Schnitt eher bei Jungs hoch sind, es handelt sich ja um Normalverteilungen mit unterschiedlichen Mittelwert, die sich überlappen. Diese wiederum werden dann die Erfahrung machen, dass ihnen für ihr Geschlecht untypische Sachen Spass machen und das sollte natürlich gefördert werden. Die Anzahl ist aber aufgrund der verschiedenen Mittelwerte deutlich geringer.

Zu Punkt 3.

Flexibilität in bestimmten Bereichen bedeutet nicht Flexibilität in allen Bereichen. Es kann bei sozialen Gruppentieren wie dem Mensch natürlich sinnvoll sein, diesem die Möglichkeit zu geben, in einer vorhandenen Lücke besondere Fähigkeiten zu erwerben, die ihn für die Gruppe wertvoll machen. Wer beispielsweise gut in Musik ist, der kann diese Fähigkeit natürlich mit Übung aufbauen und dadurch in der Gruppe seine Qualitäten darstellen. Allerdings ist es aus Sicht der Gene riskant, bestimmte Eigenschaften frei auszugestalten und nicht zumindest Grundwerte vorzugeben. Der Blank Slate bedeutet, dass möglicherweise ein ungünstiger Weg einegschlagen wird, der zu einer geringeren Verbreitung der Gene führt. Demnach sind Gene, die gewisse immer wieder gebrauchte Fähigkeiten vermitteln, günstig und verbreiten sich im Genpool. Da Männer und Frauen eine Arbeitsteilung haben und hatten und sie unterschiedliche Interessen und Risiken haben, ist es sinnvoll, diese Werte, die eine gewisse Sicherheit bieten, nach Geschlecht zu differenzieren. Auch Gene, die unterschiedliche Fähigkeiten für Männer und Frauen, angeapßt an deren Risiken und typische Tätigkeiten vorsehen, verbreiten sich aufgrund der Vorteile der Arbeitsteilung schnell im Genpool.

Es lohnt sich beispielsweise nicht, die sexuelle Identität plastisch zu machen und ein „Lernen“ zuzulassen. Die Gene, die dafür sorgen, dass diese Eigenschaft pränatal oder jedenfalls frühzeitig festgelegt werden, verbreiten sich recht offensichtlich im Genpool. Um so strikter eine Arbeitsteilung praktiziert wird um so deutlicher muss auch das Gehirn in diesen Bereichen, die der Arbeitsteilung unterliegen unplastisch sein. Ein Mann, der schlecht in der Jagd ist, dürfte erhebliche Nachteile gehabt haben. Eine Frau, die schlecht im sprachlichen Bereich ist, konnte sich schlechter in eine neue Gruppe mit anderer Sprache einbringen etc. Da sie das vielleicht auch erst mit 15 oder 16 machen mußte, wenn sie mit einem Mann zu dessen Stamm wechselt hilft ihr in diesem Bereich eine Plastizität wenig. Frauen, die von vorneherein besser im Lernen von Sprachen waren, auch wenn dies nicht besonders stimmuliert wurde, hatten demnach einen Vorteil und ihre Gene reicherten sich im Genpool an. Da die Frauen schwächer waren, waren sie eher darauf angewiesen, soziale Zeichen wahrzunehmen und Gefühle deuten zu können. Dies dürfte auch bei der Babybetreuung hilfreich gewesen sein, die bei Säugetieren in prähistorischen Zeiten schlecht an den Mann abgegeben werden konnte. Auch hier waren Frauen mit einer besseren Empathie, einer geringen Aggressivität etc im Vorteil und Frauen, deren Gene dies vom Start an berücksichtigen und wenig Plastizität in diesem Bereich zulassen, konnten ihre Gene im Genpool anreichern. Wenn es von Männern erwartet wurde, dass sie sich zu Jagdzwecken weiter von der Gruppe entfernen als Frauen und zudem der Weg, etwa bei der Verfolgung eines Tieres, verschlungener ist, dann bringt es mehr, ein besseres räumliches Denken festzuschreiben als zu risikeren, dass er dies nicht erlernt oder beim Erlernen verloren geht. Auch Gene, die eine bessere Orientierung für Männer bewirken, reichern sich schnell im Genpool an.

Es gibt aber Fähigkeiten, die nicht so zentral für die Aufgaben sind, die klassischerweise den Geschlechtern zufallen. in diesen ist eine Plastizität zur Besetzung der jeweiligen Nischen sinnvoll.

Zu Punkt 4.

Hier habe ich oben bereits einiges angeführt. Wir finden sie in vielen anderen Bereichen und akzeptieren sie dort, in Geschlechterfragen wird dies aber als political uncorrect angesehen. Wer ein feines Gehör hat, der wird sich eher für Musik interessieren. Natürlich wird er sein Gehör auch weiter ausbilden, aber wir akzeptieren eine Begabung dafür. Wer mit beiden Händen einen verschiedenen Rhytmus schlagen kann, der wird eher Schlagzeuger werden als jemand, der dies nicht kann. Auch das wird meist als biologische Eigenschaft akzeptiert. Es verwundert uns auch nicht, wenn der Sohn eines Spitzenklavierspielers und einer Spitzenklavierspielerin ebenfalls eine gute Fingerfertigkeit aufweist (auch wenn dies nicht der Fall sein muss).Wir akzeptieren, dass er deswegen ebenfalls Klavierspieler werden will, dies aber nicht macht, wenn er die Fingerfertigkeit, das feine Gehör, das Taktgefühl aber nicht als Eigenschaft geerbt hat. Wir würden es dann als einen Fehler der Eltern ansehen, wenn sie ihn trotzdem dazu zwingen, professioneller Klavierspieler zu werden und solange zu üben, bis er seinen Nachteil ausgeglichen hat.

Es erscheint uns auch normal, dass man einen sehr jähzornigen Menschen anders behandlelt als einen sehr geduldigen Menschen und wenige würden sagen, dass er so jähzornig geworden ist, weil die Leute alle vorsichtiger mit ihm umgegangen sind.

Zu Punkt 5

Auf die diversen Studien bin ich ja bereits des häufigeren eingegangen. Sie zeigen, dass sich Menschen trotz der anderen Sozialisation über diese aus biologischen Gründen hinwegsetzen. Die meisten dürften unter „pränatales Testosteron erzeugt die Geschlechter“ zu finden sein.

Frauen beachten an ihren fruchtbaren Tagen Status mehr

Noch eine Verhaltensänderung während des Zyklus:

In line with evolutionary principles of reproduction and mate selection, the current research shows that women’s attention to status cues fluctuates across their menstrual cycle. Specifically, we show that women pay more attention to status products in a visual display around ovulation than in other phases of their menstrual cycle. Pill use eliminates these cycle phase effects. The results are discussed in relation to research on female mating goals and conspicuous consumption.

Source: „Would male conspicuous consumption capture the female eye? Menstrual cycle effects on women’s attention to status products“ from Journal of Experimental Social Psychology

Das sie gerade dann, wenn sie fruchtbar sind, mehr auf Statussymbole achten, passt in der Tat gut in das Schema. Denn gerade zu diesem Zeitpunkt wäre ein hoher Status bei der Partnerwahl ja wichtig. Da es innerhalb des Zyklus schwankt ist auch davon auszugehen, dass es nicht an gesellschaftlichen Umständen liegt. Es macht auch deutlich, dass Statusbetrachtungen biologisch eingespeichert sein können.