scholarly journals Body size differences do not arise from divergent mate preferences in a species pair of threespine stickleback

2009 ◽  
Vol 5 (4) ◽  
pp. 517-520 ◽  
Author(s):  
Megan L Head ◽  
Emily A. Price ◽  
Janette W. Boughman

Ecological speciation can be driven by divergent natural and/or sexual selection. The relative contribution of these processes to species divergence, however, is unknown. Here, we investigate how sexual selection in the form of male and female mate preferences contributes to divergence of body size. This trait is known be under divergent natural selection and also contributes to sexual isolation in species pairs of threespine sticklebacks ( Gasterosteus aculeatus ). We show that neither female nor male size preferences contribute to body size divergence in this species pair, suggesting that size-based sexual isolation arises primarily through natural selection.

2009 ◽  
Vol 18 (14) ◽  
pp. 3110-3119 ◽  
Author(s):  
T. TAKAHASHI ◽  
K. WATANABE ◽  
H. MUNEHARA ◽  
L. RÜBER ◽  
M. HORI

2019 ◽  
Vol 116 (27) ◽  
pp. 13440-13445 ◽  
Author(s):  
Scott M. Villa ◽  
Juan C. Altuna ◽  
James S. Ruff ◽  
Andrew B. Beach ◽  
Lane I. Mulvey ◽  
...  

Ecological speciation occurs when local adaptation generates reproductive isolation as a by-product of natural selection. Although ecological speciation is a fundamental source of diversification, the mechanistic link between natural selection and reproductive isolation remains poorly understood, especially in natural populations. Here, we show that experimental evolution of parasite body size over 4 y (approximately 60 generations) leads to reproductive isolation in natural populations of feather lice on birds. When lice are transferred to pigeons of different sizes, they rapidly evolve differences in body size that are correlated with host size. These differences in size trigger mechanical mating isolation between lice that are locally adapted to the different sized hosts. Size differences among lice also influence the outcome of competition between males for access to females. Thus, body size directly mediates reproductive isolation through its influence on both intersexual compatibility and intrasexual competition. Our results confirm that divergent natural selection acting on a single phenotypic trait can cause reproductive isolation to emerge from a single natural population in real time.


1981 ◽  
Vol 37 (3) ◽  
pp. 275-284 ◽  
Author(s):  
Joseph H. Nadeau ◽  
Klaus Dietz ◽  
Robert H. Tamarin

SUMMARYThe selection component analysis developed by Christiansen & Frydenberg (1973, 1976) is a method to study the components of natural selection and is based on an analysis of population samples which include mothers and their progeny (mother–offspring combinations). Because only one progeny per mother–offspring combination is analysed, gametic selection and the reproductive components of selection in males are poorly characterized. We investigated the information which can be gained by analysing all progeny in each combination and showed that analysis of entire litters enables detection of gametic selection. Testing and estimation procedures are derived for this purpose. Sexual selection in males and mate preferences remain poorly characterized because the only information about the reproductive components in males is contained in the sample of male gametes and is insufficient to reconstruct the breeding structure of the male population. The format and interpretation of a selection component analysis is presented which takes these results into account.


1988 ◽  
Vol 66 (2) ◽  
pp. 467-474 ◽  
Author(s):  
Jeffrey V. Baumgartner ◽  
Michael A. Bell ◽  
Philip H. Weinberg

Two ecologically and morphologically divergent species of the Gasterosteus aculeatus (threespine stickleback) species complex occur in Enos Lake, Vancouver Island, British Columbia. The limnetic species swims in open water most of the time and feeds on plankton, and the benthic species lives near the shore in a structurally complex environment where it eats larger benthic prey. Based on design criteria inferred from hydrodynamic considerations, from other fishes, or from other populations of Gasterosteus, and on ecological differences between the two species, we expected that limnetic sticklebacks would have a more fusiform body, longer pectoral fins and snout, and larger eyes. Although some of these expected differences had been observed in a previous study of this species pair, others were verified for the first time in this study. Shape divergence between our samples results both from allometric trends coupled with differences in overall mean size and from size-free shape differences. Standard length is a poor proxy for general size (i.e., the first principal component of the morphometric variables) because several major features which differ between the species are dorsoventrally oriented. The marked morphometric divergence between these species has probably evolved within about the past 13 000 years, since deglaciation of Vancouver Island.


2013 ◽  
Vol 59 (5) ◽  
pp. 591-603 ◽  
Author(s):  
Alycia C. R. Lackey ◽  
Janette Wenrick Boughman

Abstract One approach to understand the importance of reproductive barriers to the speciation process is to study the breakdown of barriers between formerly distinct species. One reproductive barrier, sexual isolation, reduces gene flow between species through differences in mate preferences and mating signals and is likely important for species formation and maintenance. We measure sexual isolation in two limnetic-benthic threespine stickleback species pairs (Gasterosteus spp.). One species pair maintains strong reproductive isolation while the other species pair has recently collapsed into a hybrid swarm. We compare the strength of sexual isolation in the hybridizing pair to the currently isolated pair. We provide the first evidence that sexual isolation has been lost in the hybridizing pair and show furthermore that preferences females have for conspecific mates and the traits they use to distinguish conspecific and heterospecific males contribute to this loss. This work highlights the fragility of reproductive isolation between young species pairs and considers the role of sexual isolation in speciation.


2007 ◽  
Vol 64 (11) ◽  
pp. 1573-1580 ◽  
Author(s):  
Ricarda Modarressie ◽  
Theo C.M Bakker

Any trait of predatory species that enhances hunting efficiency should be favoured by natural selection. Foraging in threespine sticklebacks (Gasterosteus aculeatus) is mainly visually mediated. The visual system of sticklebacks is extended into the ultraviolet (UV) range of the spectrum. We tested, in four different experimental setups, the influence of different spectral compositions, in particular the presence and absence of ultraviolet wavelengths, on the feeding performance of threespine sticklebacks while foraging on live Daphnia magna, which absorb UV. In the three experiments with similar background reflections, the foraging behaviour of sticklebacks was unaffected by removing UV wavelengths. But in the fourth experiment, sticklebacks showed a significant difference between the rate of detecting prey against a UV-reflecting or UV-absorbing background. Sticklebacks significantly attacked prey faster when the background lacked UV reflections. Thus, the interaction of prey with its background in UV wavelengths influenced sticklebacks' prey detection. Removing long wavelengths impaired foraging rate, suggesting that long wavelengths may be more important in foraging tasks than UV wavelengths.


2020 ◽  
Author(s):  
Samuel Perini ◽  
Marina Rafajlović ◽  
Anja M. Westram ◽  
Kerstin Johannesson ◽  
Roger K. Butlin

AbstractWhen divergent populations are connected by gene flow, the establishment of complete reproductive isolation usually requires the joint action of multiple barrier effects. One example where multiple barrier effects are coupled consists of a single trait that is under divergent natural selection and also mediates assortative mating. Such multiple-effect traits can strongly reduce gene flow. However, there are few cases where patterns of assortative mating have been described quantitatively and their impact on gene flow has been determined. Two ecotypes of the coastal marine snail, Littorina saxatilis, occur in North Atlantic rocky-shore habitats dominated by either crab predation or wave action. There is evidence for divergent natural selection acting on size, and size-assortative mating has previously been documented. Here, we analyze the mating pattern in L. saxatilis with respect to size in intensively-sampled transects across boundaries between the habitats. We show that the mating pattern is mostly conserved between ecotypes and that it generates both assortment and directional sexual selection for small male size. Using simulations, we show that the mating pattern can contribute to reproductive isolation between ecotypes but the barrier to gene flow is likely strengthened more by sexual selection than by assortment.


Sign in / Sign up

Export Citation Format

Share Document