韩国电影爱人Pedigree strains bred towards aesthetic goals in a scientifically informed fashion...


PROMOTE THE HOBBY THROUGH OPEN MINDED EXCHANGE OF KNOWLEDGE AND IDEAS - Share your experiences as a breeder or novice both good and bad.Pass on your experiences and share results with the next generation.A successful breeder will be remembered for such efforts...

Wednesday, April 29, 2020

Skilled Vision Among Breeders

Historically, the best Pedigree Breeders always have and always will breed by eye. They are visual thinkers.  Such breeders are often very instinctive and gifted with “Skilled Vision.”

Golden Bunt Lowersword

© Alan S. Bias
Permission granted for nonprofitreproduction or duplication of photos and text with proper credit for learningpurposes only.
April 29, 2020

Skilled Vision has been loosely defined as a learned practicethat allows for recognition and productive results.  Based on powers of observation and acquiredknowledge, with far less proficiency in the language of science. 

Successful breeders possess skilled vision to varyingdegrees, and are able to develop a needed understanding of selection from handson experience.  Good practice resultsfrom recursive breedings made over time followed by evaluation of results.  Incorporating skilled vision and practice in attemptto control selection of genotype, while allowing for positive traits with reproducibleresults in future generations.  This isthe nature of Domestic Pedigree breeding.

Skilled vision can be viewed as a discipline involvingmultiple sensory inputs.  It has agenetic basis, and is not simply the result of accrued knowledge &/orenvironmental conditioning (formal education & training).  Yet, skilled vision can be enhanced throughbreeder communications, exchange of ideas, formal competitions, farm visits, breedstandards and scientific knowledge. 

Purple Body (Pb) Lowersword female
Taken as a whole, skilled vision allows a breeder to processand make sense of what is seen day to day. Breeders often lack expansive terminology to express their accruedknowledge to others.  Rather than relying on anecdotal terminology,the language of science can allow for conciseness in conversation.

Is there a dichotomy between the art of breeding and science?  Yes. While science can help a breeder understand resultsand clearly communicate them to others, extensive reliance on science inbreedings can result in a loss of “balance” in results.  This has been seen in many commercial breedsover the last several decades.

Is there dichotomy between a successful breeder and his lessor peers?  Yes.  Those with skilled vision can take breedings to optimum levels of achievement and maintain them long-term. 

Various Lowersword "Bunt" phenotypes.
Science allows me, as a breeder, to maintain a vastarray of phenotypes, with truly little effort, in a related breeding program through understanding of the sum total genotype.  Knowledge of chromatophore interactions that determine color& pattern; what is possible and what is not.

While maintaining a reference collection of nearly 5,000scientific research papers, this falls short of the visual aids I routinely relyon.  In the form or nearly 70,000 photosof guppies from personal breedings and that of others.   To this you can add another 25,000microscopy images made over the last 10 years.

My breeding notes are embarrassingly minimal andrarely referenced in day to day practice. Since childhood, sensory perception and visual analysis of the surroundingenvironment has always been my preference. Visual images often convey far more meaning than printed words.  As a result, find little need to convertimages to words in my mind.

Observation allowsfor a balance in results within my breeding program…

Grasseni, Cristina."Skilled vision. An apprenticeship in breeding aesthetics." Social Anthropology 12.1 (2004):41-55.

Grasseni, Cristina."Designer cows: The practice of cattle breeding between skill andstandardization." Society & animals 13.1 (2005): 33-50.

Grasseni, Cristina, ed. Skilled visions: Betweenapprenticeship and standards. Vol. 6. Berghahn Books, 2007.

Grasseni, Cristina. Developing skill, developingvision: practices of locality at the foot of the Alps. Vol. 3. BerghahnBooks, 2009.

Tuesday, October 16, 2018

35 Years of Breeding Blond Lowerswords

Download link for complete publication:  https://www.academia.edu/37594825/35_Years_of_Breeding_Blond_Lowerswords  English and Mandarin text.

Early Bias Blond (bb) Purple Body (PbPb)Translucent Scale (undescribed)
Lowersword (Y-Ls) circa 1985.

Current Bias Blond (bb) Lowersword (Y-Ls) 2018.

Download link for complete publication:  https://www.academia.edu/37594825/35_Years_of_Breeding_Blond_Lowerswords  English and Mandarin text.

Friday, March 31, 2017

Purple Body (Pb) study in Poecilia reticulata, an Autosomal Dominant Gene

© Alan S. Bias and Richard D. Squire
Permission granted for nonprofit reproduction or duplication of photos and text with proper credit for learning purposes only.

March 31, 2017

Homozygous Pb/Pb male

(A) Heterozygous male Pb/pb, (B) Non-Pb pb/pb male

The Purple Body gene is located on an autosome. Breeding tests, involving this modification of orange spotting, reveal this trait to have an incompletely dominant mode of inheritance. As such a formal name and nomenclature of Purple Body (Pb) has been suggested (Bias and Squire, 2017a). [Note: Hereafter Purple Gene, or Purple Body Gene used interchangeably in reference.]

Wild Poecilia reticulata, both in native populations and feral introductions, exist in a previously undocumented polymorphic state; Purple Body and non-Purple Body. In Domestic strains both polymorphisms persist as a direct result of intended breeder intervention and as an unintended result of outcrosses between fixed phenotypic strains. The co-existence of the two phenotypes suggests a selective advantage under predation (crypsis) and in sexual selection (conspicuous pattern) under diverse ambient lighting conditions.

A generally accepted definition of polymorphism states: “(1) Polymorphism is the occurrence together in the same habitat of two or more distinct forms of a species in such proportions that the rarest of them cannot be maintained by recurrent mutation. (2) If a genetically controlled form occurs in even a few percent of a population it must have been favored by selection. (3) Polymorphism may either be transient, in which a gene is in process of spreading through a population unopposed, or balanced, in which it is maintained at a fixed level by a balance of selective agencies. (4) Owing to the recurrent nature of mutation, transient polymorphism is generally due to changes in the environment, which make the effects of a previously disadvantageous gene beneficial (Ford 1945).”

The violet-blue chromatophore unit and removal of xanthophores by Pb modification is required to produce an all-purple phenotype. The Purple gene has the ability to modify extent genome-wide chromatophore populations in heterozygous and homozygous condition, with increased visibility in the UV spectrum. As a result, this demonstrates selection favoring short “private” wavelength signaling.

Pb is now identified as the first polymorphic autosomal gene to be described as existent in high frequencies in wild, feral and Domestic Guppy populations. It is capable of pleiotropic effect on all existing color and pattern elements at multiple loci. It should therefore be considered a strong candidate for further studies involving “relationships between spectral and ultra-structure characteristics” in orange ornamentation, and extending to color and/or pattern as a whole as suggested by Kottler (2014). A mechanism is identified by which Pb is capable of balancing overall color and pattern polymorphisms, in turn providing fitness through heterozygosity in diverse complex habitats.

(A) Homozygous Pb (Pb/Pb) modified ornaments, expressing removal of xanthophores and increased violet-blue iridophores. (B) Homozygous Pb (Pb/Pb) modified ornaments, expressing reduced xanthophores and increased violet-blue iridophores.(C-D) non-Pb ornaments (pb/pb) expressing no alteration of xantho-erythrophores.

The following four papers and five supplemental documents are the cumulative result of a 3 1/2 year study by Bias and Squire of the Purple Body (Pb) gene in wild, feral and Domestic strains of Poecilia reticulata.Paper No. 1 - Formal Description, No. 2 - Microscopy Tissue Study, No. 3 - Microscopy Ocular Study, No. 4 - Domestic Phenotype Expression.

Select the "Download Link" tabs below to access screened copies of documents from Cold Spring Harbor Laboratory's bioRXiv preprint server for Biology in .pdf format downloaded to academia.edu.After completion of peer review and publication links will be updated to Poeciliid Research Journal.

1. The Cellular Expression and Genetics of an Established Polymorphism in Poecilia reticulata; “Purple Body, (Pb)” is an Autosomal Dominant Gene (DownloadLink)

S1 TABLE – Condensed Breedings and Results(Download Link)
S2 TABLE – Expanded Breedings and Results(Download Link)
S3 Materials Full Description and Sources(Download Link)

Abstract. Modification of wild-type carotenoid orange and pteridine red coloration and spottingof male ornaments in both wild populations of Poecilia reticulata (Guppies) and modern Domestic Guppy strains by the Purple Body gene has long been overlooked in research articles and little understood in breeder publications. This modification is commonly found in wild-type Poecilia reticulata reticulata populations from numerous collection sites and has been photographed but not recognized in these collections. It is non-existent or near absent in collections taken from variant populations of Poecilia reticulata wingei. We identify and determine the mode of inheritance, cellular and phenotypic expression by the Purple gene in these stocks. The Purple Body color pigment modification is a distinct polymorphism in wild P. reticulata reticulata populations. Its existence suggests multiple benefits that satisfy female sexual selection preferences, and minimize or reduce potential predation risks. Photographic and microscopic evidence demonstrated that Purple Body is a normal polymorphism in wild and domestic guppies modifying color pigment regions. Purple Body is inherited as an autosomal incompletely dominant trait.

2. The Cellular Expression and Genetics of Purple Body (Pb) in Poecilia reticulata, and its Interactions with Asian Blau (Ab) and Blond (bb) under Reflected and Transmitted Light (Download Link)

S1 Materials; Slide Specimen Photos(Download Link)

Abstract. Mature Purple Body and Non-Purple Body male guppies differ from each other in several ways. Non-Purple males may have large numbers of xanthophores, erythrophores, and blue iridophores, in addition to the usual dendritic, corolla and punctate melanophores. Fewer violet iridophores are found. In contrast, homozygous Purple Body males lack collected and clustered xanthophores, although isolated single xanthophores remain. Violet iridophores and blue iridophores (violet-blue chromatophores units) abound. The dendrites of dendritic melanophores are finer and form chains with each other. Punctate and corolla melanophores in areas comprising orange ornaments are greatly reduced in number. The heterozygous Purple Body male has erythrophores similar to those of non-Purple males, but yellow pigment is reduced. The melanophores are not as greatly changed in orange ornaments. In Domestic Guppy strains, and at least in one suspected instance in wild-type, melanophore structure and populations may be further modified by one or more additional autosomal genes.

3. The Cellular Expression and Genetics of Purple Body (Pb) in the Ocular Media of the Guppy Poecilia reticulata(Download Link)

S1 Materials; Slide Specimen Photos(Download Link)

Abstract. Our study revealed the presence of all major classes of chromatophores (melanophores, xanthophores, erythrophores, violet-blue iridophores, xantho-erythrophores) and crystalline platelets in various combinations in the iris and ocular media (cornea, aqueous humor, vitreous humor, outer lens membrane) of Poecilia reticulata. This novel ocular media study of P. reticulata takes into account the distinct interactions of Purple Body (Pb) based on results of previous Bias and Squire Purple Body (Pb) publications. Taken in conjunction with other researcher’s published results (regarding UV reflected color and pattern, vision, mate choice, individual preferences, and opsin capabilities) this indicates that these ocular chromatophore populations together create a complex ocular filter mechanism. This mechanism in turn provides spectral capabilities into the UV and Near-UV wavelengths in both Pb and non-Pb individuals. The chromatophores in the cornea, aqueous humor, covering membranes of the lens, and the vitreous humor comprise an ocular filter system that could reduce UV damage to the internal structures of the eye. The guppy’s ability to use UVA as a visual component provides a “private signally system” that cannot be detected by some predators. While non-Pb guppies should derive benefit in the near-UV from violet-blue iridophore units, greater benefit will be derived by Pb individuals with more violet iridophores functioning in the lower UV and near-UV wavelengths. To our knowledge little has been published for P. reticulata concerning pigmentation within the guppy eye. Macroscopic and microscopic imagery is presented.

4. The Phenotypic Expression of Purple Body (Pb) in Domestic Guppy Strains of Poecilia reticulata(Download Link)

Abstract. Modification of wild-type carotenoid orange and pteridine red coloration and spotting of male ornaments in modern Domestic Guppy Strains (Poecilia reticulata reticulata) by the naturally occurring Purple Body gene (Pb) has been long incorporated into their strains by Pedigree Stock Breeders. It is inherited as an autosomal incompletely dominant trait. Its existence has allowed breeders to produce a vast array of Purple based phenotypes. Photographic evidence demonstrates that Purple Body is a normal polymorphism in domestic guppies modifying color pigmented regions. When combined with currently used mutant genes such as Albino, Blond, Golden, Asian Blau, Coral Red, Magenta, Grass, Moscow, Pink, Platinum, Red Mosaic, Multicolor, and Full Red, startling new phenotypes are created. The recently described Purple Body gene (Bias and Squire 2017a, 2017b, and 2017c) has long been overlooked in research articles and little understood in breeder publications.

IFGA Purple Delta, photo courtesy of Terry Aley

Saturday, February 18, 2017

Jemez Feral Guppies; McCauley Springs, New Mexico

Jemezferal male

© Alan S. Bias – Feb. 17,  2017
Permission granted for nonprofitreproduction or duplication of photos and text in entirety with proper creditfor learning purposes only.

NOTE:  All photos by author or Tom Coggins with express permission.

Nestled high in the Jemez Mountainsof Sandoval County, New Mexico, at an elevation of around 7350’ (2240.28meters) reside one of the most unique and oldest established feral populationsof Poecilia reticulata in North America. This self-sustaining population is not only a jewel for livebearerenthusiast tanks, but the focus of much formally published research.  As with most thermal spring environmentsthroughout the United States, conditions can be rather harsh for a speciesevolved in a tropical setting.  Overall, size of habitable range isnormally limited by temperature extremes, predation, and water chemistry to thefirst few pools near issuing thermal source. In others habitation will extend downstream to a point where minimumsurvivable temperatures are no longer maintained during winter extremes.  

While published research indicates a stocking date ca. 1975or before of “feeder Guppies”, Jemez has varying sources suggesting initialdates of introduction ranging from the late 1940's - 1960's.   Thiscoincides with most North American feral populations. Based on known genotypeand phenotypical expressions, the Jemez population is unique in that individualsexpress little indication of founding members deriving from modern DomesticGuppy strains.  While likely notwild-caught, they show little in the way of domestication.  Since their introduction having evolved intoan interesting study population for researchers and breeders alike.

Jemezferal male

Priorpublished testing U.S. Geological Survey at McCauley Springs revealed a thermaldischarge rate of between 310 - 400 gpm. The same study indicated an average discharge temperature of between30.6 - 31.6*C.  Specific Conductanceranged between 160 - 180 S/cm.

Analysisof tritium levels at McCauley Springs were indicative of water entering theground prior to 1953, though also suggestive of some water entering post thisdate.  Water is circulated in the upper1500’ of the ancient Valles Caldera moat and heated by geothermal heat fluxcommon in the region.  While many springsin the regions are much hotter, McCauley is generally considered a “WarmSpring”, with dilution in ground water supply, having a pH of 8.0 andcorresponding lower levels of most minerals.

My Jemez studypopulation derive from a large collection of individuals on July 15, 2016.  Guppyhabitation was limited primarily to the first two pools after thermaldischarge. Greater numbers of Poecilia reticulata and Gambusia geserei residein the first pool, as compared to the second. Average depth of poos was around3 feet at center with shallow edges.  Waterleaving the McCauley Spring Stream flows into the East Jemez River, before enteringthe Jemez River proper.  Watertemperature on the date of collection was just over 32.2*C at spring source,with slightly varying pH readings of 8.0+. Water temperature in the first habitable pool was over 31.1*C, with anoticeable drop in the second pool.    Eachpool was strewn with sand and rock of varying size.  An abundance of plant growth resembling NajaGrass (Najas guadalupensis) and algae was present in the first pool, while lowerpools lacked vegetation.

The indicated pool temperature isconsidered within “habitable range” for Poecilia reticulata, though it isnearing the upper maximum limit.  Extremelimit need not be “lethal” in immediate fashion to result in long-termrepercussions.  Male guppies have beendemonstrated to have preference for slightly lower temperatures (24.5*C) vs.females (28.2*C) for optimal development of secondary sexual characters; in theform of color ornaments and gonopodia. Lower temperatures can result in delayed maturation, and highertemperatures in deformity.  Furtherstudies support a reduction in overall body mass, growth, reproduction andlocomotion, in both sexes, for individuals reared long-term in temperatures inexcess of 30*C.

McCauleySprings pool, photo courtesy of Tom Coggins

Just as temperature restricts theseferal populations, so does predation.  At McCauley predation in the firsttwo pools is limited to resident non-native Gambusia geserei, birds,crustaceans, and insects.    Thepresence of Gambusia affinis in other locations is known to greatly restrictferal juvenile Guppy population levels.  Nativespecies of Rio Grande Sucker, Longnose Dace and Flathead minnow are found in theEast Fork of the Jemez River, well below the restricted Poecilia reticulatazone of habitation.

Collected fishshowed no signs of parasitic infestation, nor have subsequent captiveraised.  This population may still retain genetic predisposition forresistance.  Further benefit is derived inthe form of constant high water temperature beyond 28.9*C, which is lethal toIchthyobodo necator (Costia).  Individuals pretty much match descriptionsof published research by Nicoletto & Kodric-Brown (See: Scientific Study Excerpts).  Overall individuals are veryreflective with minimal ornamental orange spotting in those collected, and F1offspring.

Jemezferal male foraging

Captive bred F2and F3 show an expected increase in both red and yellow color ornaments in males,when reared with no predation.  Spottingremains very distinct, with circular patches surrounded by iridophore /leucophores circular rings.  Also, notedis an increase in upper and lower sword ornaments with minimal extension.
Nearly allcollected males and offspring are hyaline dorsal.  Some express blackmelanophores in the dorsal, but not the O. Winge trait known as Maculatus. The majority of males express basic wild-type oval-tail, a percentage small top-swordwith minimal extension, and the remainder rudimentary flag-tails.  A very reflective iridophore ring surroundsprimary ectopic melanophore “eye spots” in the anterior body.  Violet-blueiridophore pattern is present, in nearly all males in the body, to include longlinear patches.
Jemezferal male

Potential extreme temperature issuesmanifest in two forms in collected individuals: size and shape.  Size reduction isevident both sexes collected at McCauley Springs.  However, this condition did not completelymanifest in F1 offspring reared under cooler temperatures.  Males and females showed dramatic increase insize under optimum temperature and feeding regimen.  Though size disparity remained between thesexes, with females expressing a proportionally larger increase in overallsize. 

A high percentageof collected females expressed little or no tapering of posterior peduncle,likely as a result of high environmental temperatures in the first pool. This “thickness” has alleviated somewhat in captive raised fish, though in generalthickness in female body form is much greater than many wild or captive bredpopulations.  Males in turn, havedemonstrated just the opposite. Collected males demonstrate a “linear and lanky” appearance, despite lowvelocity water conditions.  Captivereared, to a high degree, are much more robust in body type.  In general, the overall body size has increasedand lengthened in both males and females.

JemezSprings feral male

All fish appearto be heterozygous or homozygous Purple Body Mutation (Pb).  Lifespan appears longerthan some feral populations I have worked with, and consistent with others.  Research indicates they have evolved overmultiple generations under limited predation on a diet consisting mostly ofalgae.  Jemez males phenotypically resemblethe Kemp 2008 Quare study population in many ways, and likely demonstrate thesame fairly low UV peaks.  Melanophore ornaments are both circular andlinear, with the latter more predominant.  Good fertility is evident, withmoderate size litters of 15-30 fry.  Based on breeding results thispopulation shows little, if any, sign of additional infusion from other sourcessince initial stocking(s).  All research papers seem hesitant to citestocking date earlier than late 1960-70’s.  From what I have informallygathered and observed, it seems likely an earlier stocking date is more than plausible.

A percentage ofmales express Iridescens (Ir); “reflective dorsal spot”.  This in itself issuggestive of a much earlier stocking date.  Ir was present in earlybreeder tanks 1920-40’s and prior to modern collections of Poecilia reticulatawingei (to include those known as Endler’s Livebearer).

IridescentMale with Reflective Dorsal Spot

All females arecolor tail / neutral oval-tail, with the exception of limited purple-blueiridophores (Pb expression) &/or yellow xanthophore in the form of Flavis (Fla) in the caudal base. Females express much in the way of reflective qualities, as found inmales, as compared to many other feral populations or wild populations.   Including purple-blue iridophores, heavyreticulation, and black striping on anterior shoulders along the lateral line. This is suggestive of “overall” Jemez reflectivity stemming from X-link&/or autosomal modes of inheritance. Population appears homozygous grey, in wild caught and in captive bredto date.
Jemezferal females

Surprisingly, this population doesnot exhibit a very high "fright or flight" response to human trafficor movement from above, and is known for gathering around bathers entering thepools in large schools.  Under hightemperature parameters this increased mobility may be indicative of lowpredation levels on adults (Gambusia geserei predation limited to juveniles)&/or low satiation levels (limited food resources in small area ofhabitation) for the group constituents as a whole.  Collected individuals easily settle intocaptivity in uncovered tanks with high water levels.  Readily respond to feeding, and unlikePoecilia reticulata wingei variants, take little notice during tankmaintenance.  Though interestingly, whenremoved and confined to small tanks during photography, males expressing nearwild-type color ornaments exhibit higher levels of agitation and continuousmovement, as opposed to those expressing increased color / pattern arising fromlack of predation in captive rearing.
Jemezferal males

Kodric-Brown (1989) utilized 2 study populations, Paria wild [Trinidadian]and Jemez feral [McCauley Springs, NM].  McCauley Springs feralexpress reduced orange spotting in comparison to other populations.  Notsurprisingly, it was reported “Females from the Jemez population showedsignificant disagreement in their preferences for individual males.”  Jemez males exhibit increased iridophore spotting (blue and white), andincreased circular and linear melanophore spots.  Jemez males are veryiridescent purple-blue, often expressing: Iridescens (Ir), (Winge 1922b;See also:  Iridscens (Ir), Blacher 1928; SmargdIridescens (SmIr), Dzwillo 1959; Blue Iridescent Spot, Kottler2013; Reflective Dorsal Spot (RDS), Bias 2013).

The wild type guppies used in this study were from a thirdgeneration laboratory colony derived from a feral population located in theMcCauley hot spring in the Jemez Mountains of New Mexico. This population hasbeen there for at least 16 years (R. Thorn-hill, personal communication). Allfish appeared to be in good physical condition. The three male tail types usedwere upper sword, flag, and round... …These three tail types are common in theMcCauley springs population (personal observation). (Nicoletto 1991).

Offspring reared in the laboratory encountered differentenvironmental conditions from their field-caught sires. A laboratoryenvironment, with its abundant food and constant conditions, may have permittedthe expression of ornaments in male offspring that were present, but notexpressed, in field-caught sires…  …In other words, in the laboratoryenvironment we may find an uncoupling of ornamentation and constitution, sodifferences in the ornamentation of offspring of different sire types were notobserved. The uncoupling argument may also explain why the offspring ofpreferred males were not more ornamented than the offspring of non-preferredmales as both the Fisherian and adaptive models predict.  (Nicoletto 1995)

In this study, the field-caught sires had significantly fewerorange spots with less relative area than their laboratory reared sons… …and the heritability estimate for orange was not significantly different fromzero, indicating little or no heritability. This suggests that the sires mayhave been unable to express their orange ornamentation because of adverseenvironmental conditions. The environment of the Jemez Mountain sires is highlyoligotrophic and the fish feed primarily on algae. I examined the gut contentsof 27 guppies in 1987 from the Jemez population and found all to contain algae,and only one large female contained a single unidentified insect. Although nothing is known about the development of orange ornamentation inguppies reared exclusively on a diet of algae, they are known to have slowergrowth rates than guppies fed Daphnia or Tetramin (Dussault & Kramer 1981). (Nicoletto 1995)

Guppies used in this study were the laboratory-born offspring offield-caught guppies from a feral population located in McCauley Hot Spring inthe Jemez Mountains of New Mexico.  This population has lived in thespring for at least 23 years (Koster W, personal communication). These fish aredescendants of domesticated "feeder guppies" that are somewhatsimilar in appearance to wild-type guppies (Nicoletto, 1993), but they areprobably not as variable (Endler JA, personal communication).  (Nicoletto 1996)

Jemez males had significantly more iridescent coloration (x =29.6%, SE= 11.40) than Trinidad males (x = 4.380, SE = 4.45). Jemez males alsohad two types of iridescent spots, blue and white, whereas Trinidad males onlyhad white spots. There were no significant differences between Trinidad andJemez males for the percent of their bodies covered with orange or black colorspots... Both Trinidad and Jemez females preferred males with high displayrates, but differed in the relative visually-preferred males. (Kodric-Brown 1996)

Jemez females preferred males with larger areas of carotenoidspots, and pattern complex-ity. Female choice of males with complex colorpatterns may, in part, explain the high degree of disagreement among the Jemezfemales in their choices of males. However, complexity of the color pattern didnot seem to be an important factor in the PCA analy-sis. (Kodric-Brown 1996)

Guppies used in these experiments were descendants from a feralpopulation in McCauley Hot Spring in the Jemez Mountains of New Mexico. Thispopulation has lived in the spring for at least 24 years. These fish aredescendants of ‘feeder guppies’ that are similar in appearance to wild-typeguppies, although they may be more variable in their mate preferences(Nicoletto 1993, Kodric-Brown & Nicoletto 1996).  Mating preferencesof this population have been extensively studied. Females differentiallyrespond to males with high display rates (Nicoletto 1993) and to displays oflonger duration (Nicoletto 1996). Jemez females also respond preferentially tomales with more complex ornamentation and more orange color on their body(Nicoletto 1993). However, courtship vigor is correlated with carotenoidpigmentation, and when the variance in display rate is statistically controlledthe preference for males with more orange color disappears.  In thisrespect Jemez guppies differ from other guppy populations (Endler 1980, 1983,Endler & Houde 1995, Houde 1987, 1988, Kodric-Brown 1985, 1989). (Nicoletto & Kodric-Brown 1999)

Jemez males also have extensive iridescent ornamentation. The role of these iridescent colors in mate choice is unknown. They mayfunction in long-distance attraction of females (Endler 1983). In this studyfemales did not respond to differences in the blue treatment, and this isconsistent with some previous studies using live males (Nicoletto 1993, 1995).However, in a study of mate preferences by Kodric-Brown & Nicoletto (1996)a Principal Component analysis showed that some females in this populationpreferentially responded to males with extensive iridescent ornamentation.Iridescent blue and/or violet coloration also seems to be an importantcriterion in mate choice of several populations of Trinidadian guppies (Endler& Houde 1995). (Nicoletto& Kodric-Brown 1999)

Fish used in our experiments were laboratory-reared, firstgeneration descendants of females caught at McCauley Spring in the JemezMountains near Albuquerque, New Mexico. The population was established byintroduction approximately 30 yrs previously. It experiences low predationpressure, since there are no piscivorous fish. Males are highly ornamented,with large areas of the body and fins covered with red and yellow (carotenoid),black (melanin), and iridescent (mostly blue and white) spots. Females prefermales with complex color patterns, large areas of carotenoid pigment, and highdisplay rates (Nicoletto 1993, 1995). (Kodric-Brown 2001)

Jemez females mature much later than females from Trinidadianpopulations that experience low predation and high adult survivorship.Typically, less than half of the Jemez females mated to males at 3–4 months oldproduced broods, whereas females from Trinidad were fully sexually mature atthat age (Reznick et al. 1996). We chose 6-mo-old females because at that ageall are mature and can produce a brood. At 12 mo, all Jemez females are stillreproductively active. In the laboratory, Jemez females senesce and begin todie at an age of 18–24 mo. Senescence is characterized by smaller brood size orcessation of reproduction.  Although we have no information about the ageof females in Jemez Springs, gravid females of the size class of ourlaboratory-reared 12-mo-old females are quite numerous.  (Kodric-Brown 2001)

Age had a significant effect on female responsiveness to theshowy male image. Six-month-old virgin females spent significantly more timeviewing the image of the showy male than 12-mo-old virgin females. A greaternumber of females preferred the showy male at the age of 6 mo[nths] than at 12 mo[nths] orafter mating and producing a brood... Thus, female preference for showy malesdecreased with age. Mating experience had no effect on the responses of femalesto showy males. Twelve-month-old virgin females and postpartum females spentapproximately equal amounts of time viewing both showy and plain males.  (Kodric-Brown2001)

Our results document changes in female responsiveness based onone criterion, male ornamentation, specifically the area of carotenoid spots.The intensity and size of carotenoid spots are important criteria for femalechoice in all populations of guppies examined to date, including laboratorystocks (e.g., Farr 1980; Kodric-Brown 1993), naturalized populations (e.g.,Nicoletto 1993; Brooks and Caithness 1995), and native populations in Trinidad(e.g., Endler and Houde 1995). However, our results should not be taken toimply that older females are incapable of discriminating among males and do notshow preferences for particular male traits. Because we tested only the area ofcarotenoid spots, we cannot rule out mate choice based on other criteria, suchas other pigment patterns or courtship displays. Females from the Jemezpopulation do show strong preferences for vigorously displaying males(Nicoletto 1993, 1995). So older females may well select males based primarilyon the vigor and duration of courtship displays rather than carotenoidpigments…  Our results have important implications for studies of sexual selection. They suggest that criteria for mate choice may change withfemale age, thus altering selection for multiple male secondary sexual traits,including male courtship tactics. If older females are less responsive to malemorphological traits, such as carotenoid color spots, then males mightcompensate in their courtship tactics and engage in more vigorous displays.Indeed, male guppies have been reported to increase their courtship displays towardlarger, and presumably older, females (Baerends et al. 1955; Houde 1997).  (Kodric-Brown 2001)

When females were presented with 'mixed signals,' namely dullmales courting intensely, and males with orange coloration and low levels ofcourtship, there was no significant difference in the time they spent with eachimage, because females varied in their preferences for each image. Theseresults are consistent with the interpretation that the dynamic (courtshipdisplay) and the static signals (orange color) are equally attractive. Ourresults also support an alternative interpretation, namely that females of thispopulation show individual preferences in the relative ranking of these twotraits: some may show a preference for orange color, while others may basetheir preference on display rate. The observed patterns are also consistentwith those found in a previous study of Jemez guppies using live males, wherefemales differed in their preferences for male ornaments (carotenoid andiridescent spots (Kodric-Brown and Nicoletto 1996). (Kodric-Brown 2001)

To determine whether predation pressure affects femalepreference for males with UV-reflective colour patterns, we compared theresponses of Jemez females with those of Quare females. The Jemez females werefrom a population of naturalized guppies in McCauley spring located in theJemez Mountains of New Mexico, U.S.A. The Jemez population was introduced intothe spring over 30 years ago, and since then has had no piscivorouspredators.  (Kodric-Brown2001)

Male UV Reflectance Patterns Colour patterns of Jemez males showed UV-reflective components thatcovered 4–31% of the body area. Most, but not all, of the iridescent coloursalso reflected below 400 nm (near UV and UV). Among the iridescent colours,white and purple strongly reflected below 400 nm, but green and blue did not.Gold (yellow–orange) also showed a UV component. Generally, the area of UVreflectance closely matched the area of iridescence visible in longerwavelengths. Although the overall colour pattern was the same when viewed inthe visible and the short wavelengths, certain aspects of the pattern were morenoticeable in the UV wavelengths. Melanin (black) spots surrounded, eithercompletely or partially, by a ring of iridescent white, and gold spots next toblack areas provided a striking contrast in the UV.  (Kodric-Brown 2001

Jemez females Responses to male pairs matched for all colours.  Females spent almost twice as longobserving a male behind the UVT partition as they did the same male viewedbehind the UVB partition. These results suggest that females not only respondto the UV-reflective components of the male colour patterns, but that thesecomponents contribute to the overall attractiveness of a male. Responsesto male pairs differing in UV reflectance area. Females, when given achoice between pairs of males that were matched for carotenoids and iridescencebut differed in UV reflectance, consistently chose the male of the pair behindthe UVT partition. Difference in the time females spent with the moreornamented male of the pair was positively correlated with the difference inthe area of UV reflectance between the pairs. These results indicate thatfemales respond to the area of a male’s colour pattern that reflects UVwavelengths.  Responses to male pairs differing in carotenoidarea. There was no effect of treatment (UVT versus UVB) on femaleresponses to male pairs that differed in the area of carotenoids but werematched for area of iridescence and UV reflectance.  Similarly, there wasno positive correlation between the time females spent with the more ornamentedmale of the pair when he was behind the UVT partition. Jemez femalesResponses to the UV-reflective components of male colour patterns. Femalesfrom both populations spent longer viewing males when the males were placedbehind the UVT partition than when the same males were placed behind the UVBpartition. Jemez and Quare females responded in a similar way to manipulationsof the UV-reflective component of male colour patterns.  Predation levelthus does not seem to affect female responses to UV-reflective components ofmale colour patterns.  (Kodric-Brown 2001).

Jemez FeralGuppies continue to offer researchers an ongoing opportunity to study anevolving population within the confines of North America.  They also offer breeders a unique set of“genetic tools” for use in Domestic breeding programs.

My initial testoutcrosses are only in early stages. Yet, based on observations of my ½ dozen feral breeding colonies a hostof potential benefits are possible in outcross offspring for color, pattern andreflection.  It is rare for breeders to identifya breeding population or strain of Poecilia reticulata with the reflectivequalities and pattern expression exhibited in Jemez, outside of selectivelybred Swordtail strains or from infusions of P. reticulata wingei variants.  While published research as quantified Jemezornamental traits along scientific standards, little has been documented alongbreeder recognized traits and mode of inheritance.

Many thanks to my friend, and fellowcollector / breeder Tom Coggins (Missouri) for this recent collection. Tom went out of his way to not only make this collection in New Mexico,but deliver them in entirety two weeks later at my Southern WV home.  

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Gillooly, J. F., Brown,J. H., West, G. B., Savage, V. M., & Charnov, E. L. (2001). Effects of sizeand temperature on metabolic rate. science, 293(5538), 2248-2251.

Johansen, P. H., &Cross, J. A. (1980). Effects of sexual maturation and sex steroid hormonetreatment on the temperature preference of the guppy, Poecilia reticulata(Peters). Canadian Journal ofZoology, 58(4),586-588.
Kodric-Brown, A., &Nicoletto, P. F. (1996). Consensus among females in their choice of males inthe guppy Poecilia reticulata. BehavioralEcology and Sociobiology, 39(6),395-400.

KodricBrown,Astrid, and Paul F. Nicoletto. "Age and experience affect female choice inthe guppy (Poecilia reticulata)." TheAmerican Naturalist 157.3(2001): 316-323.

Kodric-Brown,A., & Nicoletto, P. F. (2001). Female choice in the guppy (Poeciliareticulata): the interaction between male color and display. Behavioral Ecology and Sociobiology, 50(4), 346-351.

Kodric-Brown,A., & Johnson, S. C. (2002). Ultraviolet reflectance patterns of maleguppies enhance their attractiveness to females. Animal Behaviour, 63(2), 391-396.

Kodric-Brown, A., &Johnson, S. C. (2002). Ultraviolet reflectance patterns of male guppies enhancetheir attractiveness to females. AnimalBehaviour, 63(2),391-396.

Mu?oz, N. J., Breckels,R. D., & Neff, B. D. (2012). The metabolic, locomotor and sex-dependenteffects of elevated temperature on Trinidadian guppies: limited capacity foracclimation. Journal ofExperimental Biology, 215(19),3436-3441.

Nicoletto,P. F. (1993). Female sexual response to condition-dependent ornaments in theguppy, Poecilia reticulata. AnimalBehaviour, 46(3),441-450.

Nicoletto, P. F. (1995). Offspring quality and female choicein the guppy, Poecilia reticulata. AnimalBehaviour, 49(2),377-387.

Nicoletto, P. F. (1996). The influence of watervelocity on the display behavior of male guppies, Poecilia reticulata. Behavioral Ecology, 7(3), 272-278.

Sublette, E. J., Hatch, D. M., & Sublette, M. (1990). The fishes of New Mexico.University of New Mexico Press.

Trainer, F. W., Rogers, R. J., & Sorey, M. L. (2000). Geothermal Hydrology of VallesCaldera and the Southwestern Jemez Mountains, New Mexico (No. 2000-4067). US Department of theInterior, US Geological Survey; Information Services [distributor]

USDA 2002, East ForkJemez Wild and Scenic River Management Plan, US Dept. of Agriculture, ForestService.  Jemez Ranger Dist., Santa FeNational Fores, Sandoval County, New Mexico.

WEETMAN,D., ATKINSON, D., & CHUBB, J. C. (1999). Water temperature influences theshoaling decisions of guppies, Poecilia reticulata, under predation threat. Animal behaviour, 58(4), 735-741.

Show seasons around the world are getting ready to kick off.  Support them with your entries.
Make some time to attend one.  Great chance to meet some breeders in person...


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