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  • 1.
    Eckerström-Liedholm, Simon
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Sowersby, Will
    Kotrschal, Alexander
    Näslund, Joacim
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rowiński, Piotr
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Gonzalez-Voyer, Alejandro
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Fast life-histories are associated with larger brain size in killifishesManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Comparative studies suggest a negative relationship between pace of life-history, and relative energetic investment into brain size. However, since brain size typically evolves as a correlated response to selection on body size, any lag in brain size evolution will result in a shift in relative brain size (e.g. small body – large relative brain size).Coevolution between body size and life-history hence has the potential to drive secondary associations between relative brain size and life-history, when body size is correlated with life history. However, as far as we know, the relationship between relative brain size and life-history strategy has not been examined in systems that simultaneously present marked contrasts in life-history but no concordant shifts in body size. Using a common garden approach, we test the association between relative brain size and life-history in 21 species of killifish; a study system that fulfils the aforementioned requirements. Contrary to the prediction that brain size evolves through energetic trade-offs with life-history, we found that adults, but not juveniles, of fast-living species had larger relative brain sizes. Rather than an energetic link to life-history, our results suggest that fast- and slow-living species differ in terms of how cognitively demanding environments they inhabit are, or alternatively in the ontogenetic timing of somatic vs. neural growth.

  • 2.
    Eckerström-Liedholm, Simon
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Sowersby, Will
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Morozov, Sergey
    van der Bijl, Wouter
    Rowiński, Piotr
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Gonzalez-Voyer, Alejandro
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Macroevolutionary evidence suggests trait-dependent coevolution between behaviour and life-historyManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Species with fast life-histories prioritize current over future reproduction, which ought to require greater energetic resources, but also results in a shorter time-period to realize their reproductive potential, compared to slow life-histories, which prioritize future reproduction. Hence, behaviours that increase access to both resources and mating opportunities, at a cost of increased mortality risk, are thought to coevolve with the pace of life-history. However, whether this prediction holds across species, is yet to be tested under standardized conditions. Here, we test how potentially risky behaviours, which facilitate access to resources and mating opportunities (i.e. activity, boldness and aggression), along with metabolic rate, correlates with the pace of life-history across 20 species of killifish, which present a remarkable divergence in the pace of their life-histories. We found a positive correlation between the pace of life-history and aggression, but not with any other behavioural traits or metabolic rate. Aggression is often expressed in the context of mating, while the other behaviours we measured might be more relevant for access to energetic resources. Our results therefore suggest that the trade-off between current and future reproduction plays a more prominent role in shaping mating behaviour, while behaviours related to acquisition of energetic resources may be more affected by ecological factors.

  • 3.
    Eckerström-Liedholm, Simon
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Sowersby, Will
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Morozov, Sergey
    van der Bijl, Wouter
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. University of British Columbia, Canada.
    Rowiński, Piotr K.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Gonzalez-Voyer, Alejandro
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Universidad Nacional Autónoma de México, Mexico.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Macroevolutionary evidence suggests trait-dependent coevolution between behavior and life-history2019Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 73, nr 11, s. 2312-2323Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Species with fast life-histories typically prioritize current over future reproductive events, compared to species with slow life-histories. These species therefore require greater energetic input into reproduction, and also likely have less time to realize their reproductive potential. Hence, behaviors that increase access to both resources and mating opportunities, at a cost of increased mortality risk, could coevolve with the pace of life-history. However, whether this prediction holds across species, remains untested under standardized conditions. Here, we test how risky behaviors, which facilitate access to resources and mating opportunities (i.e., activity, boldness, and aggression), along with metabolic rate, coevolve with the pace of life-history across 20 species of killifish that present remarkable divergences in the pace of life-history. We found a positive association between the pace of life-history and aggression, but interestingly not with other behavioral traits or metabolic rate. Aggression is linked to interference competition, and in killifishes is often employed to secure mates, while activity and boldness are more relevant for exploiting energetic resources. Our results suggest that the trade-off between current and future reproduction plays a more prominent role in shaping mating behavior, while behaviors related to energy acquisition may be influenced by ecological factors.

  • 4.
    Rowiński, Piotr K.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Evolutionary consequences of maternal effects and stress2019Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Maternal effects occur when maternal environment or phenotype influence offspring phenotype, in addition to genetic contribution of the mother. As maternal effects often influence phenotypes that are under natural selection, they hence have evolutionary consequences. Further, the expression of both maternal effects and evolutionary potential has been argued to depend on environmental conditions, but the evidence of this dependency for the process of adaptation has been inconclusive. The main objective of this thesis was to investigate evolutionary consequences of maternal effects and stressful or variable environmental conditions.

    I started by performing a meta-analysis of quantitative genetic studies that investigated expression of additive genetic, maternal, and residual variance under both stressful and benign environmental conditions (Paper I). Data spanning over many animal taxa and stress types revealed that high levels of environmental stress correlated with increased expression of genetic and residual variances. However, against our predictions, maternal effects were relatively unaffected by stress.

    In Paper II and III, I explored the evolutionary divergences of traits previously shown to be under maternal control. Specifically, in Paper II, I performed a second meta-analysis, that investigated if parents of common frogs (Rana temporaria) influenced offspring development time to mediate the effects of time constraints, across a latitudinal cline. I found that reproductive delay in the parental generation correlated with decreased development time in tadpoles of northern R. temporaria populations, suggesting that parental effects may further decrease development time in populations from time-constrained environments.

    In Paper III, I used an annual killifish system, to explore if environmental unpredictability, measured by variation in precipitation during rainy season, correlated with maternally mediated variation in embryo development time (bet-hedging). Although I found significant among-species differences in variation in development time, there was no clear linear relationship between variation in development time and precipitation. The results suggest that either bet-hedging is not important for persistence in the unpredictable annual killifish habitats, or that other ecological factors, rather than precipitation unpredictability, influenced evolution of variation in development times.

    Lastly, I investigated if occurrence of placenta correlated with increased offspring brain size among poeciliid fish (Paper IV). In contrast to our prediction, I did not find any consistent differences in relative brain size between the fry of placental and non-placental species. It is possible that either the poeciliid placental structures do not have a sufficient capacity to transfer resources necessary for increased brain development, or that other factors, such as sexual selection, or differences in food abundance and competition, shaped brain evolution among poeciliids.

    In conclusion, the results of this thesis suggest that environmental stress may influence evolutionary potential by increasing genetic variation available for selection, that time-constrained habitats may be conducive to evolution of parental effects on offspring development times, and that maternal influence on offspring traits may be difficult to detect, as many ecological factors may potentially influence evolution of life-history and morphology traits.

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  • 5.
    Rowiński, Piotr K.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Laurila, Anssi
    Gotthard, Karl
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Sowersby, Will
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Lind, Martin
    Richter-Boix, Alex
    Eckerström-Liedholm, Simon
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Parental effects influence life history traits and covary with an environmental cline in common frog populations2020Ingår i: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 192, nr 4, s. 1013-1022Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Across latitudinal clines, the juvenile developmental rates of ectotherms often covary with the length of the growing season, due to life-history trade-offs imposed by the time-constrained environments. However, as the start of the growing season often varies substantially across years, adaptive parental effects on juvenile developmental rates may mediate the costs of a delayed season. By employing a meta-analysis, we tested whether larval developmental rates across a latitudinal cline of the common frog (Rana temporaria) are affected by fluctuating onsets of breeding, across years. We predicted that larval developmental rate will be inversely related to the onset of breeding, and that northern populations will be more prone to shorten their developmental rate in response to late breeding, as the costs of delayed metamorphosis should be highest in areas with a shorter growing season. We found that the larval period of both northern and southern populations responded to parental environmental conditions to a similar degree in absolute terms, but in different directions. In northern populations, a late season start correlated with decreased development time, suggesting that the evolution of parental effects aids population persistence in time-constrained environments. In southern populations, late season start correlated with increased development time, which could potentially be explained as a predator avoidance strategy. Our findings suggest that local ecological variables can induce adaptive parental effects, but responses are complex, and likely trade-off with other ecological factors.

  • 6.
    Rowiński, Piotr K.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen. Uppsala University, Sweden.
    Mateos-Gonzalez, F.
    Sandblom, E.
    Jutfelt, F.
    Ekström, A.
    Sundström, L. F.
    Warming alters the body shape of European perch Perca fluviatilis2015Ingår i: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 87, nr 5, s. 1234-1247Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The consequences of elevated temperature on body shape were investigated by comparing European perch Perca fluviatilis from the Forsmark area of the Baltic Sea to P. fluviatilis from a nearby Biotest enclosure. The Biotest is a man-made enclosure within the Baltic Sea that has received warm water from a nuclear power plant since 1980, resulting in temperatures that are elevated 5-10 degrees C relative to the surrounding Baltic Sea. Sampled fish ranged from young-of-the-year to 14years. Geometric morphometrics and multivariate statistical analysis revealed significant morphological differences between individuals of P. fluviatilis from these two habitats. Most importantly, relative shape changed with size, with small individuals of P. fluviatilis from Biotest being characterized by a deeper body shape and a larger caudal peduncle than the smaller Baltic individuals. In large specimens, smaller differences were found with Biotest individuals being more slender than Baltic individuals. These results show that, in order to have a full understanding of the biological effects of elevated temperatures, studies that cover the entire size range of organisms will be important. Apart from the direct influence of temperature on growth rate and body shape, other ecological factors affected by temperature are discussed as possible contributors to the observed differences between the two populations.

  • 7.
    Rowiński, Piotr K.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Environmental stress correlates with increases in both genetic and residual variances: A meta-analysis of animal studies2017Ingår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, nr 5, s. 1339-1351Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Adaptive evolutionary responses are determined by the strength of selection and amount of genetic variation within traits, however, both are known to vary across environmental conditions. As selection is generally expected to be strongest under stressful conditions, understanding how the expression of genetic variation changes across stressful and benign environmental conditions is crucial for predicting the rate of adaptive change. Although theory generally predicts increased genetic variation under stress, previous syntheses of the field have found limited support for this notion. These studies have focused on heritability, which is dependent on other environmentally sensitive, but nongenetic, sources of variation. Here, we aim to complement these studies with a meta-analysis in which we examine changes in coefficient of variation (CV) in maternal, genetic, and residual variances across stressful and benign conditions. Confirming previous analyses, we did not find any clear direction in how heritability changes across stressful and benign conditions. However, when analyzing CV, we found higher genetic and residual variance under highly stressful conditions in life-history traits but not in morphological traits. Our findings are of broad significance to contemporary evolution suggesting that rapid evolutionary adaptive response may be mediated by increased evolutionary potential in stressed populations.

  • 8.
    Rowiński, Piotr
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Laurila, Anssi
    Gotthard, Karl
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Sowersby, Will
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Lind, Martin
    Richter-Boix, Alex
    Eckerström-Liedholm, Simon
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Thermally induced parental effects influence life history traits and covary with an environmental cline in common frog populationsManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Across latitudinal clines, the juvenile developmental rates of ectotherms often covary with the length of the growing season, due to life-history trade-offs imposed by time-constrained environments. However, as the start of the growing season often varies substantially across years, adaptive parental effects on juvenile developmental rates may mediate the costs of a delayed spring. By employing a meta-analysis, we tested whether larval developmental rates across a latitudinal cline of common frogs (Rana temporaria) are affected by fluctuating onsets of breeding, across years. We predicted that larval developmental rate will be inversely related to the onset of breeding, and that northern populations will be more prone to shorten their developmental rate in response to late breeding, as the costs of delayed metamorphosis should be highest in areas with a shorter growing season. We found that the larval period of both northern and southern populations responded to parental environmental conditions to similar degree in absolute terms, but in different directions. In northern populations, a late season start correlated with decreased development time, suggesting that the evolution of parental effects aid population persistence in time-constrained environments. In southern populations, late season start correlated with increased development time, which could potentially be explained as a predator avoidance strategy. Our findings suggest that local ecological variables can induce adaptive parental effects, but responses are complex, and likely trade-off with other ecological factors.

  • 9.
    Rowiński, Piotr
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Näslund, Joacim
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Sowersby, Will
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Eckerström-Liedholm, Simon
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    The evolution of a placenta is not linked to increased brain size in poeciliid fishesManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Maternal investment traits are considered to have a direct influence on the size of energetically costly organs, including the brain. In placental organisms, offspring are supplied with nutrients during pre-natal development, which in turn may modulate brain size evolution. While this hypothesis has received some support in mammals (i.e. in the marsupial/placental transition), how the evolution of the placenta affects brain size in other taxa is largely unknown.Here, we use eight poeciliid fish species to test if species with placental transferred nutrients, invest more resources into offspring brain development than species with no placental structures. We predicted that the evolution of the placenta would be associated with larger relative brain size in fry, and possibly also shallower ontogenetic brain size allometry, if cognitive demands are similar in adults across placental and non-placental species. We tested these hypotheses by taking non-invasive brain size measurements during the first four weeks of life, and relating these to corresponding somatic growth. Contrary to our expectations, we did not find any differences in brain size between the two maternal strategies. Furthermore, we did not find any differences in how relative brain size changed over ontogenetic development between placental and non-placental species. Elsewhere, maternal investment traits have been commonly linked to brain size, however the species investigated here only exhibit pre-natal provisioning, which may reduce the potential for maternal investment into brain size. Our results suggest that coevolution between placental structures and juvenile brain size is not a general pattern.

  • 10.
    Rowiński, Piotr
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Sowersby, Will
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Näslund, Joacim
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Eckerström-Liedholm, Simon
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Gotthard, Karl
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Variation in developmental rates is not linked to environmental unpredictability in annual killifishesManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Comparative evidence suggests that adaptive plasticity may evolve as a response to predictable environmental variation. However, receiving less attention is unpredictable environmental variation, which is considered to affect evolutionary trajectories by increasing phenotypic variation (bet-hedging). If increased variance in development time evolved as an adaptation to unpredictable environmental conditions, we would expect species inhabiting locations with unpredictable conditions to have a higher variance in development time. Here, we examine the occurrence of bet-hedging in egg developmental rate in seven species of annual killifish, originating from a gradient of precipitation rate variation, under three different incubation temperatures (21°C, 23°C, and 25°C). These fish species persist as dormant eggs buried in the soil, in seasonal environments with regular habitat desiccation. At the onset of the rainy season, the eggs must be sufficiently developed in order to hatch, and complete their life-cycle. We found substantial differences among species in both mean and variation of egg development rates, as well as species-specific plastic temperature responses. However, there was no clear relationship between variation in egg development time and variation in precipitation (environmental predictability). Hence, if species specific variances are adaptive, they do not diverge in accordance with simple linear relationship to variation in precipitation.

  • 11. Sowersby, Will
    et al.
    Eckerström-Liedholm, Simon
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rowiński, Piotr
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Balogh, Julia
    Eiler, Stefan
    Upstone, Joseph
    Gonzalez-Voyer, Alejandro
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Rogell, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Zoologiska institutionen.
    Costly sexual ornaments coevolve with fast life-histories in killifishesManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Sexually selected ornaments constitute an important investment into reproduction, increasing current mating success, at a potential cost to survival. Theory suggests that exaggerated sexual ornaments may coevolve with the life-history trade-off between current and future reproduction, however this hypothesis has remained unexplored. Here, we determine how the size of secondary sexual traits coevolves with the pace of life-histories (slow or fast), using a clade of killifishes, where independent adaptations to ephemeral environments have resulted in substantial divergences in life-history strategy. In addition, we assess costs to swimming performance driven by enlarged, ornamental fins. We predict that killifishes with fast life-histories, which inhabit time-limited environments and prioritize current reproduction, will have a greater tendency to evolve enlarged fins, compared to killifishes with slow life-histories. Indeed, we found that species with fast life-histories had more pronounced sexual size dimorphism, with males from these species having exaggerated dorsal and anal fins, compared to species with slow life-histories. Furthermore, males from species with fast life-histories and larger ornaments exhibited lower swimming performances compared to both conspecific females, and individuals from species with slow life-histories. Our results indicate that the trade-off between current and future reproduction, can be an evolutionary driver of costly sexual ornaments.

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