| female stickleback prefer shallow males: sexual selection on nest microhabitat. | sexual selection is most often thought of as acting on organismal traits, such as size or color. however, individuals' habitat use may also affect mating success. here, we show that, in threespine stickleback, nest depth can be a target of sexual selection. in postglacial lakes in british columbia, male threespine stickleback nest in a narrow range of depths. prior studies revealed heritable variation in males' preferred nest microhabitat. we surveyed four natural populations, finding that male ... | 2015 | 25958935 |
| among-lake reciprocal transplants induce convergent expression of immune genes in threespine stickleback. | geographic variation in parasite communities can drive evolutionary divergence in host immune genes. however, biotic and abiotic environmental variation can also induce plastic differences in immune function among populations. at present, there is little information concerning the relative magnitudes of heritable vs. induced immune divergence in natural populations. we examined immune gene expression profiles of threespine stickleback (gasterosteus aculeatus) from six lakes on vancouver island, ... | 2015 | 26118468 |
| admixture mapping of male nuptial colour and body shape in a recently formed hybrid population of threespine stickleback. | despite recent progress, we still know relatively little about the genetic architecture that underlies adaptation to divergent environments. determining whether the genetic architecture of phenotypic adaptation follows any predictable patterns requires data from a wide variety of species. however, in many organisms, genetic studies are hindered by the inability to perform genetic crosses in the laboratory or by long generation times. admixture mapping is an approach that circumvents these issues ... | 2012 | 22681397 |
| character shifts in the defensive armor of sympatric sticklebacks. | natural enemies may contribute to the morphological divergence of sympatric species, yet their role has received little attention to date. we tested for character shifts in defensive armor of sympatric threespine sticklebacks (gasterosteus aculeatus complex) previously shown to exhibit ecological character displacement in traits related to resource use. we scored five defensive armor traits in sympatric benthic and limnetic stickleback species from southwestern british columbia and compared them ... | 2004 | 15068354 |
| the occurrence of lepeophtheirus salmonis and caligus clemensi (copepoda: caligidae) on three-spine stickleback gasterosteus aculeatus in coastal british columbia. | infections with sea lice species belonging to lepeophtheirus and caligus are reported from examinations of 1,309 three-spine sticklebacks collected in coastal british columbia. over 97% of the 19,960 lepeophtheirus specimens and nearly 96% of the 2,340 caligus specimens were in the copepodid and chalimus developmental stages. the parasites were identified as lepeophtheirus salmonis and caligus clemensi based on morphology of adult stages. between 1,763 and 1,766 base pairs (bp) of 18s rdna from ... | 2006 | 16883988 |
| quantifying the constraining influence of gene flow on adaptive divergence in the lake-stream threespine stickleback system. | the constraining effect of gene flow on adaptive divergence is often inferred but rarely quantified. we illustrate ways of doing so using stream populations of threespine stickleback (gasterosteus aculeatus) that experience different levels of gene flow from a parapatric lake population. in the misty lake watershed (british columbia, canada), the inlet stream population is morphologically divergent from the lake population, and presumably experiences little gene flow from the lake. the outlet st ... | 2007 | 17683442 |
| sea lice, lepeophtheirus salmonis, transfer between wild sympatric adult and juvenile salmon on the north coast of british columbia, canada. | we examine sea lice, lepeophtheirus salmonis, on juvenile and adult salmon from the north coast of british columbia between 2004 and 2006 in an area that does not at present contain salmon farms. there is a pronounced zonation in the abundance of l. salmonis on juvenile pink salmon, oncorhynchus gorbuscha, in the skeena and nass estuaries. abundances in the proximal and distal zones of these estuaries are 0.01 and 0.05 respectively. the outer zones serve as feeding and staging areas for the pink ... | 2009 | 19245630 |
| evolutionary diversification in stickleback affects ecosystem functioning. | explaining the ecological causes of evolutionary diversification is a major focus of biology, but surprisingly little has been said about the effects of evolutionary diversification on ecosystems. the number of species in an ecosystem and their traits are key predictors of many ecosystem-level processes, such as rates of productivity, biomass sequestration and decomposition. here we demonstrate short-term ecosystem-level effects of adaptive radiation in the threespine stickleback (gasterosteus a ... | 2009 | 19339968 |
| the diversity of sea lice (copepoda: caligidae) parasitic on threespine stickleback (gasterosteus aculeatus) in coastal british columbia. | the prevalence, intensity, and abundance of sea lice belonging to lepeophtheirus or caligus clemensi are reported from threespine stickleback (gasterosteus aculeatus) collected from the broughton archipelago region of coastal british columbia, canada, between 2005 and 2008. in total, 25,130 sea lice were collected from 7,684 sticklebacks. the prevalence of lepeophtheirus ranged from 51% in 2005 to 11% in 2008 and that of c. clemensi from 56% in 2007 to 24% in 2008. chalimus stages accounted for ... | 2011 | 21506860 |
| sexual dimorphism and speciation on two ecological coins: patterns from nature and theoretical predictions. | adaptive divergence of phenotypes, such as sexual dimorphism or adaptive speciation, can result from disruptive selection via competition for limited resources. theory indicates that speciation and sexual dimorphism can result from identical ecological conditions, but co-occurrence is unlikely because whichever evolves first should dissipate the disruptive selection necessary to drive evolution of the other. here, we consider ecological conditions in which disruptive selection can act along mult ... | 2011 | 21884056 |
| asymmetry in structural defenses: insights into selective predation in the wild. | assessment of geographical patterns in fluctuating asymmetry (small, random differences between sides of bilateral characters) among populations shows promise as a tool to resolve the relative biomechanical importance of traits, in addition to being a possible indicator of habitat quality. we used 115 endemic freshwater populations of threespine stickleback (gasterosteus aculeatus) from haida gwaii (queen charlotte islands), british columbia, canada, to explore the degree of concordance between ... | 2003 | 14575332 |
| adaptive divergence and the balance between selection and gene flow: lake and stream stickleback in the misty system. | we investigated the interplay between natural selection and gene flow in the adaptive divergence of threespine stickleback (gasterosteus aculeatus) that reside parapatrically in lakes and streams. within the misty lake system (vancouver island, british columbia), stickleback from the inlet stream (flowing into the lake) have fewer gill rakers and deeper bodies than stickleback from the lake--differences thought to facilitate foraging (benthic macroinvertebrates in the stream vs. zooplankton in t ... | 2002 | 12144020 |
| speciation in reverse: morphological and genetic evidence of the collapse of a three-spined stickleback (gasterosteus aculeatus) species pair. | historically, six small lakes in southwestern british columbia each contained a sympatric species pair of three-spined sticklebacks (gasterosteus aculeatus). these pairs consisted of a 'benthic' and 'limnetic' species that had arisen postglacially and, in four of the lakes, independently. sympatric sticklebacks are considered biological species because they are morphologically, ecologically and genetically distinct and because they are strongly reproductively isolated from one another. the restr ... | 2006 | 16448405 |