At least during the missionary positionThe male Australian aborigines were hunting with their penises. With copulating penises. These were the results of Dutch research, published in on-line British Medical Journal, which showed that during sexual intercourse, more specifically the male-on-top "missionary position", the penis took the shape of a boomerang.
Well, some guys (Tom Cruise is one example) have this shape in any position... This because some men have naturally crooked penises. But at some moments, we all have crooked penises. Previously, it was thought that the penis remained right, during the missionary position, or that it took an "S" shape.
This study explains why women enjoy this position...
"These results are very important for all sexologists. Results of the research could be useful in determining the chances of conception during intercourse. " lead researcher Professor Willibrord Weijmar Schultz, from the Department of Gynecology, University Hospital Groningen, told Reuters.
The team employed magnetic resonance (MRI) to investigate couples engaged in intercourse. 13 experiments were performed with 8 couples and 3 single women, all subjects being older than 18 and with a low to average BMI index, for investigating male and female anatomy during intercourse and masturbation.
The MRI scanner had to be enlarged in order to accommodate two people and to be able to make this investigation, and the results have been achieved over a period of seven years.
The MRI images revealed that during intercourse in the "missionary position" the penis took the shape of a boomerang and 1/3 of its length was represented by its root, while the pendulous body of the penis made the rest of 2/3. The erect penis's pendulous part moved upwards forming an angle of about 120 degrees at the root of the penis, and relatively parallel to the woman's spine. This has always occured in the missionary position and the phenomenon appeared no matter the depth of penetration.
The scanning revealed that the complete penetration the penis filled up the anterior fornix (fornix is the deepest portion of the vagina) or the posterior fornix, and the enormous size of the average penis in erection (root plus pendulous part) was 22 cm (9 in)!).
Sexual arousal in women was found to make the uterus raise by 2.4 cm (1 in) and the anterior vaginal wall to turn longer.