Reproductive Isolation and the Potential for Character Displacement in the Damselflies, Calopteryx maculata and C. aequabilis (Odonata: Calopterygidae)

1975 ◽  
Vol 24 (1) ◽  
pp. 24 ◽  
Author(s):  
Jonathan K. Waage
Keyword(s):  
Reproductive Isolation ◽  
Character Displacement ◽  
Calopteryx Maculata

Evolution of Flowers, Pollination, and Plant Diversity

2011 ◽  
Author(s):  
Pat Willmer
Keyword(s):  
Reproductive Isolation ◽  
Genetic Drift ◽  
Plant Diversity ◽  
Character Displacement ◽  
Good Evidence ◽  
Early Evolution ◽  
Evolutionary Divergence ◽  
Floral Variation ◽  
Character Correlations ◽  
Animal Pollination

This chapter examines the evolution of flowers, pollination, and plant diversity. There is good evidence for pollinator-mediated selection and appropriate trait heritability in flowers, and there are well-established mechanisms by which this could bring about floral change, reproductive isolation, and evolutionary divergence or specialization. The chapter first considers the origin and early evolution of flowers before discussing the diversification of angiosperms. It then explores the advantages of animal pollination and goes on to discuss the extent to which pollination may have contributed to floral variation, plant speciation, and plant diversification. In particular, it explains whether pollinators select for floral divergence and describes five ways in which floral divergence could arise by selection: adaptation to distinct niches, character displacement, adaptive “wandering,” character correlations, and genetic drift.

No character displacement for reproductive isolation between Drosophila bipectinata and Drosophila malerkotliana

Genome ◽  
1991 ◽  
Vol 34 (6) ◽  
pp. 849-852 ◽  
Author(s):  
B. N. Singh ◽  
Sujata Chatterjee
Keyword(s):  
Reproductive Isolation ◽  
Sexual Isolation ◽  
Character Displacement ◽  
Sympatric Populations ◽  
Allopatric Populations ◽  
Drosophila Bipectinata ◽  
Isolation Index ◽  
Drosophila Malerkotliana

To test whether character displacement for reproductive isolation between Drosophila bipectinata and Drosophila malerkotliana exists, the degree of sexual isolation was measured between their sympatric and allopatric populations. Although the isolation indices vary in different crosses, the average isolation index for sympatric populations is very close to that for allopatric populations. This shows no difference in the degree of sexual isolation between sympatric and allopatric populations of D. bipectinata and D. malerkotliana. Thus there is no evidence for the existence of character displacement for sexual isolation between these two closely related sympatric species.Key words: Drosophila bipectinata, Drosophila malerkotliana, sexual isolation, sympatric and allopatric populations.

scholarly journals Reproductive character displacement generates reproductive isolation among conspecific populations: an artificial neural network study

2006 ◽  
Vol 273 (1592) ◽  
pp. 1361-1368 ◽  
Author(s):  
Karin S Pfennig ◽  
Michael J Ryan
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Artificial Neural Network ◽  
Artificial Neural Networks ◽  
Reproductive Isolation ◽  
Mate Recognition ◽  
Character Displacement ◽  
Reproductive Character Displacement ◽  
Reproductive Character ◽  
Artificial Neural

When interactions with heterospecifics prevent females from identifying conspecific mates, natural selection can promote the evolution of mating behaviours that minimize such interactions. Consequently, mating behaviours may diverge among conspecific populations in sympatry and in allopatry with heterospecifics. This divergence in conspecific mating behaviours—reproductive character displacement—can initiate speciation if mating behaviours become so divergent as to generate reproductive isolation between sympatric and allopatric conspecifics. We tested these ideas by using artificial neural networks to simulate the evolution of conspecific mate recognition in populations sympatric and allopatric with different heterospecifics. We found that advertisement calls diverged among the different conspecific populations. Consequently, networks strongly preferred calls from their own population to those from foreign conspecific populations. Thus, reproductive character displacement may promote reproductive isolation and, ultimately, speciation among conspecific populations.

scholarly journals Continental variation in wing pigmentation in Calopteryx damselflies is related to the presence of heterospecifics

2014 ◽  
Author(s):  
Christopher Hassall
Keyword(s):  
Character Displacement ◽  
Step Change ◽  
Strong Variation ◽  
Closely Related Species ◽  
Wing Pigmentation ◽  
Primary Driver ◽  
Potential Benefits ◽  
Southern Border ◽  
Calopteryx Maculata ◽  
Discrete Populations

Wing pigmentation in Calopteryx damselflies, caused by the deposition of melanin, is energetically expensive to produce and enhances predation risk. However, patterns of melanisation are used in species identification, greater pigmentation is an accurate signal of male immune function in at least some species, and there may be a role for pigment in thermoregulation. This study tested two potential hypotheses to explain the presence of, and variation in, this pigmentation based on these three potential benefits using 907 male specimens of Calopteryx maculata collected from 49 sites (34 discrete populations) across the geographical range of the species in North America: (i) pigmentation varies with the presence of the closely related species, Calopteryx aequabilis, and (ii) pigment increases at higher latitudes as would be expected if it enhances thermoregulatory capacity. No gradual latitudinal pattern was observed, as might be expected if pigmentation was involved in thermoregulation. However, strong variation was observed between populations that were sympatric or allopatric with C. aequabilis. This variation was characterised by dark wings through allopatry in the south of the range and then a step change to much lighter wings at the southern border of sympatry. Pigmentation then increased further north into the sympatric zone, finally returning to allopatry levels at the northern range margin. These patterns are qualitatively similar to variation in pigmentation in C. aequabilis, meaning that the data are consistent with what would be expected from convergent character displacement. Overall, the results corroborate recent research that has suggested sexual selection as a primary driver behind the evolution of wing pigmentation in this group.

scholarly journals Selection on male sex pheromone composition contributes to butterfly reproductive isolation

2015 ◽  
Vol 282 (1804) ◽  
pp. 20142734 ◽  
Author(s):  
P. M. B. Bacquet ◽  
O. Brattström ◽  
H.-L. Wang ◽  
C. E. Allen ◽  
C. Löfstedt ◽  
...  
Keyword(s):  
Sex Pheromone ◽  
Mate Choice ◽  
Reproductive Isolation ◽  
Species Recognition ◽  
Sensory Modality ◽  
Character Displacement ◽  
Reproductive Character Displacement ◽  
Male Sex Pheromone ◽  
Pheromone Composition ◽  
Male Sex

Selection can facilitate diversification by inducing character displacement in mate choice traits that reduce the probability of maladaptive mating between lineages. Although reproductive character displacement (RCD) has been demonstrated in two-taxa case studies, the frequency of this process in nature is still debated. Moreover, studies have focused primarily on visual and acoustic traits, despite the fact that chemical communication is probably the most common means of species recognition. Here, we showed in a large, mostly sympatric, butterfly genus, a strong pattern of recurrent RCD for predicted male sex pheromone composition, but not for visual mate choice traits. Our results suggest that RCD is not anecdotal, and that selection for divergence in male sex pheromone composition contributed to reproductive isolation within the Bicyclus genus. We propose that selection may target olfactory mate choice traits as a more common sensory modality to ensure reproductive isolation among diverging lineages than previously envisaged.

scholarly journals Continental variation in wing pigmentation in Calopteryx damselflies is related to the presence of heterospecifics

2014 ◽  
Author(s):  
Christopher Hassall
Keyword(s):  
Character Displacement ◽  
Step Change ◽  
Strong Variation ◽  
Closely Related Species ◽  
Wing Pigmentation ◽  
Primary Driver ◽  
Potential Benefits ◽  
Southern Border ◽  
Calopteryx Maculata ◽  
Discrete Populations

Wing pigmentation in Calopteryx damselflies, caused by the deposition of melanin, is energetically expensive to produce and enhances predation risk. However, patterns of melanisation are used in species identification, greater pigmentation is an accurate signal of male immune function in at least some species, and there may be a role for pigment in thermoregulation. This study tested two potential hypotheses to explain the presence of, and variation in, this pigmentation based on these three potential benefits using 907 male specimens of Calopteryx maculata collected from 49 sites (34 discrete populations) across the geographical range of the species in North America: (i) pigmentation varies with the presence of the closely related species, Calopteryx aequabilis, and (ii) pigment increases at higher latitudes as would be expected if it enhances thermoregulatory capacity. No gradual latitudinal pattern was observed, as might be expected if pigmentation was involved in thermoregulation. However, strong variation was observed between populations that were sympatric or allopatric with C. aequabilis. This variation was characterised by dark wings through allopatry in the south of the range and then a step change to much lighter wings at the southern border of sympatry. Pigmentation then increased further north into the sympatric zone, finally returning to allopatry levels at the northern range margin. These patterns are qualitatively similar to variation in pigmentation in C. aequabilis, meaning that the data are consistent with what would be expected from convergent character displacement. Overall, the results corroborate recent research that has suggested sexual selection as a primary driver behind the evolution of wing pigmentation in this group.

scholarly journals Reinforcement generates reproductive isolation between neighbouring conspecific populations of spadefoot toads

2014 ◽  
Vol 281 (1789) ◽  
pp. 20140949 ◽  
Author(s):  
Karin S. Pfennig ◽  
Amber M. Rice
Keyword(s):  
Gene Flow ◽  
Reproductive Isolation ◽  
Character Displacement ◽  
Mate Preferences ◽  
Reproductive Character Displacement ◽  
Pure Species ◽  
Interacting Species ◽  
Spadefoot Toads ◽  
Reproductive Character ◽  
Species Population

Reproductive character displacement is the adaptive evolution of traits that minimize deleterious reproductive interactions between species. When arising from selection to avoid hybridization, this process is referred to as reinforcement. Reproductive character displacement generates divergence not only between interacting species, but also between conspecific populations that are sympatric with heterospecifics versus those that are allopatric. Consequently, such conspecific populations can become reproductively isolated. We compared female mate preferences in, and evaluated gene flow between, neighbouring populations of spadefoot toads that did and did not occur with heterospecifics (mixed- and pure-species populations, respectively). We found that in mixed-species populations females significantly preferred conspecifics. Such females also tended to prefer a conspecific call character that was dissimilar from heterospecifics. By contrast, females from pure-species populations did not discriminate conspecific from heterospecific calls. They also preferred a more exaggerated conspecific call character that resembles heterospecific males. Moreover, gene flow was significantly reduced between mixed- and pure-species population types. Thus, character displacement (and, more specifically, reinforcement) may initiate reproductive isolation between conspecific populations that differ in interactions with heterospecifics.

scholarly journals Quantitative variation in female sensory structures supports species recognition and intraspecific mate choice functions in damselflies

2018 ◽  
Author(s):  
Alexandra A. Barnard ◽  
John P. Masly
Keyword(s):  
Mate Choice ◽  
Reproductive Isolation ◽  
Species Recognition ◽  
Character Displacement ◽  
Physical Contact ◽  
Reproductive Character Displacement ◽  
Species Identity ◽  
Sensory Structures ◽  
Males And Females ◽  
Species Specific

AbstractMales and females exchange signals prior to mating that convey information such as sex, species identity, or individual condition. Tactile signals relayed during physical contact between males and females before and during mating appear to be important for mate choice and reproductive isolation in some animals. However, compared to our understanding of visual, auditory, and chemical signals, we know little about the importance of tactile signals in mating decisions. Among North American damselflies in the genus Enallagma (Odonata: Coenagrionidae) species-specific tactile stimulation contributes to reproductive isolation between species and may also be important for intraspecific mate choice. We quantified several mechanosensory sensilla phenotypes on the female thorax among multiple sympatric and allopatric populations of two Enallagma species that occasionally interbreed in nature. Although each species differed in features of sensilla distribution within the thoracic plates, we found no strong evidence of reproductive character displacement among the sensilla traits we measured in regions of sympatry. However, substantial variation of sensilla traits was observed within populations of both species. Our results suggest that species-specific placement of female mechanoreceptors appears sufficient for species recognition, but mechanosensor variation among females within species may be important for mate choice.

Sign in / Sign up

Export Citation Format

Share Document