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Stickleback Population (stickleback + population)

Distribution by Scientific Domains

Life Sciences	100%

Selected Abstracts

Behavioural syndromes differ predictably between 12 populations of three-spined stickleback

JOURNAL OF ANIMAL ECOLOGY, Issue 6 2007
NIELS J. DINGEMANSE
Summary 1Animals often differ in suites of correlated behaviours, comparable with how humans differ in personality. Constraints on the architecture of behaviour have been invoked to explain why such ,behavioural syndromes' exist. From an adaptationist viewpoint, however, behavioural syndromes should evolve only in those populations where natural selection has favoured such trait covariance, and they should therefore exist only in particular types of population. 2A comparative approach was used to examine this prediction of the adaptive hypothesis. We measured behavioural correlations in 12 different populations of three-spined stickleback (Gasterosteus aculeatus) and assessed whether they indeed varied consistently according to the selective environment, where population was unit of analysis. 3For a sample of fry from each population, we measured five different behaviours within the categories of (i) aggression (towards conspecifics); (ii) general activity; and (iii) exploration,avoidance (of novel foods, novel environments and altered environments). 4We show that behavioural syndromes are not always the same in different types of stickleback population: the often-documented syndrome between aggressiveness, activity and exploratory behaviour existed only in large ponds where piscivorous predators were present. In small ponds where predators were absent, these behaviours were not (or only weakly) associated. 5Our findings imply that population variation in behavioural syndromes does not result from stochastic evolutionary processes, but may result instead from adaptive evolution of behaviour favouring what should prove to be optimal trait combinations. [source]

Evolutionary significance of fecundity reduction in threespine stickleback infected by the diphyllobothriidean cestode Schistocephalus solidus

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2010
DAVID C. HEINS
Parasites may cause fecundity reduction in their hosts via life-history strategies involving simple nutrient theft or manipulation of host energy allocation. Simple theft of nutrients incidentally reduces host energy allocation to reproduction, whereas manipulation is a parasite-driven diversion of energy away from host reproduction. We aimed to determine whether the diphyllobothriidean cestode parasite Schistocephalus solidus causes loss of fecundity in the threespine stickleback fish (Gasterosteus aculeatus) through simple nutrient theft or the manipulation of host energy allocation. In one stickleback population (Walby Lake, Matanuska-Susitna Valley, Alaska), there was no difference in the sizes and ages of infected and uninfected reproducing females. Lightly- and heavily-infected females produced clutches of eggs, but increasingly smaller percentages of infected females produced clutches as the parasite-to-host biomass ratio (PI) increased. Infected, clutch-bearing sticklebacks showed reductions in clutch size, egg mass, and clutch mass, which were related to increases in PI and reflected a reduction in reproductive parameters as growth in parasite mass occurs. The findings obtained for this population are consistent with the hypothesis of simple nutrient theft; however, populations of S. solidus in other regions may manipulate host energy allocation. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 100, 835,846. [source]

Effects of genetics and light environment on colour expression in threespine sticklebacks

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 4 2008
EVA LEWANDOWSKI
The genetic basis of traits that are under sexual selection and that are involved in recognizing conspecific mates is poorly known, even in systems in which the phenotypic basis of these traits has been well studied. In the present study, we investigate genetic and environmental influences on nuptial colour, which plays important roles in sexual selection and sexual isolation in species pairs of limnetic and benthic threespine sticklebacks (Gasterosteus aculeatus species complex). Previous work demonstrated that colour differences among species correlate to differences in the ambient light prevalent in their mating habitat. Red fish are found in clear water and black fish in red-shifted habitats. We used a paternal half-sib split-clutch design to investigate the genetic and environmental basis of nuptial colour. We found genetic differences between a red and a black stickleback population in the expression of both red and black nuptial colour. In addition, the light environment influenced colour expression, and genotype by environment interactions were also present. We found evidence for both phenotypic and genetic correlations between our colour traits; some of these correlations are in opposite directions for our red and black populations. These results suggest that both genetic change and phenotypic plasticity underlie the correlation of male colour with light environment. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 663,673. [source]

Phylogeography of ninespine sticklebacks (Pungitius pungitius) in North America: glacial refugia and the origins of adaptive traits

MOLECULAR ECOLOGY, Issue 18 2010
JACLYN T. ALDENHOVEN
Abstract The current geographical distribution of the ninespine stickleback (Pungitius pungitius) was shaped in large part by the glaciation events of the Pleistocene epoch (2.6 Mya,10 Kya). Previous efforts to elucidate the phylogeographical history of the ninespine stickleback in North America have focused on a limited set of morphological traits, some of which are likely subject to widespread convergent evolution, thereby potentially obscuring relationships among populations. In this study, we used genetic information from both mitochondrial DNA (mtDNA) sequences and nuclear microsatellite markers to determine the phylogenetic relationships among ninespine stickleback populations. We found that ninespine sticklebacks in North America probably dispersed from at least three glacial refugia,the Mississippi, Bering, and Atlantic refugia,not two as previously thought. However, by applying a molecular clock to our mtDNA data, we found that these three groups diverged long before the most recent glacial period. Our new phylogeny serves as a critical framework for examining the evolution of derived traits in this species, including adaptive phenotypes that evolved multiple times in different lineages. In particular, we inferred that loss of the pelvic (hind fin) skeleton probably evolved independently in populations descended from each of the three putative North American refugia. [source]