Look up in Linguee Suggest as a translation of "anal penetration" Copy. Licentious behaviour. Reflex anal dilatation opening of the anus on lateral traction on the buttocks.
By Joshua Rhett Miller. December 15, pm Updated December 16, am. The study, conducted by a pair of researchers from the University College London, found that prolonged intromission — penetration lasting longer than 3 minutes — was correlated to the presence of a penis bone, or baculum, which vary dramatically in length, width and shape among male mammals that have them.
Skip to search form Skip to main content. Copulatory behaviour and the process of intromission in Anastrepha ludens Diptera: Tephritidae. Daniel L.
One of the most weird and wonderful products of evolution is the penis bone, or baculum. The baculum is an extra-skeletal bone, which means it is not attached to the rest of the skeleton but instead floats daintily at the end of the penis. Depending on the animal, bacula range in size from under a millimetre to nearly a metre long, and in shape, varying from needle-like spines to fork like prongs. Bacula are found in certain species of mammal, but not all.
Scientists also found strong correlations between intromission and baculum length. The findings, detailed in Proceedings of the Royal Society Boffer clarity on the evolutionary significance of the baculum, sometimes described as "the most diverse of all bones. The shape and size of the baculum varies dramatically among mammal species.
A new UCL study examines how the baculum penis bone evolved in mammals and explores its possible function in primates and carnivores - groups where many species have a baculum, but some do not. The baculum has been described as "the most diverse of all bones", varying dramatically in length, width and shape in the male mammals where it is present. The research, published today in the Royal Society journal Proceedings Bshows that the ancestral mammal, like humans, did not have a baculum - but both ancestral primates and carnivores did.
After ejaculatory series, each consisting of several short intromissions 2- to 3-s vaginal penetration and an ejaculation, male golden hamsters adopt an altered copulatory pattern consisting of long intromissions 5- to s penetration with intravaginal thrusting. Receptivity declines and the tendency for the female to attack the male increases at about the time of this shift in copulatory pattern. Because the mean interintromission interval III between short intromissions is about 8 s compared to s between long intromissions, it is possible that females detect this difference and adjust their mating accordingly.
Sign in. Abstract: AbstractHigh-speed photography of electrically monitored rat sexual behavior suggested that the intromission response maY be analyzed into two components: a d et e c t ion component, in which the male makes a variable number of very rapid shallow thrusts around and eventually into the vaginal opening, and a s tim u I a t ion component, which consists of a single deep thrust into the vagina followed immediately by rapid and vigorous withdrawal and dismount. A suggestion is offered which relates the form of the behavior to the presumed method of penile receptor stimulation.
Monogamous relationships, combined with a relatively short period of penetration, may have caused men to lose their penis bones. Erections may be commonly known as "boners," but anyone with even a basic understanding of human anatomy will know that men's penises don't actually contain bones. In this respect, humans are unlike many other species of mammal, including our closest relatives - chimpanzees and bonobos.