Male coloration affects female gestation period and timing of fertilization in the guppy (Poecilia reticulata)

The trade-up hypothesis is a female behavioral strategy related to mating with multiple males. In this hypothesis, females can produce high-quality offspring while avoiding the risk of losing reproductive opportunities by non-selective mating with males at first mating and then re-mating with more attractive males. As an internal mechanism to realize this behavioral strategy, we predicted that females would immediately fertilize their eggs when they mated with attractive males, whereas females would delay fertilization when they mated with unattractive males to trade-up sires of offspring. The guppy (Poecilia reticulata) is an ovoviviparous fish with internal fertilization, and females show a clear mate preference based on the area of orange coloration on the bodies of males. In addition, it is known that females show a re-mating strategy consistent with the trade-up hypothesis. We tested whether the attractiveness of mated males affected the gestation period and the timing of fertilization. Females were paired with either colorful males or drab males, and the gestation periods (the number of days from mating to parturition) were compared. In addition, we dissected the abdomens of the females at intervals of several days after mating and observed whether the eggs were fertilized. The gestation period in females that were paired with attractive colorful males was significantly shorter than that in females that were paired with drab males. We found that females that mated with colorful males also had their eggs fertilized earlier than those that mated with drab males. Our findings show that differences in the timing of fertilization according to attractiveness of the mate increase the opportunity for cryptic female choice and trading up.

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Social Behavior Patterns as Determinants of Reproductive Success in the Guppy, Poecilia Reticulata Peters (Pisces: Poeciliidae) an Experimental Study of the Effects of Intermale Competition, Female Choice, and Sexual Selection

Behaviour ◽

10.1163/156853980x00311 ◽

1980 ◽

Vol 74 (1-2) ◽

pp. 38-90 ◽

Cited By ~ 123

Author(s):

James A. Farr

Keyword(s):

Sexual Selection ◽

Social Behavior ◽

Reproductive Success ◽

Female Choice ◽

Poecilia Reticulata ◽

Ecological Niches ◽

Color Patterns ◽

Courtship Display ◽

Male Effect ◽

Male Coloration

AbstractThe reproductive success of competing male guppies, Poecilia reticulata, was measured and compared to various features of social behavior and secondary sexual coloration. The most important determinant of reproductive success was the rate at which a male courted females relative to those of other males. Males with higher display rates have a greater chance of encountering a receptive female and are preferred by females. Males adjust their display rate in such a way as to be just noticeably more active than a competitor, and inbred strains differ in the maximum rate at which males can court females. No other factor is able to offset the disadvantage of displaying at a relatively low rate. Sexual selection has resulted in the maximization of courtship activity in natural populations. If males court females with equal frequencies, those which also inseminate females through gonopodial thrusting without female cooperation have a selective advantage. Because poeciliid females store sperm, inseminations through gonopodial thrusting can reduce the reproductive success of competitor males which copulate only following a display. A mixed strategy of displaying and gonopodial thrusting is more successful than either pure strategy. The result is a mating system which partially ignores female choice mechanisms. Intermale aggresssion was found to be maladaptive. Males which displayed at higher rates than competitors were less successful if they were also more aggressive than the competitors, than when they were non-aggressive or the competitors were more aggressive. Males were not able to reduce a competitor's courtship display rate through aggression. It was hypothesized that the low level of aggression in natural guppy populations is attributable to the fact that variance in size of males is low and fights would be lengthy before a winner could be determined. This would subtract from time available for courtship, and female preference for high-displaying males would select against aggressive phenotypes. There was little evidence that conspicuousness of male coloration influences female choice of males. Dull males with high courtship display rates were significantly more successful than conspicuous males with low display rates. It was concluded that females prefer conspicuous males only if all males exhibit equal courtship display rates. The frequency of male color patterns in a population did affect reproductive success. Males with rare color patterns sired more offspring than expected given their frequency. The mechanism by which a rare male effect was achieved depended on the relative mating success of phenotypes in control populations (all phenotypes occurring with equal frequency). If a normally preferred phenotype was rare, females continued to prefer that phenotype over the common phenotype. If a normally unpreferred phenotype was rare, females mated with that phenotype in addition to the preferred phenotype, and the rare male effect was thus achieved by multiple inseminations. Females also tended to mate with more than one male in polymorphic populations, and it was concluded that certain female choice patterns with frequent multiple inseminations can maintain a polymorphism in addition to a pure rare male effect. It was hypothesized that courtship displays and conspicuous male coloration are sexually selected characters which evolved in response to the occupation of invariable habitats or specialized ecological niches by a sexually monomorphic ancestor with only gonopodial thrusting as a means of inseminating females. A subsequent reinvasion of variable habitats resulted in female choice mechanisms which maximize the level of heterozygosity of their offspring, thus resulting in polymorphic populations. The coloration of male guppies is a phenotypic cue which influences female choice in such a manner that they mate with those males with whom they most probably have the fewest genes in common.

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Offspring quality and female choice in the guppy,Poecilia reticulata

Animal Behaviour ◽

10.1006/anbe.1995.0050 ◽

1995 ◽

Vol 49 (2) ◽

pp. 377-387 ◽

Cited By ~ 48

Author(s):

PAUL F. NICOLETTO

Keyword(s):

Female Choice ◽

Poecilia Reticulata ◽

Offspring Quality

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Amplifiers and the origin of animal signals

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2016.0324 ◽

2016 ◽

Vol 283 (1832) ◽

pp. 20160324 ◽

Cited By ~ 7

Author(s):

Laurens Bogaardt ◽

Rufus A. Johnstone

Keyword(s):

Signal Detection ◽

Female Choice ◽

Signal Detection Theory ◽

Animal Communication ◽

Detection Theory ◽

Direct Selection ◽

Simple Explanation ◽

Male Quality ◽

High Quality ◽

Selection For

In 1989, Hasson introduced the concept of an ‘amplifier’ within animal communication. This display reduces errors in the assessment of traits for which there is direct selection and renders differences in quality among animals more obvious. Amplifiers can evolve to fixation via the benefit they confer on high-quality animals. However, they also impose a cost on low-quality animals by revealing their lower quality, potentially leading these to refrain from amplifying. Hence, it was suggested that, if the level of amplification correlates with quality, direct choice for the amplifying display might emerge. Using the framework of signal detection theory, this article shows that, if the use of an amplifier is observable, direct choice for the amplifying display can indeed evolve. Consequently, low-quality animals may choose to amplify to some extent as well, even though this reveals their lower quality. In effect, the amplifier evolves to become a signal in its own right. We show that, as amplifiers can evolve without direct female choice and are likely to become correlated with male quality, selection for quality-dependent amplification provides a simple explanation for the origin of reliable signals in the absence of pre-existing preferences.

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Familiarity leads to female mate preference for novel males in the guppy, Poecilia reticulata

Animal Behaviour ◽

10.1006/anbe.1999.1225 ◽

1999 ◽

Vol 58 (4) ◽

pp. 907-916 ◽

Cited By ~ 192

Author(s):

KIMBERLY A. HUGHES ◽

LINH DU ◽

F.HELEN RODD ◽

DAVID N. REZNICK

Keyword(s):

Poecilia Reticulata ◽

Mate Preference ◽

Female Mate Preference ◽

Female Mate

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A Construction of Fault Test Constraint Based on the Optimal Fusion Set of Multiple Slices

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.774-776.1604 ◽

2013 ◽

Vol 774-776 ◽

pp. 1604-1608

Author(s):

Yi Zhang ◽

Gang Wang ◽

Ping Rong Lin

Keyword(s):

Weight Coefficient ◽

Test Case ◽

Random Testing ◽

Quality Test ◽

High Quality ◽

Estimation Formula ◽

Internal Mechanism ◽

Optimal Fusion ◽

Software Fault ◽

Case Design

The standard program slicing of different slices is put into the fusion matrix of the optimal fusion to measure the consistent fusion of slices. In the biopsy of the actual fusion process, the slicing techniques with high consistent fusion and balanced fusion distribution are used to reasonably allocate each weight coefficient, and thus the final fusion estimation formula is obtained. We use slice fusion, path conditions, as well as the internal mechanism of software fault trigger and propagation, to construct the test constraint of a fault. It can help to direct high quality test case design and to evaluate the applicability of the adaptive random testing.

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