Professor John Manning is honorary research fellow in the department of sport and exercise science.     

He is best known for his work on digit ratio (or 2D:4D), i.e., the relative length of the index finger (2D) and the ring finger (4D), as a biomarker of prenatal sex steroids. He has pioneered this work by investigating relationships of 2D:4D with various measures of fertility, health, and behaviour. Over the past 20 years, he has published numerous papers and two books that have stimulated digit ratio research in animals and humans.    

He is also an expert on symmetry and has contributed a number of significant studies in humans and animals, especially on symmetry-performance relationships. 

John Manning sat by a window

How did you initially become interested in your field? 

 I am an evolutionary biologist/psychologist. My initial interest was in broad brush issues regarding the origin of sex and the evolution of males and females. By the end of the 1980s I was focussing on neurodevelopment of infants and I published a series of papers on cradling behaviour in apes and humans. From 1990 my research was on health and more precisely on symmetry and digit ratio.   

What are you hoping to achieve with your research?  

Symmetry is a measure of developmental stability. In the mid-90s I published a series of papers on breast asymmetry as a prognostic trait for breast cancer. Practical applications for this are now emerging. Digit ratio is a proxy for prenatal sex hormones.  I have published on its links with sports performance, autism, heart disease, breast cancer, prostate cancer and osteoarthritis  

What are you currently focusing on?  

 Currently, I am looking at income inequality and its effect on prenatal programming, including a range of important diseases (eg cardiovascular disease) and behavioural traits (eg developmental disorders).