The baculum (also penis bone, penile bone, or os penis, or os priapi) is a bone found in the penis of many placental mammals. It is absent in the human penis, but present in the penises of other primates, such as the gorilla and chimpanzee. The bone is located above the male urethra, and it aids sexual reproduction by maintaining sufficient stiffness during sexual penetration. The homologue to the baculum in female mammals is known as the baubellum or os clitoridis – a bone in the clitoris.
The baculum is used for copulation and varies in size and shape by species. Its evolution may be influenced by sexual selection, and its characteristics are sometimes used to differentiate between similar species. A bone in the penis allows a male to mate for a long time with a female, which can be a distinct advantage in some mating strategies. The length of the baculum may be related to the duration of copulation in some species. In carnivorans and primates, the length of the baculum appears to be influenced by postcopulatory sexual selection. In some Chiroptera species, the baculum can also protect the urethra from compression.
It is absent in humans, ungulates (hoofed mammals), elephants, monotremes (platypus, echidna), marsupials, lagomorphs, hyenas, sirenians, and cetaceans (whales, dolphins, and porpoises), among others.
Evidence suggests that the baculum was independently evolved 9 times and lost in 10 separate lineages. The baculum is an exclusive characteristic of placentals and closely related eutherians, being absent in other mammal clades, and it has been speculated to be derived from the epipubic bones more widely spread across mammals, but notoriously absent in placentals.
Among the primates, the marmoset, weighing around 500 grams (18 oz), has a baculum measuring around 2 millimetres (0.079 in), while the tiny 63 g (2.2 oz) galago has one around 13 millimetres (0.51 in) long. The great apes, despite their size, tend to have very small penis bones, and humans are the only ones to have lost them altogether.
In some mammalian species, such as badgers and raccoons (Procyon lotor), the baculum can be used to determine relative age. If a raccoon's baculum tip is made up of uncalcified cartilage, has a porous base, is less than 1.2 g (0.042 oz) in mass, and measures less than 90 mm (3.5 in) long, then the baculum belongs to a juvenile.
Unlike most other primates, humans lack an os penis or os clitoris; however, this bone is present but much reduced among the great apes. In many ape species, it is a relatively insignificant 10–20 mm (0.39–0.79 in) structure. Cases of human penis ossification following trauma have been reported, and one case was reported of a congenital os penis surgically removed from a 5-year-old boy, who also had other developmental abnormalities, including a cleft scrotum. Clellan S. Ford and Frank A. Beach in Patterns of Sexual Behavior (1951), p. 30 say, "Both gorillas and chimpanzees possess a penile bone. In the latter species, the os penis is located in the lower part of the organ and measures approximately three-quarters of an inch in length." In humans, the rigidity of the erection is provided entirely through blood pressure in the corpora cavernosa. An "artificial baculum" or penile prosthesis is sometimes used to treat erectile dysfunction in humans.
The loss of the bone in humans, when it is present in our nearest related species the chimpanzee, is thought to be because humans "evolved a mating system in which the male tended to accompany a particular female all the time to try to ensure paternity of her children" which allows for frequent matings of short duration. Observation suggests that primates with a baculum only infrequently encounter females, but engage in longer periods of copulation that the baculum makes possible, thereby maximizing their chances of fathering the female's offspring. Human females exhibit concealed ovulation also known as hidden estrus, meaning it is almost impossible to tell when the female is fertile, so frequent matings would be necessary to ensure paternity.
It has been speculated that the loss of the bone in humans, when it is present in our nearest related species the chimpanzee, is a result of sexual selection by females looking for honest signals of good health in prospective mates. The reliance of the human penis solely on hydraulic means to achieve a rigid state makes it particularly vulnerable to blood pressure variation. Poor erectile function portrays not only physical states such as age, diabetes, and neurological disorders, but also mental states such as stress and depression.
It has been argued that the "rib" (Hebrew צְלָעֹת ṣəlā‘a, also translated "flank" or "side") in the story of Adam and Eve is actually a mistranslation of a Biblical Hebrew euphemism for baculum, and that its removal from Adam in the Book of Genesis is a creation story to explain this absence (as well as the presence of the perineal raphe– as a resultant "scar") in humans.
Oosik is a term used in Native Alaska cultures to describe the bacula of walruses, seals, sea lions, and polar bears. Sometimes as long as 60 cm (24 in), fossilized bacula are often polished and used as a handle for knives and other tools. The oosik is a polished and sometimes carved baculum of these large northern carnivores.
Oosiks are also sold as tourist souvenirs. In 2007, a 4.5 ft-long (1.4 m) fossilized penis bone from an extinct species of walrus, believed by the seller to be the largest in existence, was sold for $8,000.
It is not implausible that, with natural selection refining their diagnostic skills, females could glean all sorts of clues about a male's health, and robustness of his ability to cope with stress, from the tone and bearing of his penis.
Appeal to consequences, also known as argumentum ad consequentiam (Latin for "argument to the consequences"), is an argument that concludes a hypothesis (typically a belief) to be either true or false based on whether the premise leads to desirable or undesirable consequences. This is based on an appeal to emotion and is a type of informal fallacy, since the desirability of a premise's consequence does not make the premise true. Moreover, in categorizing consequences as either desirable or undesirable, such arguments inherently contain subjective points of view.
In logic, appeal to consequences refers only to arguments that assert a conclusion's truth value (true or false) without regard to the formal preservation of the truth from the premises; appeal to consequences does not refer to arguments that address a premise's consequential desirability (good or bad, or right or wrong) instead of its truth value. Therefore, an argument based on appeal to consequences is valid in long-term decision making (which discusses possibilities that do not exist yet in the present) and abstract ethics, and in fact such arguments are the cornerstones of many moral theories, particularly related to consequentialism. Appeal to consequences also should not be confused with argumentum ad baculum, which is the bringing up of artificial consequences (i.e. punishments) to argue that an action is wrong.Argumentum ad baculum
Argumentum ad baculum (Latin for "argument to the cudgel" or "appeal to the stick") is the fallacy committed when one appeals to force or the threat of force to bring about the acceptance of a conclusion. One participates in argumentum ad baculum when one points out the negative consequences of holding the contrary position (ex. believe what I say, or I will hit you). It is a specific case of the negative form of an argument to the consequences.Baculum thaii
Baculum thaii is a species of Phasmatodea. It lives in Thailand.Canine penis
Male canids have a bulbus glandis at the base of their penises. The penis sometimes emerges from the penile sheath during sexual arousal. During coitus the bulbus glandis swells up and results in a 'tie' (the male and female dogs being tied together). Muscles in the vagina of the female assist the retention by contracting.At the time of penetration, the canine penis is not erect, and can only penetrate the female because it includes a narrow bone called the "baculum", a feature of most placental mammals. When the male achieves penetration, he will usually hold the female tighter and thrust deeply. It is during this time that the male's penis expands and it is important that the bulbous gland is far enough inside for the female to be able to trap it. Unlike human sexual intercourse, where the male penis commonly becomes erect before entering the female, canine copulation involves the male first penetrating the female, after which swelling of the penis to erection occurs, which usually happens rapidly.Male canines are one of the few animals that have a locking bulbus glandis or also known as a "bulb" or "knot", a spherical area of erectile tissue at the base of the penis. During copulation, and only after the male's penis is fully inside the female's vagina, the bulbus glandis becomes engorged with blood. When the female's vagina subsequently contracts, the penis becomes locked inside the female. This is known as "tying" or "knotting". While characteristic of mating in most canids, the copulatory tie has been reported to be absent or very brief (less than one minute) in the African wild dog, possibly due to the abundance of large predators in its environment.Cross of Cong
The Cross of Cong (Irish: An Bacall Buí, "the yellow baculum") is an early 12th-century Irish Christian ornamented cusped processional cross, which was, as an inscription says, made for Tairrdelbach Ua Conchobair (d. 1156), King of Connacht and High King of Ireland to donate to the Cathedral church of the period that was located at Tuam, County Galway, Ireland. The cross was subsequently moved to Cong Abbey at Cong, County Mayo, from which it takes its name. It was designed to be placed on top of a staff and is also a reliquary, designed to hold a piece of the purported True Cross. This gave it additional importance as an object of reverence and was undoubtedly the reason for the object's elaborate beauty.
The cross is displayed at the National Museum of Ireland, Dublin, having previously been in the Museum of the Royal Irish Academy, Dublin. It is considered one of finest examples of metalwork and decorative art of its period in Western Europe.Cuniculina cunicula
The Sri Lankan Stick Insect, (Cuniculina cunicula), is a species of phasmid or stick insect of the genus Cuniculina. It is found in India and Sri Lanka.Epipubic bone
Epipubic bones are a pair of bones projecting forward from the pelvic bones of modern marsupials and most non-placental fossil mammals: multituberculates, monotremes, and even basal eutherians (the ancestors of placental mammals). They first occur in tritylodontids, suggesting that they are a synapomorphy between them and Mammaliformes.
Only placentals, and possibly the early mammaliformes Megazostrodon and Erythrotherium, lack them; in thylacines and sparassodonts, they appear to have become primarily cartilaginous and the osseous element has become strongly reduced or even absent. Trichosurus mimicked placentals in shifting hypaxial muscles attachment sites from the epipubic to the pelvis, losing the respiratory benefits (see below), but otherwise retains large epipubics.In modern marsupials, the epipubic bones are often called "marsupial bones" because they support the mother's pouch ("marsupium" is Latin for "pouch"), but their presence on other groups of mammals indicates that this was not their original function, which some researchers think was to assist locomotion by supporting some of the muscles that flex the thigh.The epipubic bones were first described in 1698 but their functions have remained unresolved. It has been suggested that they form part of a kinetic linkage stretching from the femur on one side to the ribs on the opposite side. This linkage is formed by a series of muscles: each epipubic bone is connected to the femur by the pectineus muscle, and to the ribs and vertebrae by the pyramidalis, rectus abdominis, and external and internal obliques. According to this hypothesis, the epipubic bones act as levers to stiffen the trunk during locomotion, and aid in breathing. It has been suggested that epipubic bones may constrain asymmetrical gaits, though this appears not to be the case.Placentals are the only mammal lineage that lacks epipubic bones, and this absence has been considered to be correlated to the development of the placenta itself; epipubic bones stiffen the torso, preventing the expansion necessary for prolonged pregnancy. This however apparently did not prevent large litter sizes; Kayentatherium is now known to have given birth to litters of 38 undeveloped young, a considerably higher number than living monotremes or marsupials. However, vestiges of the epipubic bone may survive in a common placental characteristic, the baculum.Homalopoma baculum
Homalopoma baculum, common name the berry dwarf turban, is a species of small sea snail with calcareous opercula, a marine gastropod mollusk in the family Colloniidae.Icelandic Phallological Museum
The Icelandic Phallological Museum (Icelandic: Hið íslenzka reðasafn), located in Reykjavík, Iceland, houses the world's largest display of penises and penile parts. The collection of 280 specimens from 93 species of animals includes 55 penises taken from whales, 36 from seals and 118 from land mammals, allegedly including Huldufólk (Icelandic elves) and trolls. In July 2011, the museum obtained its first human penis, one of four promised by would-be donors. Its detachment from the donor's body did not go according to plan and it was reduced to a greyish-brown shriveled mass that was pickled in a jar of formalin. The museum continues to search for "a younger and a bigger and better one."Founded in 1997 by since-then retired teacher Sigurður Hjartarson and now run by his son Hjörtur Gísli Sigurðsson, the museum grew out of an interest in penises that began during Sigurður's childhood when he was given a cattle whip made from a bull's penis. He obtained the organs of Icelandic animals from sources around the country, with acquisitions ranging from the 170 cm (67 in) front tip of a blue whale penis to the 2 mm (0.08 in) baculum of a hamster, which can only be seen with a magnifying glass. The museum claims that its collection includes the penises of elves and trolls, though, as Icelandic folklore portrays such creatures as being invisible, they cannot be seen. The collection also features phallic art and crafts such as lampshades made from the scrotums of bulls.
The museum has become a popular tourist attraction with thousands of visitors a year and has received international media attention, including a Canadian documentary film called The Final Member, which covers the museum's quest to obtain a human penis. According to its mission statement, the museum aims to enable "individuals to undertake serious study into the field of phallology in an organized, scientific fashion."Isalo serotine
The Isalo serotine (Neoromicia malagasyensis) is a vespertilionid bat of Madagascar in the genus Neoromicia. It is known only from the vicinity of the Isalo National Park in the southwestern part of the island, where it has been caught in riverine habitats. After the first specimen was caught in 1967, it was described as a subspecies of Eptesicus somalicus (now Neoromicia somalica) in 1995. After four more specimens were collected in 2002 and 2003, it was recognized as a separate species. Because of its small distribution and the threat of habitat destruction, it is considered "Endangered" in the IUCN Red List.
Neoromicia malagasyensis is a relatively small species, with a forearm length of 30 to 32 mm (1.2 to 1.3 in) and a body mass of 3.9 to 9 g (0.1 to 0.3 oz). The fur is dark brown above and mixed buff and gray below. The ears are translucent and the tibia is short. The baculum (penis bone) resembles that of N. melckorum, but is smaller. The duration of the echolocation call, which consists of a component with rapidly falling frequency and one showing more stable frequency, averages 4.9 ms and the interval between calls averages 69.1 ms.Maribaculum
Maribaculum is a genus in the phylum Proteobacteria (Bacteria). The name Maribaculum derives from: Latin noun mare, the sea; Latin neuter gender noun baculum, a stick or rod; New Latin neuter gender noun Maribaculum, rod from the sea.Medauroidea extradentata
Medauroidea extradentata, commonly known as the Vietnamese or Annam walking stick, is a species of the family Phasmatidae. They originate in Vietnam and are commonly found in tropical forests there. They eat a variety of foliage, though in captivity they commonly eat blackberry bramble, hawthorn, oak, red maple and rose.Penis
A penis (plural penises or penes ) is the primary sexual organ that male animals use to inseminate sexually receptive mates (usually females and hermaphrodites) during copulation. Such organs occur in many animals, both vertebrate and invertebrate, but males do not bear a penis in every animal species, and in those species in which the male does bear a so-called penis, the penes in the various species are not necessarily homologous. For example, the penis of a mammal is at most analogous to the penis of a male insect or barnacle.The term penis applies to many intromittent organs, but not to all; for example the intromittent organ of most cephalopoda is the hectocotylus, a specialised arm, and male spiders use their pedipalps. Even within the Vertebrata there are morphological variants with specific terminology, such as hemipenes.
In most species of animals in which there is an organ that might reasonably be described as a penis, it has no major function other than intromission, or at least conveying the sperm to the female, but in the placental mammals the penis bears the distal part of the urethra, which discharges both urine during urination and semen during copulation.Perineal raphe
The perineal raphe is a visible line or ridge of tissue on the human body that extends from the anus through the perineum. It is found in both males and females, and arises from the fusion of the urogenital folds.
In males, this structure continues through the midline of the scrotum (scrotal raphe) and upwards through the posterior midline aspect of the penis (penile raphe). It also exists deeper through the scrotum where it is called the scrotal septum. It is the result of a fetal developmental phenomenon whereby the scrotum and penis close toward the midline and fuse.It has been argued that the "rib" in the biblical story of Adam and Eve is actually a mistranslation of a Biblical Hebrew euphemism for baculum (penis bone), and that its removal from Adam in the Book of Genesis is a creation narrative to explain its absence in humans, as well as the presence of the raphe– as a resultant 'scar'.Pipistrellus raceyi
Pipistrellus raceyi, also known as Racey's pipistrelle, is a bat from Madagascar, in the genus Pipistrellus. Although unidentified species of Pipistrellus had been previously reported from Madagascar since the 1990s, P. raceyi was not formally named until 2006. It is apparently most closely related to the Asian species P. endoi, P. paterculus, and P. abramus, and its ancestors probably reached Madagascar from Asia. P. raceyi has been recorded at four sites, two in the eastern and two in the western lowlands. In the east, it is found in open areas and has been found roosting in a building; in the west it occurs in dry forest. Because of uncertainties about its ecology, it is listed as "Data Deficient" on the IUCN Red List.
With a forearm length of 28.0 to 31.2 mm (1.10 to 1.23 in), Pipistrellus raceyi is small to medium-sized for a species of Pipistrellus. The body is reddish above and yellow-brown below. The wings are dark and the feet are small. Males have a long penis and baculum (penis bone), which is somewhat similar to those of P. endoi, P. abramus and P. paterculus. In the skull, the rostrum (front part) is less flat than in related species and the supraorbital ridges (above the eyes) are prominent. The fourth upper premolar does not touch the upper canine and the second lower premolar is well-developed.Sardolutra
Sardolutra ichnusae is an extinct species of otter from the late Pleistocene of Sardinia. It was originally described as Nesolutra ichnusae. It was a rather small species of otter, probably living in the sea. Among its characteristics is a relatively very large baculum, larger than in any living otter.
The species probably evolved from a species of Lutra, maybe L. castiglionis.Tapinoma baculum
Tapinoma baculum is an extinct species of ant in the genus Tapinoma. Described by Zhang in 1989, fossils of the species were found in China.White-ankled mouse
The white-ankled mouse (Peromyscus pectoralis) is a species of rodent in the family Cricetidae.
It is found in Mexico and in New Mexico, Oklahoma and Texas in the United States.The white-ankled mouse is commonly found in coexistence with the Brush mouse and Texas mouse (P. boylii and P. attaweri). Often, the sympatric overlap in characteristics between these species makes it difficult to identify a specific species. The most distinguishing feature of the white-ankled mouse, and the one most used to identify the species, is the baculum of males (Hooper 1958). The tip of the white-ankled mouse’s baculum is long and cartilaginous, whereas the tip of the Brush and Texas mouse is short and rounded (Clark 1952 and Hooper 1958).Ziony Zevit
Ziony Zevit (born February 13, 1942) is an American scholar of biblical literature and Northwest Semitic languages and a professor at American Jewish University.