Nov 06 2009
Testosterone and the Reading of Finger Lengths
My bad. In a recent post, Unconscious Influences and the Faces of Homosexual and Aggressive Behavior, I wrote -
One replicated study I recall discovered that a greater difference in the length of pointer and middle fingers in men and women correlates with higher testosterone levels. And higher testosterone levels are associated with a greater propensity for aggressive behavior.
Seems I remembered wrong. The fingers in question are the fourth and the second fingers (pointer and ring). An article I read yesterday set my knowledge straight and advanced it. In Hormone that affects finger length key to social behavior I read of these three clues to the potential influence of hormones on primate behavior:
1. Finger ratios do not change very much after birth and appear to tell us something about how very early androgens affect adult behaviour, particularly behaviour linked to mating and reproduction.
2. The team found that Old World monkeys, such as baboons and rhesus macaques, have a longer fourth finger in comparison to the second finger, which suggests that they have been exposed to high levels of prenatal androgens. These species tend to be highly competitive and promiscuous, which suggests that exposure to a lot of androgens before birth could be linked to the expression of this behaviour.
3. Lower androgen levels could help explain why Great Apes show high levels of male cooperation and tolerance.
From the research into testosterone and hand measurements, I think I would be justified in proposing that, to divine the general traits of a species, “reading” the relative length of their fingers would be more productive than reading their palms.
Interesting stuff. I hope in the future more studies will be conducted on the influence of both “male” and “female” hormones on human behavior.
[...] Update: I was off on which fingers provide a clue to prenatal exposure to testostorone. It is the ring and index finger. For more on this, see my newer post, Testosterone and the Reading of Finger Lengths. [...]
It is culture that drives genetic changes, NOT genetic changes that drive cultural evolution!
Of Primate Fingers And Nostril
Quotes from “Hormone That Affects Finger Length Key To Social Behavior”
http://www.sciencedaily.com/releases/2009/11/091104101553.htm
1) “Research at the universities of Liverpool and Oxford into the finger length of primate species has revealed that cooperative behavior is linked to exposure to hormone levels in the womb.”
* Unbelievable. A unique and novel revelation. What will they reveal next? They might next reveal that the origin of social cooperative behaviour is in cooperative behaviour of cells in a multicelled organism, or even earlier in a cooperative behaviour of monocell organisms in their hormoned communities (cultures), or even earlier in cooperative behaviour of genes in a genome, or – Heaven Forfend – even earlier in cooperative behaviour of molecules, and even earlier of atoms, yes, atoms, to form self-replicating energy constraining genes on Earth to prevent some of it’s sun-star energy from serving as fuel for the expansion of galactic clusters…. You mean that everything, yes everything, goes back to the Big Bang? Unbelievable! Why, this turns out to having revealed that everything in the universe, on Earth and life are all evolving intertwiningly! Unbelievable!
2) “Research from finger ratios may help us understand more clearly the development of human sociality and its evolutionary origins.”
* I suggest that research of evolution of the coordinated structures and dimensions of human’s nose-picking finger and nostril may help us understand more clearly the development of human profundity and its evolutionary origins.
Dov Henis
(Comments From The 22nd Century)
Updated Life’s Manifest May 2009
http://www.the-scientist.com/community/posts/list/140/122.page#2321
Implications Of E=Total[m(1 + D)]
http://www.the-scientist.com/community/posts/list/180/122.page#3108