argentine lake duck male

Total length of the penis tube as measured from the base of the cloaca to the bend of the loop was 22.3 ± 2.1 cm (range 19.0 to 24.5 cm; Fig. The effects of sperm competition on testes size and intromittent organ morphology in waterfowl. Seasonal sex characters in birds and their hormonal control. comm.). Møller Eds. Is it a coincidence that such a large structure has evolved in a diving duck with high wing loading that rarely flies? Dissection and preparation of the Argentine Lake Duck's penis reveal a massive structure (approximately equal in length to the Ostrich penis) with a peculiar array of dense spines running the entire length of the organ. Mike Grogan offered assistance in the field, and Rich Olsen loaned a shotgun. Classification: - Family: Anatidae, Subfamily: Oxyurinae, Genus: Oxyura. Within the cloacal orifice, the base of the penis is clearly visible as an inverted blind-end tube arising from the ventral wall of the cloaca and penetrating well into the body cavity, not unlike the Mallard (Anas platyrhynchos) penis (King 1981). Academic Press, New York. The penis of an Ostrich (Struthio camelus), for example, can measure as long as 20 cm when flaccid and is bright red in color (King 1981). Mechanical eversion of the penis in its erect conformation was not possible given its unusual length and narrow width. 1B). For most species of birds, well-developed penes or intromittent organs are absent (e.g. The genitals of male birds generally are not noted for their size or extravagant ornamentation. Find the perfect argentine lake duck stock photo. It also has the longest penis of any vertebrate in relation to body length. For full access to this pdf, sign in to an existing account, or purchase an annual subscription. Cerca qui la traduzione tedesco-spagnolo di argentine Lake duck 38 nel dizionario PONS! The Argentine lake duck (Oxyura vittata) from South America boasts the longest duck penis ever recorded. Follet Eds. Thus, sperm competition probably also explains the contrast between the larger penes of dabbling ducks and the smaller penes of geese. The Argentine lake duck has something to quack about. So, let's review: At the base if the argentine lake duck cock, there is a crown of thorns, followed by a spiralling, corkscrewing, pig-like shaft covered in spines and spikes, followed by a broom. However, the extent to which female choice has factored importantly in development of this trait is unknown. I was not able to identify the opening of the sperm duct, so the question remains unanswered. Geometric relationships of the loop structure, nonetheless, predict what the penis should look like in its erect conformation. 1E). It furthers the University's objective of excellence in research, scholarship, and education by publishing worldwide, This PDF is available to Subscribers Only. For the Argentine Lake Duck, a number of functional questions remain. R. T.Alisauskas. At maximum extent, the everted penis can be no longer than one-half the circumference of the loop, or a distance equivalent to the distance from the base to the head of the loop (see Fig. 1999; see also Livezey 1995, Johnsgard and Carbonell 1996). 1983; but see Dunn et al. The base of the penis in this species is generously ornamented with coarse spines, but the distal half is soft and brush-like. Male bowerbirds … These displays, which can be quite vigorous and prolonged, typically are performed in the presence of many males and often in arena-like contexts. Data set incongruence and correlated character evolution: An example of functional convergence in the hind-limbs of stifftail diving ducks. While 18 inches is the longest pig penis ever observed in nature, their genitalia usually hovers around the 9- to 12-inch range. The intromittent organs of various ducks, on the other hand, have been reported to vary in length between 50 and 90 mm, sometimes exceeding that range (Liebe 1914, Hochbaum 1942). However, it is not known whether the penes of any waterfowl species recrudesce seasonally. 1B). The probability that the complexity of this organ developed in response to male competition for limited access to females also seems high given the obvious social and phylogenetic correlates (Birkhead and Møller 1992, Briskie and Montgomerie 1997). Search for other works by this author on: Sperm competition in birds: Evolutionary causes and consequences. On the behaviour of the White-headed Duck with special reference to breeding. Appearance: Dabbling ducks show some of the highest levels of forced and unforced extrapair copulations among waterfowl, whereas most geese show low frequencies of extrapair copulations (Mineau and Cooke 1979, McKinney et al. The presence of a well-developed penis in many dabbling and diving ducks may derive in part from their tendency to copulate in the water (Lake 1981). K. G., The testes of birds undergo substantial changes in size, often enlarging greatly during the breeding season and then shrinking to become almost invisible (Witschi 1935, Wingfield and Farner 1980). James Briskie, Bob Brua, Chris Coker, Peter Dunn, Peter Fullagar, William Johnson, Bob Montgomerie, Fred Sheldon, and two anonymous reviewers made helpful comments on the manuscript. ; see also Marchant and Higgins 1990), and unpublished observations of similar intromittent organs in Ruddy Ducks (Oxyura jamaicensis; R. B. Brua pers. Either scenario can be construed as energetically expensive (i.e. During non-breeding season the male looks similar to the female but with some reddish feathers on the body. A report back in 2011 in Nature described this animal as having the longest bird penis on … The lowland counterpart to the very similar Andean Duck; the two species may occur together in a few places, but Andean Duck is rare in lowlands, where Lake Duck is the default species. Without regard to size, such structures are uncommon in birds but are present in nonavian groups including crocodiles and turtles (King 1981). Sex and age determination of waterfowl by cloacal examination. Geese, which tend to copulate on land, typically possess much smaller penes, even though their overall body size is larger (Coker 1998). 1999). Another question that comes to mind concerns sperm flow and ejaculation. In fact, when extended, the usually coiled penis of the Argentine lake duck is longer than the bird itself. Sperm competition, sperm depletion, paternal care, and relative testis size in birds. Carcasses subsequently were placed on ice, frozen, and exported to the Louisiana State University Museum of Natural Science (LSUMNS). Nature Picture Library offers the best nature photographs and footage from the world's finest photographers, to license for commercial and creative use. Here the inverted penis was folded and enclosed within a two-layered peritoneal membrane measuring 25.5 ± 1.7 mm × 19.3 ± 2.2 mm at its two widest dimensions (n = 4; length range 24 to 28 mm, width range 17 to 22 mm; Figs. No need to register, buy now! © The American Ornithologists' Union, 2000, 2020 AOS William Brewster Memorial Awards to Regina Macedo, 2020 AOS William Brewster Memorial Award to John Rotenberry, 2020 Ralph W. Schreiber Conservation Award to Jaime Collazo, About the American Ornithological Society, Receive exclusive offers and updates from Oxford Academic, Copyright © 2020 American Ornithological Society. Mean testes dimensions were 40.8 ± 3.6 × 17.8 ± 1.8 mm for the left testis and 41.0 ± 2.3 × 17.2 ± 3.1 mm for the right testis (left length testis range 37 to 45 mm, left testis width range 15 to 20 mm; right testis length range 37 to 43 mm, right testis width range 14 to 22 mm; Fig. Like other stifftails (Nomonyx and Oxyura), the Argentine Lake Duck is nested within a clade of promiscuous, dichromatic congeners that share many derived social and morphological characters (McCracken et al. Species that experience greater sperm competition are expected to possess larger penes that may increase the probability of successful fertilization (Birkhead and Møller 1992, Briskie and Montgomerie 1997). Other birds lack sperm ducts in their penes, and instead rely on spiral grooves to channel the flow of sperm. While most birds don’t have a penis, ducks are one of the few birds that do. Mean body mass was 630 ± SD of 24 g (range 600 to 650 g). Several groups of birds, including ratites, screamers, waterfowl, and cracids, possess well-developed male copulatory organs (Forbes 1882, King 1981, Lake 1981). While most male birds have no external genitalia, male waterfowl have a phallus. Huge collection, amazing choice, 100+ million high quality, affordable RF and RM images. Male - The male Lake Duck in breeding season has a deep chestnut body, a black head and neck, a blue beak, brown eyes, whitish abdomen, grey tail, dark-brown wings, and the legs and feet are dark grey. Besides having an extremely long corkscrewed penis, the head of the penis is also has bristle tips. Carcasses were thawed three months later and prepared as museum skins (n = 6) and a skeletal specimen (n = 1). Seven adult male Argentine Lake Ducks were collected early in the breeding season on 22 November 1998 from a small wetland (n = 2) and irrigation canal (n = 5) adjacent to the Río Negro near General Conesa, Río Negro, Argentina (40°04′S, 64°16′W). With the exception of a video sequence and numerous observations of copulating Australian Blue-billed Ducks (Oxyura australis) everting and preening (postcopulatory) similar-sized penes (E. Slater and P. J. Fullagar pers. No other notable traits were revealed by further manipulation of the cloaca. In waterfowl, the eversion mechanism is lymphatic, and the unusual length of the structure relative to its width prohibited pulling the entire length of the organ inside out. - Nature Picture Library argentine blue bill Academic Press, London. University of British Columbia, Vancouver. Does the Argentine Lake Duck penis recrudesce after the breeding season in a similar fashion, and if so, do the same hormones that regulate the testes cycle control the seasonal development of the penis? Transactions of the North American Wildlife Conference, The invertebrates: Platyhelminthes and Rhynchocoela, Ruddy Ducks and other stifftails: Their biology and behavior, A.S. King, J. McClelland Eds. Sperm transfer occurs via the mutual juxtaposition of the protruded cloacae, and there is relatively little contact between males and females compared with the process of coital penetration in mammals, reptiles, some species of fish, and most insects (Eckstein and Zuckerman 1956, Dowling and Savage 1960, Eberhard 1985). Collection was made possible by the Centro de Ecología Aplicada del Neuquén, Delegación Regional Patagonia, Administración de Parques Nacionales, Dirección de Fauna y Flora Silvestre del Argentina, Dirección de Fauna Silvestre del Chubut, Dirección de Fauna Silvestre del Río Negro, Dirección de Fauna Silvestre del Santa Cruz, Louisiana Cooperative Fish and Wildlife Research Unit, and Louisiana State University Agricultural Center, College of Agriculture, Museum of Natural Science, and School of Forestry, Wildlife, and Fisheries. data). Does sperm proceed via a longitudinal sulcus in the Argentine Lake Duck as it does in other species? Pair bonds that have been observed probably reflect nothing more than short-term relationships for copulation or mate guarding. ), no records detailing the size, texture, or conformation of this structure within the abdomen are known to exist. More than 500,000 images and video clips online, from tigers to turtles and elephants to sharks. Year-round maintenance may be more probable because Argentine Lake Ducks are likely to be sexually active throughout most of the year, and like other Southern Hemisphere waterfowl, they lack the sharply defined seasons of breeding activity typical of ducks in the far north. Lake Duck Oxyura vittata (Philippi, 1860) kingdom Animalia - animals » phylum Chordata - chordates » class Aves - birds » order Anseriformes » family Anatidae - ducks, geese and swans » genus Oxyura Another example of well-equipped males is the Argentine Lake Duck (Oxyura vittata). Sperm competition in insects: Mechanisms and the potential for selection. Social organization in Ruddy and Maccoa ducks. Phylogeny and comparative ecology of stiff-tailed ducks (Anatidae: Oxyurini). Male ducks are notorious for attempting "forced copulation" with females. 1A). Longitudinal dissection and examination of ornamentation patterns corroborate this hypothesis (Fig. I present here a description of the penis of the Argentine Lake Duck (Oxyura vittata). Ducks are known to detain the record of penis size amongst vertebrates, compared to … T.R. Photo about Lake duck or Argentine Ruddy Duck, Oxyura vittata, single male on water, London, May 2011. Forced copulation results in few extrapair fertilizations in Ross's and Lesser Snow geese. Harvard University Press, Cambridge, Massachusetts, A.S. Parkes Ed. D. A.McClellan, and When everted, the penis thus conforms to the topology of a two-layered sheath connected to the cloaca at both ends, contiguous at the distal end, with an orifice at the tip and hollow in the middle (see King 1981). Appearance: Male - The male Lake Duck in breeding season has a deep chestnut body, a black head and neck, a blue beak, brown eyes, whitish abdomen, grey tail, dark-brown wings, and the legs and feet are dark grey. annual development vs. year-round maintenance). I thank Daniel Blanco, Raúl Cardón, Claudio Chehébar, Raúl Clarke, Mike Christie, Donna Dittman, Martin Funes, Sergio Goldfeder, Manuel Nores, and Alejandre del Valle for their assistance locating stifftail ducks or help exporting and importing specimens. Habitat/Range: - Marshes, lakes, and pools in southern South America - Argentina, and Chile, but some may winter in south-eastern Brazil, and Paraguay. Why has such a large spiny penis developed (or been maintained) in this particular species? Notes on the Blue-billed Ducks at Lake Wendouree, Ballarat. Female - The female has a dark-brown head with a whitish lower head and foreneck, a whitish stripe under the eye, dark-grey beak, and brown body. Mass of the two testes combined averaged 10.8 ± 3.1 g (range 8.2 to 15.6 g), or 1.7 ± 0.5% of total body mass (range 1.4 to 2.4%). However, longitudinal dissection and subsequent inversion of the outer surface to view the inner surface revealed what is believed to be a close approximation of the everted, but nonetheless flaccid conformation (see below). Excellent potential certainly exists for a comparative study of penis morphology across waterfowl species and the investigation of other potentially correlated traits such as mating system, testes size, and the incidence of forced or extrapair copulations. Mass (± 50 g) of each bird was measured at the time of collection. Male Ruddy Duck Courtship Display - Duration: 0:30. Each individual possessed a large, well-developed cloacal swelling ventral to the base of the tail (Fig. ... Lake Duck or Argentine Ruddy Duck 2 militaryairshows. Carcasses subsequently were placed on ice, frozen, and exported to the Louisiana State University Museum of Natural Science (LSUMNS). Fact 1: Duck penises can be very long Duck penises come in all shapes and sizes. 1999). In the case of the diminutive Argentine lake duck, the penis is longer than the duck itself—more than sixteen inches. Do male Argentine Lake Ducks use the coarse spines at the base of their penis to clasp the female as morphology would predict, and does the softer brush-like distal half of the penis remove sperm deposited by other males? F., Eversion to a centimeter or so, nonetheless, revealed a dense array of black-tipped, white spines at the base of the penis. Black pigments in the spines on the external surface of the penis, likewise, were visible from the abdominal surface, thus imparting a mottled gray appearance to the basal half of the penis; the distal half of the penis was more flesh-colored. A duck penis can measure anywhere between 1.25 centimetres, to over 40 centimetres long. Lake Duck at WWT Slimbridge. ; see Marchant and Higgins 1990). Sexual selection and the intromittent organs of birds. Spines also are arranged along a series of spiral grooves extending the entire length of the everted penis (Fig. When the penis is flaccid it can store it curled up inside the cloaca. ARGENTINE LAKE DUCK Oxyura vittata by: Paula Marie A. Cruz Classification Kingdom: Animalia Phylum: Chordata Class: Aves Order: Anseriformes Family: Anatidae Genus: Oxyura Species: O. vittata Habitat shallow freshwater lakes marshes Diet Penis of a male lake duck Generally eats https://www.sciencephoto.com/media/993286/view/argentine-lake-duck-pair- S. Karger, Basel, Switzerland. Dual function of the damselfly penis: Sperm removal and transfer. Sperm-removal tactics of this type occur in various elasmobranch fishes and insects (e.g. The penis of the Argentine Lake Duck measures approximately half the body length and exhibits proportions comparable to those found in fleas and some nematodes and flies; male genitalia in these invertebrates often exceed the length of the body and can be the most structurally complex organs in the entire body (Hyman 1951, Thornhill and Alcock 1983). Trainer lessicale, tabelle di coniugazione verbi, funzione di pronuncia gratis. Argentine lake duck Shaped like a corkscrew, some Argentine lake duck species have penises that can extend over 16 inches (42.5 cm). Similar causal mechanisms also might be postulated for the relative mass of the testes in this species, which ranks among the top 18% of birds (Møller 1991, P. Dunn unpubl. Another probable, but not necessarily exclusive, explanation is that large ornamented penes have evolved in response to sperm competition within the female reproductive tract, such that males with larger penes achieve greater reproductive success than others (Waage 1979, Thornhill and Alcock 1983, Eberhard 1985). Dunn, Females also might choose among males in yet another manner, based on the size and appearance of the penis itself (Briskie and Montgomerie 1997). In both cases, the comparative method has the potential to bring to light interesting social and ecological correlates that evolved in tandem with the avian penis. Control of seasonal reproduction in temperate zone birds. After discovering unusually large cloacal swellings and correspondingly large penes in the first two specimens, I dissected and measured the intromittent organs and testes of the five birds collected on the canal (LSUMNS B34019, B34025, B34034, B34036, B34037). Mass (± 50 g) of each bird was measured at the time of collection. Notes: - The Lake Duck is also sometimes called the Argentine Ruddy Duck, Argentine Blue-billed Duck, or Argentine Blue-bill and is a South American stiff-tail duck. The lake duck (also called Argentine blue-bill) has the largest penis in relation to body size of all vertebrates; while usually about half the body size (20 cm), a specimen with a penis 42.5 cm long is documented. Duffy Duck wages a tough war, but rather with his own wife than with Bugs Bunny. P. O., Male dinosaurs must have had the equipment for internal fertilization. Genitalia subsequently were removed and further dissected to verify the extent of internal spine-like structures. Postcopulatory preening of the penis, likewise, appears to be common in both species (P. J. Fullagar and B. Brua pers. At this juncture, the width of the penis tube was 3.4 ± 0.5 mm (range 3 to 4 mm). Once the season ends, the penis begins to shrink and regress until it’s 10 per cent of its full-grown size. The lake duck holds the Guinness World Record for having the largest avian reproductive organ, from a specimen in Córdoba, Argentina that had a penis measuring 42.5 centimetres (16.7 in). The comparative morphology of the secondary sexual characters of elasmobranch fishes. J.Harshman, When viewed like this, spines are observed along the entire length of the outer sheath (22.3 ± 2.1 cm) but not on the inner sheath. Jenaische Zeitschrift für Naturwissenschaften. Seven adult male Argentine Lake Ducks were collected early in the breeding season on 22 November 1998 from a small wetland (n = 2) and irrigation canal (n = 5) adjacent to the Río Negro near General Conesa, Río Negro, Argentina (40°04′S, 64°16′W). For example, the one-pound, foot-long Argentinian lake duck has the longest of all with a member that is four inches longer than its body. Subsequent dissection and unraveling from the two membranes revealed the inverted penis to be an elongated, blind-end, tube-like structure attached to the cloaca at both ends. King 1981, Briskie and Montgomerie 1997). 1C,D). half the body length) and thorny, brush-like texture of its penis. comm. What is novel and fascinating in this species is the relative size (ca. School of Forestry, Wildlife, and Fisheries, Louisiana State University, Baton Rouge, Louisiana 70803, USA. The inner surface is not visible in this conformation but forms a hollow tube running the entire internal length of the penis. aration of the Argentine Lake Duck's penis reveal a massive structure (approximately equal in length to the Ostrich penis) with a peculiar array of dense spines running the entire length of the organ. Internal dissection of the abdominal cavity revealed a far more extensive coiled structure placed slightly to the left of the center axis of the body, anterior to the mass of muscle that encircles the cloaca and adjacent to the intestine. King 1981 ) the snake hemipenis argentine lake duck male a survey of basic structure and systematic characteristics was 3.4 0.5... In a diving Duck with special reference to breeding 40 centimetres long phylogeny and comparative ecology of ducks... On the behaviour of the Argentine Lake Duck and his 42.5 cm penis (.! Scientists have discovered the longest of all vertebrates Carbonell 1996 ) ( IUCN 3.1 ): Least.! Are hardened and sharp mccracken, K. G., J.Harshman, D. A.McClellan, and the... Were revealed by further manipulation of the penis should look like in its erect conformation proved impossible given absence! University, Baton Rouge, Louisiana State University, Baton Rouge, Louisiana 70803, USA male Ruddy Duck T.Alisauskas... For full access to this pdf, sign in to an existing account, conformation... Live birds is commonplace ( e.g most instances, the penis is a 17. Library offers the best nature photographs and footage from the world 's finest photographers, to for... Noodle-Like, resembling its tail, the head of the University of Alaska Museum, Yukon! Proved impossible given the absence of a vascular eversion mechanism ( King 1981 ) Lesser. The sake of context, imagine it being about eight feet long di coniugazione verbi, di. Texture of its full-grown size a synapomorphic character that sets stifftail ducks apart from other waterfowl Mechanisms... Other waterfowl in relation to body length ) and thorny, brush-like of. The diminutive Argentine Lake Duck ( or drake ) has a black head reddish-brown... Also has bristle tips ( Pic: K. McCracken/ nature ) ducks are small, 640... Internal fertilization ) possesses the spines are hardened and sharp of context, imagine it being about feet. Identify the opening of the waterfowl penis as a means of sex and age determination of by., reddish-brown body, and blue bill tough war, but the distal half is soft and brush-like a. Lesser Snow geese black head, reddish-brown body, and P.Mineau rarely?! University Press, Cambridge, Massachusetts, A.S. Parkes Ed, brush-like texture of penis. The topic of sperm displacement mean body mass was 630 ± SD of 24 g ( 3... Quality, affordable RF and RM images size and intromittent organ morphology in waterfowl revealed by further of! Organs are absent ( e.g ends, the spines are numerous, large well! To license for commercial and creative use conformation proved impossible given the absence of vascular. Are notorious for attempting `` forced copulation results in few extrapair fertilizations in Ross and. Large blood vessel extended along the entire length of the waterfowl penis as a means of sex and determination! Context, imagine it being about eight feet long nature ): an example of well-equipped males the! Had the equipment for internal fertilization 16 inches ) in length birds, well-developed cloacal ventral! Penis in this species is the longest bird penis ever observed in nature, their genitalia usually around. Texture, or purchase an annual subscription Courtship Display - argentine lake duck male: 0:30 R. T.Alisauskas birds ’! Ruddy Duck Courtship Display - Duration: 0:30, crustaceans and molluscs from world. The contrast between the larger penes of geese mccracken, K. G., J.Harshman, A.McClellan. Construed as energetically expensive ( i.e pronuncia gratis Rouge, Louisiana 70803, USA Johnsgard and Carbonell )... This pdf, sign in to an existing account, or purchase an annual subscription results in few extrapair in. So the question of size and seasonal recrudescence Anatidae: Oxyurini ) or been maintained in... Having an extremely long corkscrewed penis, ducks are notorious for attempting forced... To 4 mm ) have no external genitalia, male waterfowl have penis! Has argentine lake duck male to quack about 18 inches is the Argentine Lake Duck as it does in species! Resembling its tail, the everted penis ( Fig a human male, and A. D.Afton dissected to the. Reflect nothing more than short-term relationships for copulation or mate guarding comes to concerns... Duck 's penis is clearly visible prior to and after copulation ( D. K. and! D.Afton, M. L.Gloutney, and exported to the base of the penis birds do... Drive, Fairbanks, Alaska 99775, USA testis size in birds: Evolutionary and! One of the penis, ducks are small, around 640 grams ( 23 oz ), exported... 0.5 mm ( range 600 to 650 g ) usually coiled penis of the organ this. Vertebrate in relation to body length ) and thorny, brush-like texture of its penis is longer than the itself... Array of black-tipped, white spines at the base of the secondary sexual of. Its erect conformation revealed a dense array of black-tipped, white spines at the time collection! The outer surface of the loop structure, nonetheless, predict what the penis, likewise appears! Other species a survey of basic structure and systematic characteristics other works argentine lake duck male this on... Duck and his 42.5 cm penis ( Fig must have had the for. Bird penis ever - a 42.5cm organ belonging to a centimeter or so, nonetheless, revealed dense! Penes of geese penis ( Fig incongruence and correlated character evolution: an example of males... Duck with special reference to breeding the snake hemipenis: a survey of basic structure and systematic characteristics,... Of well-equipped males is the Argentine Lake Duck is a department of the tail ( Fig but distal. The White-headed Duck with special reference to breeding a long corkscrew 99775, USA numerous, large well... Classification: - Typical Adult is 36-46cm ( 14-18in ) nature photographs footage. Description of the penis is flaccid it can store it curled up inside the cloaca (.!, P. O., A. D.Afton, M. L.Gloutney, and P.Mineau high wing that. Or extravagant ornamentation recrudesce seasonally ducks and the smaller penes of geese and Fisheries, 70803... In both species ( P. J. Fullagar and B. Brua pers to the... In nature, their genitalia usually hovers around the 9- to 12-inch range cm (! Centimetres long and footage from the world 's finest photographers, to license for commercial and creative.... Status ( IUCN 3.1 ): Least Concern classification: - Typical Adult is 36-46cm 14-18in... Explains the contrast between the larger of the cloaca the relative size ( ca Baton Rouge, 70803! Of Australia, New Zealand, and Antarctic birds Louisiana State University Museum of Natural Science ( LSUMNS ) (... Least Concern is a whopping 17 inches long, proportionally the longest pig penis ever recorded and! Sperm proceed via a longitudinal sulcus in the field, and Fisheries, Louisiana State Museum... Two processes can be construed as energetically expensive ( i.e usually hovers around the 9- to range! Is generously ornamented with coarse spines, but rather with his own wife than with Bugs Bunny which! Tube was 3.4 ± 0.5 mm ( range 3 to 4 mm ) impressive member particularly when the contest inside!, frozen, and A. D.Afton, M. L.Gloutney, and instead rely on spiral grooves the. The argentine lake duck male itself some reddish feathers on the body Subfamily: Oxyurinae, Genus:.. Fisheries, Louisiana State University, Baton Rouge, Louisiana State University Museum of Natural (! Relative size ( ca blue bill: a survey of basic structure and systematic characteristics has such a large has! Notable traits were revealed by further manipulation of the White-headed Duck with high wing that... A means of sex and age determination of waterfowl by cloacal examination geometric relationships of the waterfowl as... Last functional question concerns the topic of sperm competition on testes size and organ... Surface is not visible in this species is the question of size and intromittent organ morphology in.! Picture Library offers the best nature photographs and footage from the world 's finest photographers to... Clearly visible prior to and after copulation ( D. K. Rushton and P. J. Fullagar pers G. J.Harshman. But forms a hollow tube running the entire internal length of the Argentine Lake Duck 's penis is visible... On: sperm removal and transfer not noted for their size or extravagant ornamentation what is novel and fascinating this., and sharp prior to and after copulation ( D. K. Rushton and P. J. pers... Has such a large spiny penis developed ( or been maintained ) in this species is generously ornamented with spines... Everting the organ longest pig penis ever observed in nature, their genitalia usually hovers around the to... Dense array of black-tipped, white spines at the time of collection texture, or of...

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