Female Penis Research Articles

Imposex in Lepsiella vinosa from Southern Australia

The deformity ‘imposex’, which is the growth of a penis and/or vas deferens in females of dioecious gastropods, has been associated with the use of tributyltin based marine antifouling paints. We report on a survey of Lepsiella vinosa in Southern Australia which detected imposex at 14 of 20 sites sampled. Laboratory experiments suggested that although tributyltin is important in the development of imposex, other factors including copper, paint matrix and environmental stress may also induce this deformity.

The rough tingleOcenebra erinacea (Neogastropoda: muricidae): An exhibitor of imposex in comparison toNucella lapillus

The muricid gastropodOcenebra erinacea exhibits imposex (occurrence of male parts in addition to the female genital duct), a phenomenon which is caused by tributyltin (TBT)-compounds leached from ships’ antifouling paints. Five stages of imposex development (1–5) with two different types at stage 1 can be distinguished and are documented with SEM-photographs for the first time. Four additional alterations of the genital tract are shown. Close to harbours and marinas,O. erinacea females exhibit malformations of the pallial oviduct, which seem to inhibit copulation and capsule formation resulting in sterilization. The TBT accumulation in the whole body and the accumulation pattern in single tissues are described; contrary to other prosobranchs no sexrelated differences were found. The VDS, uncubed RPS and average female penis length of a population were analysed regarding their quality as parameters for TBT biomonitoring. On the background of the ecology of this species the VDS is chosen as the best index. Only in highly polluted areas should the uncubed RPS be used as a secondary parameter. A statistical study, based on the analysis of natural populations ofNucella lapillus andO. erinacea, allows a comparison of the specific TBT sensitivity of the two bioindicators. Dogwhelks exhibit a greater TBT sensitivity, namely at slightly polluted sites, nevertheless even here rough tingles develop obvious imposex characteristics.

The morphological expression of imposex in Hinia reticulata (Gastropoda: Buccinidae): a potential indicator of tributultin pollution

Specimens from the prosobranch Hinia reticulata collected along the coast of Brittany and Normandy from 1988 to 1991 exhibited imposex (occurrence of male parts in addition to the female genital duct) in response to tributyltin (TBT) pollution. Four stages of imposex development (1 to 4) with two different types in the Stages 1, 3 and 4 could be distinguished and have been documented with scanning electron micrographs for the first time. Furthermore, three additional alterations of the genital tract are shown. Neither TBT-induced sterilization nor sex change occurred. TBT accumulation in whole body and selected tissues is described and sex-related differences are shown. The VDS (vas deferens sequence) index, cubed and uncubed RPS (relative penis size) index and average female penis length of a population were analysed with regard to their quality as indices for TBT biomonitoring. Based on the way imposex develops in this species the VDS is recommended as the most valid index. Only in highly polluted areas should the uncubed RPS be used as a second index.

Hinia reticulata and Nucella lapillus. Comparison of two gastropod tributyltin bioindicators

Hinia reticulata and Nucella lapillus (collected from 1989 to 1991 at Pointe de Pleneuf and Mean Melen, France, respectively) exhibit imposex in response to tributyltin (TBT) pollution leached from antifouling paints and proved to be good TBT bioindicators. H. reticulata was kept for 18 mo under TBT-free conditions in the laboratory, but no evidence for imposex remission was found. A second series of experiments showed that food chain uptake of TBT from a contaminated diet is an important mode of TBT exposure in H. reticulata. Comparative tank experiments with H. reticulata and N. lapillus demonstrated that the same type of TBT exposure resulted in comparable TBT body burdens, biological concentration factors, and imposex development in both species [measured as increase of VDS (vas deferens sequence index), uncubed RPS (relative penis size index) and average female penis length]. Differences in imposex development of natural and laboratory populations are discussed against the background of different types of TBT contamination of their food. A statistical study, based on an analysis of natural populations of both prosobranch species, makes a comparison of the specific TBT sensitivity of the two bioindicators possible. As a consequence it is proposed that TBT biomonitoring programs in Europe should use both prosobranchs as indicator species.

TBT-induced imposex in the dogwhelk, Nucella lapillus: Geographical uniformity of the response and effects

The imposex response of the dogwhelk, Nucella lapillus, to tributyltin (TBT) pollution has been investigated in adults taken from four UK populations geographically separated over 10° of latitude. Exposure to TBT water concentrations of c.1 and 17 ng Sn/litre over a period of 12 weeks resulted in similar levels of accumulation of TBT within the body tissues and similar increases in female penis length in all four populations. The features are imposex in N. lapillus populations in south-west Brittany are described; they follow the same pattern as found in earlier surveys of the southern England coast, including sterilisation of females, population decline and disappearance of the species close to TBT sources. The evidence of these two investigations indicates that the level of sensitivity and development of imposex as a response to TBT pollution is uniform in N. lapillus throughout its distributional range.

The Effects of Tributyltin on Dogwhelks (Nucella Lapillus) From Scottish Coastal Waters

The common dogwhelk (Nucella lapillus) is a dioecious species. However, on exposure to low concentrations (<1 ng I-1, Gibbs et al., 1987) of tributyltin (TBT) females develop certain male sexual characteristics, notably a penis and vas deferens. This phenomenon, first reported by Blaber (1970) in dogwhelks from the Plymouth area, and later termed 'imposex' (Smith, 1981), is now recognised as the most sensitive and straightforward way to identify contamination of coastal areas by TBT. The degree of imposex may be readily quantified as the relative penis size index (RPSI), which expresses the relative bulk of the penes in females and males from a given sample. It is calculated as (mean cubed female penis length/the mean cubed male penis length) x 100% (Gibbs et al., 1987). Gibbs et al. (1987) have examined the development of imposex in greater detail, and have divided the process into six stages (known as the vas deferens sequence, or VDS) based upon the degree of development of the vas deferens and penis in the female animal. This classification enables an assessment to be made of the reproductive ability of an animal. Stages 1 to 4 show a progressive development of the penis and vas deferens. At a VDS of 5, vas deferens tissue proliferates over the opening of the reproductive tract, blocking it, and subsequently causing sterility due to the inability of the animal to release egg capsules. Aborted egg capsules then gradually accumulate in the capsule gland (stage 6). The vas deferens sequence index, VDSI, is the mean VDS in a given sample of females.

Copper, Zinc, and Organotin as Long-Term Factors Governing the Distribution of Organisms in the Fal Estuary in Southwest England

Evidence of long-term metal pollution in the Fal Estuary is provided by analyses of Cu in oyster (Ostrea edulis) communities extending over more than 120 yr and by analyses of Cu and Zn in sediments dating back to 1921. Indications are that levels of Cu pollution from mining have declined very slowly but that Zn pollution has not. In Restronguet Creek, the most heavily polluted area, metal levels in waters and sediments are elevated by orders of magnitude. The invertebrate fauna of the creek is limited, but far richer than might be predicted from laboratory toxicity data. The cockleCerastoderma edule exemplifies organisms that are excluded from the creek owing to the toxicity of dissolved Cu, whereasOstrea edulis, by virtue of its innate tolerance to Cu and Zn, grown in the Iower reaches. On the other hand, the population of the ragwornNereis diversicolor, which penetrates into the most heavily polluted areas, is demonstrably far more tolerant of Cu and Zn than population from clean areas and appears to be a tolerant strain. To a considerable degree, therefore, the distribution of species is dependent not only on the innate ability of some species to tolerate Cu and Zn, but on the capacities of other populations to develop metal resistance and thereby maintain their original range of distribution. Present-day problems in the Fal Estuary appear to stem not only from mining wastes but also from the increased usage of tributyltins in antifouling paints. In the dogwhelkNucella lapillus, the incidence of imposex (the appearance of a penis and other male characters in females) is virtually 100% at sites along the English Channel coast of southwest England. The degree of imposex is related to the body concentration of hexane-extractable organotin, which includes both tributyltin and dibutyltin fractions. The highest degree of imposex, where the female penis approaches that of the male in size, occurs in the Fal Estuary; also, in some males the penis becomes deformed. Populations of dogwhelks have declined dramatically in this estuary, and are also characterised by the presence of relatively fewer females and by the absence of juveniles and egg capsules. Reproductive failure in females is now known to be caused by blockage of the pallial oviduct during the development of imposex.

The effects of tributyltin (TBT) accumulation on adult dog-whelks, Nucella lapillus: long-term field and laboratory experiments

Populations of the gastropod, Nucella lapillus (L.), normally one of the commonest of rocky-shore macroinvertebrates, have recently suffered from declining numbers at many sites along the south coast of England. Bryan et al. (1986) showed that these declining populations exhibited a high degree of imposex (the induction of a penis and vas deferens in females) and that imposex was almost certainly caused by tributyltin (TBT) compounds leached from ships' antifouling paints. Evidence implicating TBT compounds in the development of imposex included: (1) a good relationship between the degree of imposex and the proximity of affected populations to harbours and marinas; (2) in Plymouth Sound, the degree of imposex increased dramatically between its discovery in 1969 (Blaber, 1970) and 1985, thus coinciding with the introduction and increasing usage of TBT-based paints; (3) tissue concentrations of tin as TBT increased consistently with the degree of imposex; (4) animals transplanted from a ‘clean’ area to a harbour site absorbed TBT and developed imposex; (5) preliminary experiments showed that imposex was induced by exposure to 20 ng/1 of tin as TBT leached from a TBT-based paint; (6) TBT is implicated in the induction of imposex in other stenoglossan gastropods including Nassarius obsoletus (Say) (Smith, 1981) and Ocenebra erinacea (L.) (Féral & Gall, 1982).

Reproductive Failure in Populations of the Dog-Whelk, Nucella Lapillus, Caused by Imposex Induced by Tributyltin from Antifouling Paints

The development of male characters, notably a penis and a vas deferens, on the female (the phenomenon of ‘imposex’) of the dog-whelk, Nucella lapillus, is described. Three stages are recognized: an ‘early’ stage involving the formation of a vas deferens and a small penis, an ‘intermediate’ stage characterized by the enlargement of the female penis to a size approaching that of the male and a ‘late’ stage during which the female opening (vulva) is occluded by overgrowth of vas deferens tissue. This blockage of the pallial oviduct prevents the release of egg capsules and renders the female sterile. The extent and cause of such reproductive failure is evident from the high incidence of females containing aborted capsules in declining populations close to sources of tributyltin (TBT) contamination. These same populations comprise fewer females than expected and it would appear that the accumulation of aborted capsules within the pallial oviduct eventually causes the premature death of the female.

Données sur la biologie sexuelle des Rissoidae (Mollusca: Prosobranchia) / On the sexual biology of Rissoidae (Mollusca, Prosobranchia)

Several Rissoidae species from the Posidonia-beds of Villefranche-sur-Mer were studied. The occurrence of a penis was noticed in all the juveniles, immatures, males and females. The survey of the annual cycle of four species, with histological control, carried out in Villefranche-sur-Mer, do not support the hypothesis of a successive hermaphrodism. Throughout the annual cycle, the size of the female penis changes while that of the male penis does not. Observations made on several other species collected in other locations (Banyuls-sur-Mer, Roscoff, Galway-Ireland) show that the occurrence and size of the penis in females vary according to the geographical origin. The comparison of the penis morphology shows affinities between species studied.

The "bedrock" of masculinity and femininity: bisexuality.

From his first psychoanalytic writings to his last, Freud was concerned about the relationship of biological forces, which he called the "bedrock," to human psychology. No such theme was more constant than constitutional bisexuality, which he always believed influenced object choice and the degree of a person's masculinity and femininity. In analysis, one could not penetrate the wish for a penis in females or the repudiation (fear of) femininity in males, because they are the "bedrock," ultimately determined by consitutional bisexuality. This paper suggests that, recent work showing how biological forces can change gender behavior in animals notwithstanding, these fundamental qualities in men and women can be caused by quite nonbiological forces-the family psychodynamics that help shape gender identity in infancy.