September 6, 2011
For quite a few years researchers have assumed that finger length development and the 2D:4D digit ratio is directed by sex hormones. Nevertheless, until now direct experimental evidence was lacking. However, researchers from Florida have reported an important discovery. They discovered via a study of the limb buds in mice – which are known for having a digit length ratio similar to humans – that human fingers are likely to have likewise sex hormone receptors as seen in the paws of mice.
A few comments made by researchers Martin Cohn (one of the researchers from Florida) and ‘finger professor’ John Manning:
“The discovery that growth of the developing digits is controlled directly by androgen and estrogen receptor activity confirms that finger proportions are a lifelong signature of our early hormonal milieu,” Cohn said.
“I’ve been struggling to understand this trait since 1998,”said John T. Manning, Ph.D., a professor at Swansea University in the United Kingdom, who was not involved in the current research.“”When I read this study, I thought, thank goodness, we’ve attracted the attention of a developmental biologist with all the sophisticated techniques of molecular genetics and biology.” “When Zheng and Cohn blocked testosterone receptors, they got a female digit ratio,” Manning said. “I find this completely convincing and very useful,” Manning said.“We can now be more focused in our examination of the links between digit ratio and sex-dependent behaviors, diseases of the immune system, cardiovascular disorders and a number of cancers.” “He suggested that the 2D:4D ratio would be an interesting question, and I have to admit to being skeptical,” Cohn said. “When he came back with the initial results, I was blown away. We looked at each others hands, then got busy planning the next experiment.”
The new discovery provides a genetic explanation for a raft of studies that link finger proportions with traits ranging from sperm counts, aggression, musical ability, sexual orientation and sports prowess, to health problems such as autism, depression, heart attack and breast cancer.
The report about the new study appears in this week’s Proceedings of the National Academy of Sciences.
An overview of some key-reports about finger ratios:
July 5, 2011
JULY 4, 2011 – Finally… the long waited proof is now available: Korean researchers from the In Ho Choi of Gacheon University Gil Hospital, have pointed out that the popular ‘digit ratio‘ does correlate with penile length!
Finger professor John T. Manning had already pointed out in his second book ‘The Finger Book‘ (2008) that a Greek study in the Naval and Veteran’s Hospital of Athens (2002) had pointed out that the length of the index finger correlates with the length, glans & volume of the penis. Manning commented (in ‘The Finger Book’):
“Spyropoulos and his collegues did not measure the remaining fingers, so we cannot be sure of their relationship to penis length. My guess is that they would have found the ring finger the strongest predictor, and that long ring fingers in relation to index fingers would be associated with longer penises.”
The new Korean study shows that John Manning – the ‘finger professor’ – was right… again!
The researchers from Korea found that the ratio between the second and fourth digits on men’s right hand correlate to the length of his flaccid and stretched penis. A lower index-to-ring finger length ratio indicates a longer (stretched) penis.
NOTICE: The table below is taken from the scientific article; it e.g. illustrates that likewise results were found for body length and penis length – for the ‘flaccid condition’ the result for body length were slightly higher than for the 2D:4D digit ratio, but in the ‘stretched condition’ finger length ratio was a better predictor for penis length!
The key to this relationship may lie in the womb, a team member added:
“During the fetal period, high concentrations of testosterone lead to high testicular activity, resulting in a lower digit ratio, in the present study, patients with a lower digit ratio tended to have a longer stretched penile length.”
The researchers also added that the length of the stretched and flaccid penis does show “a strong correlation” with an erect penile length.
The Korean report was published on july 4 in the Asian Journal of Andrology, and the scientific article is available at Nature.com.
How can we understand this correlation between finger lenght and penis length?
Let’s take a look at the hands of one of the biggest ‘stars’ in the adult industry today: Ron Jeremy. Jeremy is today known as the ‘best performing’ male adult star ever, he is e.g. listed in the Guinness Book of World Records for “Most Appearances in Adult Films”, and he is noted for his 9.75-inch (~24.75 cm) penis (self-reported according Wikipedia).
How about his hands? His handprints are display at the entrence of Hustler’s Hollywood, at the ‘Porn Stars Walk of Fame’ in West Hollywood, California – see the picture below. His 2D:4D digit ratio is estimated at 0.85… which is exceptionally low for a caucasian male!
MORE FAMOUS HANDS AVAILABLE AT:
‘Hands of fame’ – The hands of 93 celebrities & famous people!
June 7, 2011
Amyotrophic lateral sclerosis (abbreviated ALS) is a form of motor neuron disease caused by the degeneration of neurons in the brain. The condition is often called Lou Gehrig’s disease in North America, after the famous New York Yankees baseball player who was diagnosed with the disease in 1939. The disorder is characterized by rapidly progressive weakness, muscle atrophy and fasciculations, spasticity, dysarthria, dysphagia, and respiratory compromise. ALS is a fatal disease with most affected patients dying of respiratory compromise and pneumonia after 2 to 3 years; although occasional individuals have a more indolent course and survive for many years. The cause is usually unknown, but a new Canadian finger length study suggests that the onset of ALS may even be determined before birth!
For patients without a family history of the disease, which includes ~95% of cases, there is no known cause for ALS – though environmental causative factors have been indentified.
Interestingly, earlier this year a new Canadian finger length study suggests that the onset of ALS may partly be established even before birth!
The Canadian researchers report:
“A biomarker that has generated considerable interest is digit ratio, the ratio of the second (index) finger to the fourth (ring) finger, 2D:4D. Men have a longer fourth digit relative to the second digit than do women, and the ratio is lower in boys and men than in girls and women. 1 A reduced 2D:4D ratio is assumed to indicate reduced prenatal androgen exposure or sensitivity and high prenatal testosterone levels.”
PEOPLE WITH A LONGER RING FINGER ARE NOT ‘AT RISK’!
The researchers hasten to explain, however, that this does not mean people with long ring fingers will develop the disease — or even that they are at higher risk for it.
“We have not done a study that shows the risk of subsequently getting ALS in people with long ring fingers,” cautioned lead researcher Ammar Al-Chalabi, a professor of neurology and complex disease genetics and director of King’s MND Care and Research Center at King’s College London.
What the study does find, Al-Chalabi said, is that “people with ALS tend to have more ‘male’ hands in that the ring finger is relatively longer than the index finger – something that is a tendency in men.”
“We already know that ALS is commoner in men, but this might suggest that the reason is something to do with the balance of hormones we are exposed to in the womb, because finger length seems to be determined in part by the amount of male hormone a developing baby is exposed to,” he added.
May 24, 2011
Various studies have shown that babies exposed to higher levels of testosterone when developing in the uterus have longer ring fingers as adults, and higher levels of oestrogen typically result in longer pointer fingers. However, testosterone & oestrogen levels also affect the rest of the body, including a person’s physical appearance. The ratio between the length of the index and ring fingers has been found to be a good indication for a variety of social and economic factors, thought to be directly or indirectly related to the effects of the prenatal testosterone. These photographs are part of a study on beauty and sexual attraction.
In 2010 a Meta-analysis studyby researchers from the University of Ontario, Penn State, and the Centre for Addiction and Mental Health found that the second to fourth finger length ratio (2D:4D) serves as an indicator of sexual orientation. The study included 1.618 heterosexual men, 1.693 heterosexual women, 1.503 gay men, and 1.014 lesbians.
In addition to identifying the normative heterosexual sex difference in 2D:4D for both hands, the researchers found that heterosexual women had higher (more feminine) left- and right-hand 2D:4D than did lesbians. However… the researchers found NO difference between heterosexual and gay men (though moderator analyses by the researchers suggested that ethnicity explained some between-studies variation in men).
MORE FINGER & DIGIT RATIO REPORTS ARE AVAILABLE AT:
Since the classic Roman time the ring finger has been known to be associated with the wearing of rings in married men and women. The literature indicates that this early belief appears to origin in the idea that a nerve, vein or artery runs directly from the 4th digit to the heart, and therefore it became judged to be the seat of the emotions. Unfortunately medical science today appears not able to present any anatomical evidence that confirms this idea. Nevertheless, there are various other interesting explanations which describe how the ring finger became associated with marriage!
Despite the missing of anatomical evidence for a connection with the heart, there is alternative evidence which suggest that wearing a ring on the ring finger can be associated with the ‘control’ of brute emotions.
CASANOVA HAD THE LONG RING FINGER:
Anecdotal evidence is found in the memoirs of Giacomo Casanova from Venice, who became known as one of the most famous ‘womanisers’ of all times. Casanova’s life as an adventurous writer took him across Europe, and in his memoirs about his stay in Spain we learn of the relative length of his fingers. Casanova described a dispute with the painter Anton Raphael Mengs about the ‘human condition’ of the ratio between the index finger and the ring finger. While Menge was claiming that his longer index finger was the correct human condition, Casanova claimed that his long finger was ”like that of all the children descended from Adam’.
But Casanova was not aware that his claim was basically only true for men only!
COMMITMENT WITH MARRIAGE:
Professor John Manning from the UK presented two books devoted to the ‘2D:4D digit ratio’. In his first book, Manning presented some evidence that the wearing of rings in married women can be understood as an act of ‘advertising’ their commitment to their marriage.
Additionally, the study also demonstrated that a considerable lower percentage of the married men (29%) was wearing a ring on their ring finger – while the percentage was considerably higher for the married women (71%).
FINGER LENGTH REPRESENTS A PRENATAL MARKER:
Today especially the length of the ring finger became known as a prenatal marker for masculinity, and in all regions of the world studies have confirmed that in males the absolute length of the ring finger is usually longer than the absolute length of the index finger. And some studies have pointed out that the sexual dimorphism in finger measures is even more strongly expressed in the distal extent of fingertips than in the length of fingers.
In his second book ‘The Finger book’ Prof. John Manning describes a few references to scientific studies dating back to the 19th and early 20 century:
“The ‘Casanova pattern’ in the fingers is considered by some to be the mark of an ugly hand – an atavistic hand recalling brute instincts and behaviours, modelling the forms of the fingers of our monkey relatives. Thus the ‘beast’ in us is represented by the ring finger while the ‘beauty’ resides in the index finger. This notion has led to suggestions that the femininised ‘Mengs pattern’ is of a purer type, a hand which signifies emancipation from our primate ancestry. … Science, however, has been slow to identify the importance of such connections. That there is a sex difference in the relative length of men’s and women’s fing and index fingers has been known for more than a century. Compared to sex differences arising at puberty the finger ratio is modest in its size and visibility, and it has been neglegted.”
These considerations provide an explanation about why the 4th finger became known as the ‘ring finger’. The ringfinger became also known as the 4th finger or the annulus (digitus annularis).
The following books about fingers are highly recommended to read much more about fingers (presenting various elements that can be described as ‘building stones’ in Mult-Perspective Palm Reading):
• Fingerology (2010), authors: Hillary J. Kener & Michael Zeide
• The Finger Book (2008), author: John T. Manning
• Digit Ratio (2002), author: John T. Manning
Last year British researchers reported new confirmative findings for a link between index finger length (relative to ring finger length) and the risk of developing prostate cancer. Men featured with a longer index finger than ring finger, appear to have a 33% higher chance for not developing prostate cancer.
Often such studies are qualified by non-experts as “nonsense” – initially because of the association with classical palmistry. Usually a main argument of concern is the seize of the studied sample: many ‘2D:4D digit ratio’ studies have been focused relatively small samples, and usually with the statistics were simly not strong enough to be applied to individuals. But those arguments can not be used to the describe the new British study!
The new British research involves a study where the hands of 1,524 prostate cancer patients were examined, which were compared with a control group of 3,044 men.
It can also be noted that Professor John Manning described in his second book ‘The Finger Book‘ with great details the suspected link between the ‘2D:4D digit ratio’ and prostate cancer – a complex theory about of role glutamine chains in the sensitivity of hormone receptors, which in their turn play a role in the activation of testosterone in the body:
“…The various forms of the androgen receptor have important consequences for our health and behaviour. For example, African-American men have shorter glutamine chains (high sensitivity to testosterone) than white men. Short glutamine chains are associated with an increased susceptibility to prostate cancer, and this may in part explain why the incidence of prostate cancer is higher in African-Americans than in white Americans. …”
In short, there seems to exist a triangular relationship between: 1) the high percentage of prostate cancer in Americans with African ancestry, 2) the length of the glutamine chains, and 3) the length ratio between index finger and ring finger.
The importance of the new British study can be recognized in the fact the use of preventive screening for prostate cancer – which is anno 2010 usually done through the use of a blood test – is still an object of confusion. Simply because the benefits of the screening devices are still very unclear. Meanwhile it is a fact that prostate cancer is known as the No. 1 cause of death from cancer in men (see picture below).
Therfore finger length assessment can become a new tool in prostate cancer screeing!
The British researchers therefore are speculating about how to add a practical application of their finger length study to the traditional methods of prostate cancer prevention screening!
November 5, 2010
Researchers from England & Canada presented earlier this week brand new evidence that the neanderthals’ life was much more dominated by competition & promiscuity than our lifes today! Maybe more surprizing is the method that the researchers used to acquire their new findings: finger length ratio measurements!
The study, published in the Proceedings of the Royal Society B, draws upon a famous and controversial indicator of social behavior: the comparative length of the index finger and the ring finger, also known as the 2D:4D finger ratio. If the ring finger is longer than the index finger, that’s supposed to be correlated with higher prenatal exposure to androgens — resulting in a higher proclivity for aggressiveness and promiscuity.
A few numbers from the results:
• Modern humans averaged a 0.957 index-to-ring finger ratio, and were considered to be on the line between a “pair-bonded,” or monogamous, species and a middle-of-the-road species.
• Chimps, gorillas and orangutans had index-to-ring ratios in the 0.90 to 0.92 range, and were classified as “non-pair-bonded,” or promiscuous.
• An early modern human from Israel’s Qafzeh Cave, thought to be about 95,000 years old, had an index-to-ring ratio of 0.935. Based on that statistic, the researchers surmised this individual would be more promiscuous than modern humans.
• The finger bones from five Neanderthals yielded a 0.928 ratio, associated with even greater competitiveness and promiscuity. Ardipithecus’ bones took it up another notch, to 0.899. Two even older primate ancestors, Hispanopithecus and Pierolapithecus, had ratios of 0.848 and 0.908, which means they would have been tough to live with as well.
• On the other end of the spectrum, the monogamous gibbons had a 1.009 ratio … and the australopith sample came in with a ratio higher than that of modern-day humans (0.979). The implication, then, is that australopiths were monogamous.
Scientists, in collaboration with researchers at the universities of Southampton and Calgary, used finger ratios from fossilised skeletal remains of early apes and extinct hominins, as indicators of the levels of exposure species had to prenatal androgens – a group of hormones that is important in the development of masculine characteristics such as aggression and promiscuity.
It is thought that androgens, such as testosterone, affect finger length during development in the womb. High levels of the hormones increase the length of the fourth finger in comparison to the second finger, resulting in a low index to ring finger ratio (2D:4D digit ratio). Researchers analysed the fossil finger bone ratios of Neanderthals and early apes, as well as hominins, Ardipithecus ramidus and Australopithecus afarensis, to further understanding of their social behaviour.
The team found that the fossil finger ratios of Neanderthals, and early members of the human species, were lower than most living humans, which suggests that they had been exposed to high levels of prenatal androgens. This indicates that early humans were likely to be more competitive and promiscuous than people today.
The results also suggest that early hominin, Australopithecus – dating from approximately three to four million years ago – was likely to be monogamous, whereas the earlier Ardipithecus appears to have been highly promiscuous and more similar to living great apes. The research suggests that more fossils are needed to fully understand the social behaviour of these two groups.
Dr Susanne Shultz, from the Institute of Cognitive and Evolutionary Anthropology at the University of Oxford describes:
“Social behaviours are notoriously difficult to identify in the fossil record. Developing novel approaches, such as finger ratios, can help inform the current debate surrounding the social systems of the earliest human ancestors.”
And Dr Emma Nelson, an archaeologist from the University of Liverpool, argues that comparing the finger-length ratios of extinct and present-day species is a valid technique for making an indirect assessment of our long-gone ancestors’ social behavior. She said:
“It is believed that prenatal androgens (male sex hormones) affect the genes responsible for the development of the fingers, toes and the reproductive system. We have recently shown that promiscuous primate species have low index to ring finger ratios, while monogamous species have high ratios.”
“We used this information to estimate the social behaviour of extinct apes and hominins. Although the fossil record is limited for this period, and more fossils are needed to confirm our findings, this method could prove to be an exciting new way of understanding how our social behaviour has evolved.
Can finger length predict infidelity?
[tweetmeme source=”handresearch” only_single=false] Earlier this year Dr. Phil and his panel of medical experts discussed the new science behind a cheater’s brain and what can be done if your loved one is at a higher risk. Author of Change Your Brain, Change Your Body, Dr. Daniel Amen, author of Insatiable Wives, clinical psychologist Dr. David Ley, Claremont University’s Dr. Paul Zak and author of The Male Brain, neuro-psychiatrist Dr. Louann Brizendine explain how you can discern a man’s risk for infidelity and the treatment options to lower his risk. Studies have indicated that the ‘Casanova-type’ finger ratio (low 2d:4d) is often seen in polyandry + polygyny populations, and …men who cheat!
Dr.Phil.com presents a 4 item list of physiological indicators that your han is at a higher risk for cheating:
Length of ring finger compared to pointer finger: The length of a man’s ring finger is linked to testosterone in utero and during puberty. A longer ring finger means more testosterone, and the increased likelihood of a greater number of sex partners and a higher risk of cheating.
- Facial symmetry and size of jaw: If one side of a man’s face matches the other side, is symmetrical, the more it is an indicator to women that that man has high genetic value. Men whose faces are more [symmetrical] are more likely to have more partners because more women want to have their children.
- Size of penis: If a male is well-endowed, that means more testosterone and a higher risk of cheating.
- Brain injuries: Men with a history of engaging in impact sports like football or martial arts, or men who’ve had a history of concussions are at a higher risk. Also, men with disorders like ADD or bipolar disorder have low pre-frontal cortex activity or hyper-frontal activity, which could mean less ability to stop impulsive behaviors, like cheating.
So, how surprising is it really that Casanova had as well the long ring finger !?
SUGGESTION FOR FURTHER READING:
• BBC Test: finger length & sex I.D.!
• Finger length & Cupid’s science!
• The science of gaydar: finger length & sexual preference!
• What they say about men with long ring fingers!
[tweetmeme source=”handresearch” only_single=false] A new soccer documentary “How To Win The FIFA World Cup” (Sony Pictures Television International, 2010) predicts that from a scientific point of view, Brazil is most likely to become the FIFA World Cup winner in 2010. How come that Brazil is usually performing so well in football? Finger length research by British ‘finger professor’ John Manning provides a clue!
WHO WILL WIN THE 2010 FIFIA WORLD CUP?
Bernard Krikke + fellow researchers from the University of Groningen analysed 28,400 minutes of football matches including over 250,000 moment from the fields during World Cup games (from 1990 to 2006). According their DMA-analysis (based on: Defense Midfield Attack) Brazil is most likely to win the 2010 tournament, France might become the runner-up, and The Netherlands + Germany are most likely to play for Bronze.
The full documentary can be streamed from: RTL’s ‘Wie wint the FIFA WK voetbal’
Ronaldo (right hand digit ratio estimate: 0.93) was the Golden ball winner of the FIFA World Cup 1998.
FINGER LENGTH & FOOTBALL PLAYERS IN BRAZIL!
Brazil’s footballing prowess may have more to do with the players’ finger lengths than their training schedule or their ‘hunger’ to succeed, say scientist John Manning from the University of Liverpool.
At the 12th Commonwealth International Sport Conference, held in Manchester in the lead-up to the recent Commonwealth Games, Dr John Manning reported on studies suggesting that one simple physical feature offers an accurate means of predicting future footballing ability. It kicks in in the womb and can be seen from birth.
In collaboration with colleagues Dr Rogan Taylor and Dr Peter Bundred, John Manning measured the digits of amateur footballers from UK local leagues and professional footballers from the Brazilian first division club Internacional of Porto Alegre. He found a low ratio between the index finger and the ring finger in all the footballers, but the ratio was much lower in the professional players.
Romário (right hand digit ratio estimate: 0.93) was the Golden ball winner of the FIFA World Cup 1994.
Manning explains in his second book ‘The Finger Book‘ (2008):
“In collaboration with Rogan Taylor and senior coach João Paulo Medina, I was recently fortunate enough to measure the finger ratios of a Brazilian First Division side, Sport Club International of Porto Alegra.”
“The hands of ninety-nine players were photocopied, of whom thirty-three were members of the senior playing staff. This group of players had an average left-hand finger ratio of 0.93, more masculined than English football’s ‘League Legends’. The first-team squad consisted of twenty players with an even lower average finger ratio of 0.92, and thirteen reserves with a mean ratio of 0.96. Considering the first-team squad, six players had astonishingly low ratios of below 0.90. This group included a forward with a ratio of 0.885, who was subsequently transferred to Barcelona for a fee reported to be in excess of $12 million.”
The biggest unanswered question is… who has the Brazilian football player that was transfered to Barcelona for $12M?
Pelé (right hand digit ratio estimate: 0.94) was the Golden ball winner of the FIFA World Cup 1970.
A final impressive illustration of Brazil’s football ability:
Brazil is widely known as the only country that was able to win the Word Cup five times. But even more impressive… in the history of football only 12 players were able to win the ‘Golden Ball’ when the tournament was not played in the home country of the player. Six of those players were Brazilians! The names are: Leonidas (1938), Didi (1958), Garrincha (1962), Pelé (1970), Romário (1994) & Ronaldo (1998) – the list of non-brazilian names is also impressive: Ferenc Puskás (1954), Johan Cruijff (1974), Paolo Rossi (1982), Diego Maradona (1986), Oliver Kahn (2002) & Zinedine Zidane (2006).
Based on track-record AND finger length: in the Brazilian 2010 football squad are Kaká, Robinho and Luis Fabiano the most important nominees for winning the ‘FIFA World Cup Golden Ball 2010’ in South-Africa.
SUGGESTIONS FOR FURTHER READING:
The 2010 football squad from Brazil.