Digit Ratio Research in Animals
- Dennis McFadden and collaborators have demonstrated sexual dimorphism in hind limb digit ratio in a number of great apes, including gorillas and chimpanzees.
- Emma Nelson and Susanne Shultz are currently investigating how 2D:4D relates to primate mating strategies and the evolution of human sociality.
- Sexual dimorphism in hind limb 2D:4D has been demonstrated in mice by two studies by both John Manning and Marc Breedlove's research groups. There is some evidence to suggest that this effect is not seen in all mouse strains.
- Nancy Burley's research group has demonstrated sexual dimorphism in zebra finches, and found a correlation between digit ratio in females and the strength of their preference for sexually selected traits in males.
- Front limb D2:D3 has shown to be influenced by prenatal alcohol exposure in female rats.
- Alžbeta Talarovičová and collaborators found in rats that elevated testosterone during the prenatal period can influence 4D length, the 2D:4D ratio, and open field motor activity.
- Peter L. Hurd, Theodore Garland, Jr., and their students have examined hindlimb 2D:4D in lines of mice selectively bred for high voluntary wheel-running behavior (see experimental evolution). These high-runner mice exhibit increased 2D:4D. This apparent "feminization" is opposite to the relation seen between 2D:4D and physical fitness in human beings, and is difficult to reconcile with the idea that 2D:4D is a clear proxy for prenatal androgen exposure in mice. The authors suggest that 2D:4D may more accurately reflect effect of glucocorticoids or other factors that regulate any of various genes.
Read more about this topic: Digit Ratio
Famous quotes containing the words digit, ratio, research and/or animals:
“Bless my soul, Sir, will you Britons not credit that an American can be a gentleman, & have read the Waverly Novels, tho every digit may have been in the tar-bucket?”
—Herman Melville (1819–1891)
“Official dignity tends to increase in inverse ratio to the importance of the country in which the office is held.”
—Aldous Huxley (1894–1963)
“The great question that has never been answered, and which I have not yet been able to answer, despite my thirty years of research into the feminine soul, is “What does a woman want?””
—Sigmund Freud (1856–1939)
“Thou almost mak’st me waver in my faith
To hold opinion with Pythagoras,
That souls of animals infuse themselves
Into the trunks of men.”
—William Shakespeare (1564–1616)