well here goes....its called genetic attraction....
People tend to select mates that are like themselves, which is known as
assortative mating. This holds both for physical appearances and mental traits. People commonly rank faces similar to their own as more attractive, trustworthy, etc. than average.
[3] However, Bereczkei (2004) attributes this in part to childhood
imprinting on the opposite-sex parent. As for mental traits, one study found a
correlation of 0.403 between husbands and wives, with husbands averaging about 2 IQ points higher. The study also reported a correlation of 0.233 for
extraversion and 0.235 for inconsistency (using
Eysenck's Personality Inventory). A review of many previous studies found these numbers to be quite common.
[4]
Heredity produces substantial physical and mental similarity between close relatives. Shared interests and personality traits are commonly considered desirable in a mate. The
heritability of these qualities is a matter of
debate but estimates are that
IQ is about 80% heritable, and the
big five personality factors are about 50% heritable. This data is for adults in Western countries.
[5]
For the above reasons, genetic sexual attraction is presumed to occur as a consequence of genetic relatives meeting as adults, typically as a consequence of adoption. Although this is a rare consequence of adoptive reunions, the large number of adoptive reunions in recent years means that a larger number of people are affected.
[6] If a sexual relationship is entered, it is known as
incest.
GSA is rare between people raised together in early childhood due to a
reverse sexual imprinting known as the
Westermarck effect, which desensitizes them to later close sexual attraction. It is hypothesized that this effect
evolved to prevent
inbreeding.
[7][8]
Genetic sexual attraction - Wikipedia, the free encyclopedia
now before yall go all over me...you ask why and what would be a rational for incest....well there ya go....
and be aware i have no siblings...the whole concept of siblings is beyond me.....seems this happens mostly with kids united with parents at adulthood.....now that is just nasty
