lnu.sePublications
Change search
Link to record
Permanent link

Direct link
BETA
Publications (10 of 110) Show all publications
Franzén, M., Forsman, A. & Betzholtz, P.-E. (2019). Variable color patterns influence continental range size and species-area relationships on islands. Ecosphere, 10(1), Article ID e02577.
Open this publication in new window or tab >>Variable color patterns influence continental range size and species-area relationships on islands
2019 (English)In: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 10, no 1, article id e02577Article in journal (Refereed) Published
Abstract [en]

It has been hypothesized that species with more variable color patterns should have higher establishment success and be less sensitive to environmental changes and local extinction compared with species that do not vary in color. This difference in colonization/extinction balance should manifest as larger continental range distributions and modulate the species-area relationship on true islands. We evaluated these predictions using data for 1216 species of butterflies and moths that differed with regard to inter-individual variation in color pattern. We show that species with more variable color patterns have larger continental range sizes in Europe compared with non-variable species. We also provide rare evidence that the slope of the species-area relationship on islands is steeper for species having non-variable color patterns, suggesting that to preserve 60% of non-variable species would require an area twice as large compared to what would be needed to preserve 60% of variable species. Our findings suggest that combining information on ecological characteristics with presence/absence data from small and medium sized islands can help identify traits that drive species range patterns at the continental scale, and that individual variation in color pattern can be used as a proxy for ecological generalization and the ability to cope with environmental change.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2019
Keywords
butterflies, colonization, color pattern variation, extinction, insects, island biogeography, life history, moths, polymorphism, range expansion, species-area relationship, trait
National Category
Ecology
Research subject
Natural Science, Ecology
Identifiers
urn:nbn:se:lnu:diva-80281 (URN)10.1002/ecs2.2577 (DOI)000456857400033 ()
Available from: 2019-02-07 Created: 2019-02-07 Last updated: 2019-02-07Bibliographically approved
Zverev, V., Kozlov, M., Forsman, A. & Zvereva, E. (2018). Ambient temperatures differently influence colour morphs of the leaf beetle Chrysomela lapponica: roles of thermal melanism and developmental plasticity. Journal of Thermal Biology, 74, 100-109
Open this publication in new window or tab >>Ambient temperatures differently influence colour morphs of the leaf beetle Chrysomela lapponica: roles of thermal melanism and developmental plasticity
2018 (English)In: Journal of Thermal Biology, ISSN 0306-4565, E-ISSN 1879-0992, Vol. 74, p. 100-109Article in journal (Refereed) Published
Abstract [en]

We asked whether ambient temperatures can affect morph frequencies within a subarctic population of thepolymorphic leaf beetle Chrysomela lapponica through thermal melanism and/or developmental plasticity. Bodytemperature increased faster in beetles of dark morph than in beetles of light morph under exposure to artificialirradiation. Dark males ran faster than light males in both field and laboratory experiments, and this differencedecreased with increasing ambient air temperature, from significant at 10 °C to non-significant at 20 °C and26 °C. On cold days (6–14 °C), significantly more dark males than light males were found on their host plants incopula (40.8% and 27.3% respectively); on warm days (15–22 °C) this difference disappeared. Light femalesproduced twice as many eggs as dark females; this difference did not depend on the ambient temperature. Theproportion of dark morphs in the progenies of pairs with one dark parent was twice as high as that in theprogenies of pairs in which both parents were light, and this proportion was greater when larvae developed atlow (10 and 15 °C) than at high (20 and 25 °C) temperatures. We conclude that low temperatures may increasethe frequencies of dark morphs in C. lapponica populations due to both the mating advantages of dark males overlight males and developmental plasticity. Variation in frequencies of low-fecund dark morphs in the population,caused by among-year differences in temperature together with density-dependent selection, may contribute tothe evolutionary dynamics of the colour polymorphism and may influence abundance fluctuations in these leafbeetle populations.

Place, publisher, year, edition, pages
Elsevier, 2018
National Category
Ecology
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-71800 (URN)10.1016/j.jtherbio.2018.03.019 (DOI)000436526200014 ()29801614 (PubMedID)
Available from: 2018-03-26 Created: 2018-03-26 Last updated: 2018-07-13Bibliographically approved
Yildirim, Y., Tinnert, J. & Forsman, A. (2018). Contrasting patterns of neutral and functional genetic diversity in stable and disturbed environments. Ecology and Evolution, 8(23), 12073-12089
Open this publication in new window or tab >>Contrasting patterns of neutral and functional genetic diversity in stable and disturbed environments
2018 (English)In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 8, no 23, p. 12073-12089Article in journal (Refereed) Published
Abstract [en]

Genetic structure among and diversity within natural populations is influenced by acombination of ecological and evolutionary processes. These processes can differentlyinfluence neutral and functional genetic diversity and also vary according toenvironmental settings. To investigate the roles of interacting processes as drivers ofpopulation‐level genetic diversity in the wild, we compared neutral and functionalstructure and diversity between 20 Tetrix undulata pygmy grasshopper populations indisturbed and stable habitats. Genetic differentiation was evident among the differentpopulations, but there was no genetic separation between stable and disturbedenvironments. The incidence of long‐winged phenotypes was higher in disturbedhabitats, indicating that these populations were recently established by flight‐capablecolonizers. Color morph diversity and dispersion of outlier genetic diversity, estimatedusing AFLP markers, were higher in disturbed than in stable environments,likely reflecting that color polymorphism and variation in other functionally importanttraits increase establishment success. Neutral genetic diversity estimated usingAFLP markers was lower in disturbed habitats, indicating stronger eroding effects onneutral diversity of genetic drift associated with founding events in disturbed comparedto stable habitats. Functional diversity and neutral diversity were negativelycorrelated across populations, highlighting the utility of outlier loci in genetics studiesand reinforcing that estimates of genetic diversity based on neutral markers donot infer evolutionary potential and the ability of populations and species to copewith environmental change.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2018
Keywords
color polymorphism, dispersal, evolution, grasshoppers, population genetics
National Category
Evolutionary Biology Evolutionary Biology Genetics
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-78896 (URN)10.1002/ece3.4667 (DOI)000454107200060 ()30598801 (PubMedID)
Funder
Swedish Research Council Formas, 2017-2007-364Swedish Research Council, 621-2010-5327
Available from: 2018-11-20 Created: 2018-11-20 Last updated: 2019-01-22Bibliographically approved
Forsman, A. (2018). On the role of sex differences for evolution in heterogeneous and changing fitness landscapes: insights from pygmy grasshoppers. Philosophical Transactions of the Royal Society of London. Biological Sciences, 373(1757), Article ID 20170429.
Open this publication in new window or tab >>On the role of sex differences for evolution in heterogeneous and changing fitness landscapes: insights from pygmy grasshoppers
2018 (English)In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 373, no 1757, article id 20170429Article, review/survey (Refereed) Published
Abstract [en]

Much research has been devoted to study evolution of local adaptations by natural selection, and to explore the roles of neutral processes and developmental plasticity for patterns of diversity among individuals, populations and species. Some aspects, such as evolution of adaptive variation in phenotypic traits in stable environments, and the role of plasticity in predictable changing environments, are well understood. Other aspects, such as the role of sex differences for evolution in spatially heterogeneous and temporally changing environments and dynamic fitness landscapes, remain elusive. An increased understanding of evolution requires that sex differences in development, physiology, morphology, life-history and behaviours are more broadly considered. Studies of selection should take into consideration that the relationships linking phenotypes to fitness may vary not only according to environmental conditions but also differ between males and females. Such opposing selection, sex-by-environment interaction effects of selection and sex-specific developmental plasticity can have consequences for population differentiation, local adaptations and for the dynamics of polymorphisms. Integrating sex differences in analytical frameworks and population comparisons can therefore illuminate neglected evolutionary drivers and reconcile unexpected patterns. Here, I illustrate these issues using empirical examples from over 20 years of research on colour polymorphic Tetrix subulata and Tetrix undulata pygmy grasshoppers, and summarize findings from observational field studies, manipulation experiments, common garden breeding experiments and population genetics studies. This article is part of the theme issue 'Linking local adaptation with the evolution of sex differences'.

Keywords
colour polymorphism, environmental change, local adaptation, phenotypic integration, sexual dimorphism, Tetrigidae
National Category
Evolutionary Biology
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-77718 (URN)10.1098/rstb.2017.0429 (DOI)000443010000013 ()30150227 (PubMedID)
Available from: 2018-09-13 Created: 2018-09-13 Last updated: 2018-10-24Bibliographically approved
Karpestam, E., Merilaita, S. & Forsman, A. (2018). Size variability effects on visual detection are influenced by colour pattern and perceived size. Animal Behaviour, 143, 131-138
Open this publication in new window or tab >>Size variability effects on visual detection are influenced by colour pattern and perceived size
2018 (English)In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 143, p. 131-138Article in journal (Refereed) Published
Abstract [en]

Most animals including humans use vision to detect, identify, evaluate and respond to potential prey items in complex environments. Theories predict that predators' visual search performance is better when targets are similar than when targets are dissimilar and require divided attention, and this may contribute to colour pattern polymorphism in prey. Most prey also vary in size, but how size variation influences detectability and search performance of predators that utilize polymorphic prey has received little attention. To evaluate the effect of size variability on prey detection we asked human subjects to search for images of black, grey and striped pygmy grasshoppers presented on computer screens in size-variable (large, medium and small) or in size-invariable (all medium) sequences (populations) against photographs of natural grasshopper habitat. Results showed that size variability either increased or reduced detection of medium-sized targets depending on colour morph. To evaluate whether bias in perceived size varies depending on colour pattern, subjects were asked to discriminate between two grasshopper images of identical size that were presented in pairs against a monochromatic background. Subjects more often incorrectly classified one of the two identical-sized targets as being larger than the other in colour-dimorphic than in monomorphic presentations. The distinctly patterned (striped) morph elicited stronger size perception biases than the dorsally grey or black morphs, and striped grasshoppers were incorrectly classified more often as smaller than grey grasshoppers. The direction of the effect of size variability on detection changed across colour patterns as the bias in perceived size increased. Such joint effects of variation in size and colour pattern on detection and perception can impact the outcome of behavioural and evolutionary interactions between visually oriented predators and their camouflaged prey. This may have consequences for population dynamics, evolution of polymorphisms, community species composition and ecosystem functioning. (C) 2018 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Place, publisher, year, edition, pages
Elsevier, 2018
Keywords
body size, camouflage, cognition, colour pattern polymorphism, crypsis, detection and perception, predation, visual stimuli
National Category
Evolutionary Biology
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-77721 (URN)10.1016/j.anbehav.2018.07.013 (DOI)000443386600013 ()
Available from: 2018-09-13 Created: 2018-09-13 Last updated: 2018-10-24Bibliographically approved
Nordahl, O., Tibblin, P., Koch-Schmidt, P., Berggren, H., Larsson, P. & Forsman, A. (2018). Sun-basking fish benefit from body temperatures that are higher than ambient water. Proceedings of the Royal Society of London. Biological Sciences, 285(1879), Article ID 20180639.
Open this publication in new window or tab >>Sun-basking fish benefit from body temperatures that are higher than ambient water
Show others...
2018 (English)In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 285, no 1879, article id 20180639Article in journal (Refereed) Published
Abstract [en]

In terrestrial environments, cold-blooded animals can attain higher bodytemperatures by sun basking, and thereby potentially benefit from broaderniches, improved performance and higher fitness. The higher heat capacityand thermal conductivity of water compared with air have been universallyassumed to render heat gain from sun basking impossible for aquaticectotherms, such that their opportunities to behaviourally regulate body temperatureare largely limited to choosing warmer or colder habitats. Here wechallenge this paradigm. Using physical modelswe first showthat submergedobjects exposed to natural sunlight attain temperatures in excess of ambientwater. We next demonstrate that free-ranging carp (Cyprinus carpio) canincrease their body temperature during aquatic sun basking close to thesurface. The temperature excess gained by basking was larger in dark thanin pale individuals, increased with behavioural boldness, and was associatedwith faster growth. Overall, our results establish aquatic sun basking as a novelecologically significant mechanism for thermoregulation in fish. The discoveryof this previously overlooked process has practical implications for aquaculture,offers alternative explanations for behavioural and phenotypicadaptations, will spur future research in fish ecology, and calls for modificationsof models concerning climate change impacts on biodiversity inmarine and freshwater environments.

National Category
Ecology Evolutionary Biology
Research subject
Natural Science, Ecology
Identifiers
urn:nbn:se:lnu:diva-75330 (URN)10.1098/rspb.2018.0639 (DOI)000433506100024 ()
Available from: 2018-06-07 Created: 2018-06-07 Last updated: 2018-11-16Bibliographically approved
Sunde, J., Tamario, C., Tibblin, P., Larsson, P. & Forsman, A. (2018). Variation in salinity tolerance between and within anadromous subpopulations of pike (Esox lucius). Scientific Reports, 8, Article ID 22.
Open this publication in new window or tab >>Variation in salinity tolerance between and within anadromous subpopulations of pike (Esox lucius)
Show others...
2018 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 22Article in journal (Refereed) Published
Abstract [en]

Environmental heterogeneity is a key determinant of genetic and phenotypic diversity. Stable andhomogenous environments tends to result in evolution of specialism and local adaptations, whiletemporally unpredictable environments may maintain a diversity of specialists, promote generaliststrategies, or favour diversified bet hedging strategies. We compared salinity tolerance between twoanadromous subpopulations of pike (Esox Lucius) that utilize freshwater spawning sites with differentsalinity regimes. Eggs from each population were artificially fertilized and incubated in a salinitygradient (0, 3, 5, 7, and 9 psu) using a split-brood design. Effects on embryonic development, hatchingsuccess, survival of larvae, and fry body length were compared between populations and families.The population naturally spawning in the stable freshwater habitat showed signs of specialization forfreshwater spawning. The population exposed to fluctuating selective pressure in a spawning area withoccasional brackish water intrusions tolerated higher salinities and displayed considerable variation inreaction norms. Genetic differences and plasticity of salinity tolerance may enable populations to copewith changes in salinity regimes associated with future climate change. That geographically adjacentsubpopulations can constitute separate units with different genetic characteristics must be consideredin management and conservation efforts to avoid potentially negative effects of genetic admixture onpopulation fitness and persistence.

Place, publisher, year, edition, pages
Nature Publishing Group, 2018
National Category
Ecology
Research subject
Natural Science, Ecology
Identifiers
urn:nbn:se:lnu:diva-69620 (URN)10.1038/s41598-017-18413-8 (DOI)000419441300022 ()29311634 (PubMedID)
Available from: 2018-01-08 Created: 2018-01-08 Last updated: 2018-10-24Bibliographically approved
Forsman, A. & Berggren, H. (2017). Can spatial sorting associated with spawning migration explain evolution of body size and vertebral number in Anguilla eels?. Ecology and Evolution, 7(2), 751-761
Open this publication in new window or tab >>Can spatial sorting associated with spawning migration explain evolution of body size and vertebral number in Anguilla eels?
2017 (English)In: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 7, no 2, p. 751-761Article in journal (Refereed) Published
Abstract [en]

Spatial sorting is a process that can contribute to microevolutionary change by assemblingphenotypes through space, owing to nonrandom dispersal. Here we first buildupon and develop the “neutral” version of the spatial sorting hypothesis by arguingthat in systems that are not characterized by repeated range expansions, the evolutionaryeffects of variation in dispersal capacity and assortative mating might not beindependent of but interact with natural selection. In addition to generating assortativemating, variation in dispersal capacity together with spatial and temporal variationin quality of spawning area is likely to influence both reproductive success and survivalof spawning migrating individuals, and this will contribute to the evolution of dispersal-enhancingtraits. Next, we use a comparative approach to examine whether differencesin spawning migration distance among 18 species of freshwater Anguilla eelshave evolved in tandem with two dispersal-favoringtraits. In our analyses, we use informationon spawning migration distance, body length, and vertebral number thatwas obtained from the literature, and a published whole mitochondrial DNA-basedphylogeny. Results from comparative analysis of independent contrasts showed thatmacroevolutionary shifts in body length throughout the phylogeny have been associatedwith concomitant shifts in spawning migration. Shifts in migration distance werenot associated with shifts in number of vertebrae. These findings are consistent withthe hypothesis that spatial sorting has contributed to the evolution of more elongatedbodies in species with longer spawning migration distances, or resulted in evolution oflonger migration distances in species with larger body size. This novel demonstrationis important in that it expands the list of ecological settings and hierarchical levels ofbiological organization for which the spatial sorting hypothesis seems to have predictivepower.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2017
National Category
Ecology
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-60282 (URN)10.1002/ece3.2671 (DOI)000392075300026 ()
Available from: 2017-01-27 Created: 2017-01-27 Last updated: 2018-10-24Bibliographically approved
Betzholtz, P.-E., Franzén, M. & Forsman, A. (2017). Colour pattern variation can inform about extinction risk in moths. Animal Conservation, 20(1), 72-79
Open this publication in new window or tab >>Colour pattern variation can inform about extinction risk in moths
2017 (English)In: Animal Conservation, ISSN 1367-9430, E-ISSN 1469-1795, Vol. 20, no 1, p. 72-79Article in journal (Refereed) Published
Abstract [en]

Theory posits that species with inter-individual variation in colour patterns should beless vulnerable to extinction, compared with species that do not vary in colour. Toevaluate this prediction, we explored whether differences in colour pattern diversitywas associated with extinction risk, using red-list status for more than 350 species ofnoctuid moths in Sweden. We also evaluated six other species characteristics thathave been proposed to influence extinction risk namely: host plant niche breadth,habitat type, area of occupancy, body size, overwintering life-history stage and lengthof flight activity period. We found that species with variable colour patterns hadreduced extinction risk overall compared with species having non-variable colourpatterns, and that this difference was pronounced more strongly among species havingsmaller areas of occupancy. There were also significant associations with hostplant niche breadth and habitat type, extinction risk being lower on average in polyphagousspecies and in generalist species that occupied different habitat types. Thesefindings represent the first evidence for insects that variable colouration is associatedwith reduced extinction risks. Information on colour pattern variation is readily availablefor many taxa and may be used as a cost-effective proxy for endangerment inthe work of halting national and global biodiversity loss.

Place, publisher, year, edition, pages
Wiley-Blackwell, 2017
Keywords
colour variation; extinction risk; red list; lepidoptera; moth; threat status; trait; niche breath.
National Category
Ecology
Research subject
Natural Science, Ecology
Identifiers
urn:nbn:se:lnu:diva-57817 (URN)10.1111/acv.12287 (DOI)000396047900012 ()
Available from: 2016-11-04 Created: 2016-11-04 Last updated: 2018-10-24Bibliographically approved
Tinnert, J. & Forsman, A. (2017). The role of dispersal for genetic and phenotypic variation: insights from comparisons of sympatric pygmy grasshoppers. Biological Journal of the Linnean Society, 122(1), 84-97
Open this publication in new window or tab >>The role of dispersal for genetic and phenotypic variation: insights from comparisons of sympatric pygmy grasshoppers
2017 (English)In: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 122, no 1, p. 84-97Article in journal (Refereed) Published
Abstract [en]

Patterns of genetic and phenotypic variation within and among populations are influenced by a complex interplay of ecological and evolutionary processes. Theory posits that gene flow should increase diversity within and reduce differentiation between populations. Evaluating these predictions is potentially complicated by selection, population dynamics and plasticity that may also affect genetic and phenotypic variation. Here, we compare genetic and morphological variation between sympatric populations of two pygmy grasshopper species, Tetrix subulata and T. undulata, that differ in dispersal capacity. We found that genetic differentiation between populations is lower on average in the generally dispersive T. subulata compared with the mostly sedentary T. undulata, suggesting that genetic structure in the latter species has been less influenced by the homogenizing effects of migration. Our results also provided weak support for the hypothesis that neutral genetic diversity within populations should be higher in T. subulata than in T. undulata. We further found that body size varied among populations in both species, but the differences seen in T. subulata did not parallel those seen in T. undulata, indicating that the two species have unique plasticity responses or that they have responded differently to shared selective regimes. Our findings illustrate the utility of the pairwise comparative approach and further highlight that results and conclusions may not be transferrable even between closely related species.

Place, publisher, year, edition, pages
Oxford University Press, 2017
Keywords
body size, dispersal polymorphism, evolution, genetic structure, Orthoptera, Tetrigidae, wing polymorphism
National Category
Developmental Biology
Research subject
Ecology, Evolutionary Biology
Identifiers
urn:nbn:se:lnu:diva-68074 (URN)10.1093/biolinnean/blx055 (DOI)000409213700007 ()
Available from: 2017-09-22 Created: 2017-09-22 Last updated: 2018-10-24Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0001-9598-7618

Search in DiVA

Show all publications