Во прилог на парењето на животните и отсуството на пенилната коска кај човекот, би ме интересирало кој од вас тука би можел да ја поедностави оваа еволуциска промена и проблематика и зошто кај човекот при еволуцискиот процес таа се изгубила? Пред некоја година излезе и теорија дека кај мажите освен бакула, постоеле и други ковчиња на пенисот, со кои тие ги стругале остатоците од семената течност од ривалите во вагината на посакуваната/оплодена жена при чинот на пенетрација.
"Despite slang terms that imply otherwise, the human penis contains no bones. The same cannot be said for many of our closest evolutionary relatives: Chimpanzees and bonobos both have penis bones (a macaque one is pictured), also known as bacula. To find out why some primates have the feature whereas others don’t, researchers traced the bone’s evolutionary history through time. The baculum first evolved between 145 million and 95 million years ago, the team reports online today in the Proceedings of the Royal Society B. That means it was present in the most recent common ancestor of all primates and carnivores. Why some descendants, like humans, lost their bacula appears to be due to differences in mating practices: In primates, the presence of a penis bone was most tightly correlated to increased intromission duration, i.e. how long the penis penetrates the vagina during intercourse. Longer intromission times often occur in species with polygamous mating practices—where multiple males mate with multiple females—as seen in bonobos and chimps, but not humans. This system creates an intense competition for fertilization, and one way for males to reduce a female’s access to additional mates is to spend more time having sex with her themselves. The penis bone facilitates this by supporting the penis during sex and keeping the urethra open."
Бтв, хомосексуализмот е приметен и кај делфините и некои видови примати, толку од тврдењата дека е тоа некаква социолошка девијација. Мислам дека има и регистрирани шимпанза и други животни кои се самозадоволувале т.е. правеле автофелацио.
Како дополнение.
"Our findings suggest that the baculum plays an important role in supporting male reproductive strategies in species where males face high levels of postcopulatory sexual competition," said lead author Matilda Brindle in a press release. "Prolonging intromission helps a male to guard a female from mating with any competitors, increasing his chances of passing on his genetic material."
To put it another way, having a baculum extends the duration of intromission, or vaginal penetration, and in animals where this needs to go on awhile in order to prevent the females from toddling off and finding someone else to have sex with right away, the males need some strategy for keeping her engaged longer than, say, three minutes. If he can do that, his chances of passing along his genes is much higher. Hence, the bone.
In primates, there seems to be a correlation between the length of the baculum and the duration of intromission: the longer copulation takes, the longer the baculum. For instance, the little primate called an aye-aye (Daubentonia madagascariensis), found only on Madagascar, has a very long baculum in proportion to its size, and their copulation usually lasts around an hour. By contrast, a chimpanzee has a very short baculum — only about a quarter to a third of an inch (6 to 8 millimeters) long — and intromission lasts only about seven seconds. In humans, intromission usually takes about two minutes on average. (Sorry, it's just true — don't believe everything you see on the internet.)
The research team also found baculums to be most common in polygamous mammals, and those with very distinct breeding "seasons." Humans, on the other hand, tend to be monogamous, and we observe no regular breeding season (except maybe the three-day weekend), so the fact that we phased out our baculum isn't that perplexing.
"After the human lineage split from chimpanzees and bonobos and our mating system shifted towards monogamy, probably after 2 million years, the evolutionary pressures retaining the baculum likely disappeared," says Dr. Kit Opie in a press release. "This may have been the final nail in the coffin for the already diminished baculum, which was then lost in ancestral humans."
Може да се заклучи дека веројатно нејзиното исчезнување е некаква еволуциска придобивка при „преминувањето“ на човекот од полигамија кон моногамија.
