David Becker

Chemnitz University of Technology · Department of Psychology

Hello dear colleagues,

I'm not an trained expert in this field but very interested in human prehistoric migration and population genetics. For purposes of understanding, I created a phylogenetic tree of Y-chromosomal haplogroups by using data from ISOGG.org, and additionally collected data about time and location of the MRCAs from available literature.

I would delighted if someone with more expertise could take a look on this tree and give me some comments, notes about errors etc.. It has only a rough resulution down to second degree subgroups. Therefore, this review would not take much time to complete.

If someone wants to do that, I will sending her or him a pdf of this tree.

Best regards, David Becker.

Hello, I am looking for sources about the ratio of mono- and dizygotic births on the cross-national level. I found the following numbers in an older book about human genetic (Vogel & Motulsky, 1986, p.207): 

Spain (1951-1953): 59DZ per 10,000births / 32MZ per 10,000births

Portugal (1955-1956): 56 / 36

France (1946-1951): 71 / 37

Austria (1952-1956): 75 / 34

Switzerland (1943-1948): 81 / 36

(Western)Germany (1950-1955): 82 / 33

Sweden (1946-1955): 86 / 32

Italy (1949-1955): 86 / 37

England and Wales (1946-1955): 89 / 36

U.S.A. whites (?): 67 / 39

U.S.A. blacks (1905-1959): 110 / 39

U.S.A. Chinese (?): 22 / 48

U.S.A. Japanese (?): 21 / 46

Japanese (1955-1962): 24 / 40

I'm looking for other nations and more recent time periodes but only found numbers about twin-births in general. Does anyone has records on the subject or know where I could obtain these data? Cross-national level would be prefered but sub-populations can also be helpful.

Thanks in advance, David.  

Referece: Vogel, F. & Motulsky, A. G. (1986). Human Genetics - Problems and Approaches. Second, Completely Revised Edition. Berlin, Heidelberg: Springer Verlag, p.207.

I'm looking for studies about historical changes in cultural concepts and cultural (self)identification. Claims are a global perspective across long historical epochs from Antiquity through the Middle Ages up to modern times. Also good monographs would be useful.

Thanks in advance, David.

Hello,

Does anyone know a good source of global re- and transit-migration rates per nation? A list of >150 nations would be prefered.

Or a suitable method to calculation such a variable by using population data like: 

- Migration-rates

- Migrant stock

- Annual rate of change of the migrant stock

- etc.?

Thank you, David Becker.

Hello,

I am looking for sources about (un)detected associations between attractiveness and teaching quality/evaluation results, at universities as well as schools or other educational institutions. Is there an influence of teacher’s attractiveness on his or her ability to mediate teaching stuff? What is the impact of teacher’s attractiveness on attention or visitors quote of students?

Especially studies about facial attractiveness, but also posture and movement in lectures are required. In addition, measurement methods of attractiveness would not be bad.

Thanks in advance, David.

Dear colleagues,

I want to calculate genetic distances between human populations by using frequencies of Y-DNA-haplogroups, to investigate genetic/evolutionary causes for differences in polygenetic psychological traits e.g. depression, ASB and cognitive abilities.

HG-frequencies are collected and compared in a meta-analysis. Now I found many analogical formulas to calculate genetic distances in literature (e.g. Cavalli-Sforze chord distance; Cavalli-Sforze and Edwards chord distance; Nei distance; Bhattacharyya and Nei distance; Rogers distance; Reynolds distance etc.) and I want to ask, which formula is most suitable for my purposes?

Thanks in advance, David.