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Anders Berglund - One of the best experts on this subject based on the ideXlab platform.
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Hypoxia delays mating in the broad-nosed pipefish
Marine Biology Research, 2015Co-Authors: Josefin Sundin, Gunilla Rosenqvist, Anders BerglundAbstract:AbstractCourtship is an important part of the reproductive process, ensuring reproductive compatibility and conveying individual quality. One factor in aquatic environments that has the potential to influence courtship behaviours and mating propensity is the level of dissolved oxygen. Furthermore, hypoxic areas are currently spreading due to anthropogenic disturbance, such as eutrophication. In marine environments, hypoxia often occurs in shallow coastal regions that are particularly important areas for reproduction. Here, we investigated how types of reproductive behaviour were affected by mild hypoxia using the well-studied broad-nosed pipefish, Syngnathus typhle. More precisely, we investigated the impact of acute hypoxia on the reproductive behaviour preceding mating, and on the probability of mating, as well as on the latency until these occurred. We found that the latency period to courting and copulation occurring was prolonged in the low-oxygen environment. However, the total time spent courting a...
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Male mate choice relies on major histocompatibility complex class I in a sex‐role‐reversed pipefish
Journal of Evolutionary Biology, 2014Co-Authors: Olivia Roth, Anders Berglund, Gunilla Rosenqvist, Josefin Sundin, K. M. WegnerAbstract:Mate choice for compatible genes is often based on genes of the major histocompatibility complex (MHC). Although MHC-based mate choice is commonly observed in female choice, male mate choice remains elusive. In particular, if males have intense paternal care and are thus the choosing sex, male choice for females with dissimilar MHC can be expected. Here, we investigated whether male mate choice relies on MHC class I genes in the sex-role reversed pipefish Syngnathus typhle. In a mate choice experiment, we determined the relative importance of visual and olfactory cues by manipulating visibility and olfaction. We found that pipefish males chose females that maximize sequence-based amino acid distance between MHC class I genotypes in the offspring when olfactory cues were present. Under visual cues, large females were chosen, but in the absence of visual cues, the choice pattern was reversed. The use of sex-role reversed species thus revealed that sexual selection can lead to the evolution of male mate choice for MHC class I genes.
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Sex ratio and density affect sexual selection in a sex-role reversed fish
Evolution, 2013Co-Authors: Tonje Aronsen, Kenyon B. Mobley, Anders Berglund, Irja Ida Ratikainen, Gunilla RosenqvistAbstract:Understanding how demographic processes influence mating systems is important to decode ecological influences on sexual selection in nature. We manipulated sex ratio and density in experimental populations of the sex-role reversed pipefish Syngnathus typhle. We quantified sexual selection using the Bateman gradient (βss'), the opportunity for selection (I), and sexual selection (Is), and the maximum standardized sexual selection differential (smax'). We also measured selection on body length using standardized selection differentials (s') and mating differentials (m'), and tested whether the observed I and Is differ from values obtained by simulating random mating. We found that I, Is, and s'max, but not βss', were higher for females under female than male bias and the opposite for males, but density did not affect these measures. However, higher density decreased sexual selection (m' but not s') on female length, but selection on body length was not affected by sex ratio. Finally, Is but not I was higher than expected from random mating, and only for females under female bias. This study demonstrates that both sex ratio and density affect sexual selection and that disentangling interrelated demographic processes is essential to a more complete understanding of mating behavior and the evolution of mating systems.
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Altered Oceanic pH Impairs Mating Propensity in a Pipefish
Ethology, 2012Co-Authors: Josefin Sundin, Gunilla Rosenqvist, Anders BerglundAbstract:Anthropogenic disturbance is currently altering the environment of terrestrial as well as aquatic organisms. Those changes affect a variety of animal behaviours, which in turn may cause changes in species interactions, population dynamics and evolutionary processes. In marine ecosystems, nutrient enrichment may elevate pH, while it is reduced by carbon dioxide-induced ocean acidification. These two processes are not expected to balance one another but rather to affect the environment at different times and scales. We here show experimentally that an increase in water pH has a negative effect on mating propensity in the broad-nosed pipefish Syngnathus typhle, whereas lowered pH did not elicit the same detrimental effect. This study provides, to our knowledge, the first evidence that mating propensity is impaired by an increase in pH, suggesting that anthropogenic nutrient enrichment in aquatic ecosystems may change the processes of sexual selection and population dynamics solely on the basis of altered water pH.
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The effect of maternal body size on embryo survivorship in the broods of pregnant male pipefish
Behavioral Ecology and Sociobiology, 2011Co-Authors: Kenyon B. Mobley, Charlotta Kvarnemo, Anders Berglund, Ingrid Ahnesjö, Charlyn Partridge, Adam G. JonesAbstract:The occurrence of male pregnancy in the family Syngnathidae (seahorses, pipefishes, and sea dragons) provides an exceptionally fertile system in which to investigate issues related to the evolution of parental care. Here, we take advantage of this unique reproductive system to study the influence of maternal body size on embryo survivorship in the brood pouches of pregnant males of the broad-nosed pipefish, Syngnathus typhle . Males were mated with either two large females, two small females, a large then a small female, or a small then a large female. Our results show that offspring survivorship depends on an interaction between female body size and the number of eggs transferred by the female. Eggs of larger females deposited in large numbers are more likely to result in viable offspring than eggs of smaller females laid in large numbers. However, when females deposited smaller numbers of eggs, the eggs from smaller females were more likely to produce viable offspring compared to those from larger females. We found no evidence that this result was based on mating order, the relative sizes of competing females, or egg characteristics such as dry weight of eggs. Additionally, male body size did not significantly influence the survivorship of offspring during brooding. Our results suggest that the factors underlying offspring survivorship in pipefish may be more complex than previously believed, with multiple factors interacting to determine the fitness of individual offspring within the broods of pregnant males.
Gunilla Rosenqvist - One of the best experts on this subject based on the ideXlab platform.
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Female pipefish can detect the immune status of their mates
Behavioral Ecology and Sociobiology, 2015Co-Authors: Susanne H. Landis, Gunilla Rosenqvist, Josefin Sundin, Maude Poirier, Guro Øistensen Jørgensen, Olivia RothAbstract:Given the ubiquity of the parasites and their important fitness consequences on mate and offspring condition, selection for the ability to distinguish healthy from parasitized potential mates is a key process to enhance Darwinian fitness. In this study, we experimentally evaluated how the immunological experience of two potential partners influences mate choice, using the sex-role-reversed pipefish Syngnathus typhle . We exposed S. typhle to immune challenges with heat-killed Vibrio bacteria and investigated whether the activation of the immune system determined mate preferences. Our results demonstrate that the immune status of the potential partners influenced female mate preference, such that females that were exposed to an immune challenge became choosy and favored unchallenged males. Males, however, did not show any preferences for female immune status. In this context, we discuss mate choice decisions and behavioral plasticity as a complex result of immune challenge, severity of infection, as well as trans-generational effects.
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Hypoxia delays mating in the broad-nosed pipefish
Marine Biology Research, 2015Co-Authors: Josefin Sundin, Gunilla Rosenqvist, Anders BerglundAbstract:AbstractCourtship is an important part of the reproductive process, ensuring reproductive compatibility and conveying individual quality. One factor in aquatic environments that has the potential to influence courtship behaviours and mating propensity is the level of dissolved oxygen. Furthermore, hypoxic areas are currently spreading due to anthropogenic disturbance, such as eutrophication. In marine environments, hypoxia often occurs in shallow coastal regions that are particularly important areas for reproduction. Here, we investigated how types of reproductive behaviour were affected by mild hypoxia using the well-studied broad-nosed pipefish, Syngnathus typhle. More precisely, we investigated the impact of acute hypoxia on the reproductive behaviour preceding mating, and on the probability of mating, as well as on the latency until these occurred. We found that the latency period to courting and copulation occurring was prolonged in the low-oxygen environment. However, the total time spent courting a...
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Male mate choice relies on major histocompatibility complex class I in a sex‐role‐reversed pipefish
Journal of Evolutionary Biology, 2014Co-Authors: Olivia Roth, Anders Berglund, Gunilla Rosenqvist, Josefin Sundin, K. M. WegnerAbstract:Mate choice for compatible genes is often based on genes of the major histocompatibility complex (MHC). Although MHC-based mate choice is commonly observed in female choice, male mate choice remains elusive. In particular, if males have intense paternal care and are thus the choosing sex, male choice for females with dissimilar MHC can be expected. Here, we investigated whether male mate choice relies on MHC class I genes in the sex-role reversed pipefish Syngnathus typhle. In a mate choice experiment, we determined the relative importance of visual and olfactory cues by manipulating visibility and olfaction. We found that pipefish males chose females that maximize sequence-based amino acid distance between MHC class I genotypes in the offspring when olfactory cues were present. Under visual cues, large females were chosen, but in the absence of visual cues, the choice pattern was reversed. The use of sex-role reversed species thus revealed that sexual selection can lead to the evolution of male mate choice for MHC class I genes.
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Sex ratio and density affect sexual selection in a sex-role reversed fish
Evolution, 2013Co-Authors: Tonje Aronsen, Kenyon B. Mobley, Anders Berglund, Irja Ida Ratikainen, Gunilla RosenqvistAbstract:Understanding how demographic processes influence mating systems is important to decode ecological influences on sexual selection in nature. We manipulated sex ratio and density in experimental populations of the sex-role reversed pipefish Syngnathus typhle. We quantified sexual selection using the Bateman gradient (βss'), the opportunity for selection (I), and sexual selection (Is), and the maximum standardized sexual selection differential (smax'). We also measured selection on body length using standardized selection differentials (s') and mating differentials (m'), and tested whether the observed I and Is differ from values obtained by simulating random mating. We found that I, Is, and s'max, but not βss', were higher for females under female than male bias and the opposite for males, but density did not affect these measures. However, higher density decreased sexual selection (m' but not s') on female length, but selection on body length was not affected by sex ratio. Finally, Is but not I was higher than expected from random mating, and only for females under female bias. This study demonstrates that both sex ratio and density affect sexual selection and that disentangling interrelated demographic processes is essential to a more complete understanding of mating behavior and the evolution of mating systems.
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Altered Oceanic pH Impairs Mating Propensity in a Pipefish
Ethology, 2012Co-Authors: Josefin Sundin, Gunilla Rosenqvist, Anders BerglundAbstract:Anthropogenic disturbance is currently altering the environment of terrestrial as well as aquatic organisms. Those changes affect a variety of animal behaviours, which in turn may cause changes in species interactions, population dynamics and evolutionary processes. In marine ecosystems, nutrient enrichment may elevate pH, while it is reduced by carbon dioxide-induced ocean acidification. These two processes are not expected to balance one another but rather to affect the environment at different times and scales. We here show experimentally that an increase in water pH has a negative effect on mating propensity in the broad-nosed pipefish Syngnathus typhle, whereas lowered pH did not elicit the same detrimental effect. This study provides, to our knowledge, the first evidence that mating propensity is impaired by an increase in pH, suggesting that anthropogenic nutrient enrichment in aquatic ecosystems may change the processes of sexual selection and population dynamics solely on the basis of altered water pH.
Ingrid Ahnesjö - One of the best experts on this subject based on the ideXlab platform.
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Nutritional state - a survival kit for brooding pipefish fathers
Biological Journal of the Linnean Society, 2017Co-Authors: Gry Sagebakken, Charlotta Kvarnemo, Ingrid AhnesjöAbstract:A parent's nutritional state may influence its ability to provide care to offspring and ability to handle infections. In the broad-nosed pipefish, Syngnathus typhle, males care for their offspring ...
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Effects of egg size and oxygen treatment on embryo mortality and average embryo size in the broad-nosed pipefish
2016Co-Authors: Ines Braga Goncalves, Ingrid Ahnesjö, Charlotta KvarnemoAbstract:BragaGoncalvesetalProcB_datafile1.csv contains the data used for the analysis of the effects of egg size and oxygen treatment on embryo mortality and average embryo size in the pipefish Syngnathus typhle
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Male condition and embryo measurements after 24 days of brooding in normoxia and hypoxia in the broad-nosed pipefish
2016Co-Authors: Ines Braga Goncalves, Ingrid Ahnesjö, Charlotta KvarnemoAbstract:BragaGoncalvesetalJExpB_datafile2.csv contains the data used for the analysis of the effects of male size and oxygen treatment on male condition, embryo survival and average embryo weight in the pipefish Syngnathus typhle after 24 days of brooding
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Brood size and embryo mortality.
2016Co-Authors: Gry Sagebakken, Ingrid Ahnesjö, Charlotta KvarnemoAbstract:Mean number (± SE) of eggs at the time of mating (open bars) and of embryos (shaded bars) after approx. 50% of the brooding period in broad-nosed pipefish males (Syngnathus typhle) with brood pouches filled partially (N = 36) or fully (N = 38). Percent embryo mortality is shown for each of the two treatments.
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The evolutionary puzzle of egg size, oxygenation and parental care in aquatic environments
Proceedings of the Royal Society B: Biological Sciences, 2015Co-Authors: Ines Braga Goncalves, Ingrid Ahnesjö, Charlotta KvarnemoAbstract:Offspring fitness generally improves with increasing egg size. Yet, eggs of most aquatic organisms are small. A common but largely untested assumption is that larger embryos require more oxygen than they can acquire through diffusion via the egg surface, constraining egg size evolution. However, we found no detrimental effects of large egg size on embryo growth and survival under hypoxic conditions. We tested this in the broad-nosed pipefish, Syngnathus typhle, whose males provide extensive care (nourishment, osmoregulation and oxygenation) to their young in a brood pouch on their bodies. We took advantage of this species' pronounced variation in egg size, correlating positively with female size, and tested the effect of hypoxia (40% dissolved oxygen) versus fully oxygenated (100%) water on embryo size and survival of large versus small eggs after 18 days of paternal brooding. Egg size did not affect embryo survival, regardless of O2 treatment. While hypoxia affected embryo size negatively, both large and small eggs showed similar reductions in growth. Males in hypoxia ventilated more and males with large eggs swam more, but neither treatment affected their position in the water column. Overall, our results call into question the most common explanation for constrained egg size evolution in aquatic environments.
Charlotta Kvarnemo - One of the best experts on this subject based on the ideXlab platform.
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Nutritional state - a survival kit for brooding pipefish fathers
Biological Journal of the Linnean Society, 2017Co-Authors: Gry Sagebakken, Charlotta Kvarnemo, Ingrid AhnesjöAbstract:A parent's nutritional state may influence its ability to provide care to offspring and ability to handle infections. In the broad-nosed pipefish, Syngnathus typhle, males care for their offspring ...
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Effects of egg size and oxygen treatment on embryo mortality and average embryo size in the broad-nosed pipefish
2016Co-Authors: Ines Braga Goncalves, Ingrid Ahnesjö, Charlotta KvarnemoAbstract:BragaGoncalvesetalProcB_datafile1.csv contains the data used for the analysis of the effects of egg size and oxygen treatment on embryo mortality and average embryo size in the pipefish Syngnathus typhle
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Male condition and embryo measurements after 24 days of brooding in normoxia and hypoxia in the broad-nosed pipefish
2016Co-Authors: Ines Braga Goncalves, Ingrid Ahnesjö, Charlotta KvarnemoAbstract:BragaGoncalvesetalJExpB_datafile2.csv contains the data used for the analysis of the effects of male size and oxygen treatment on male condition, embryo survival and average embryo weight in the pipefish Syngnathus typhle after 24 days of brooding
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Brood size and embryo mortality.
2016Co-Authors: Gry Sagebakken, Ingrid Ahnesjö, Charlotta KvarnemoAbstract:Mean number (± SE) of eggs at the time of mating (open bars) and of embryos (shaded bars) after approx. 50% of the brooding period in broad-nosed pipefish males (Syngnathus typhle) with brood pouches filled partially (N = 36) or fully (N = 38). Percent embryo mortality is shown for each of the two treatments.
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The evolutionary puzzle of egg size, oxygenation and parental care in aquatic environments
Proceedings of the Royal Society B: Biological Sciences, 2015Co-Authors: Ines Braga Goncalves, Ingrid Ahnesjö, Charlotta KvarnemoAbstract:Offspring fitness generally improves with increasing egg size. Yet, eggs of most aquatic organisms are small. A common but largely untested assumption is that larger embryos require more oxygen than they can acquire through diffusion via the egg surface, constraining egg size evolution. However, we found no detrimental effects of large egg size on embryo growth and survival under hypoxic conditions. We tested this in the broad-nosed pipefish, Syngnathus typhle, whose males provide extensive care (nourishment, osmoregulation and oxygenation) to their young in a brood pouch on their bodies. We took advantage of this species' pronounced variation in egg size, correlating positively with female size, and tested the effect of hypoxia (40% dissolved oxygen) versus fully oxygenated (100%) water on embryo size and survival of large versus small eggs after 18 days of paternal brooding. Egg size did not affect embryo survival, regardless of O2 treatment. While hypoxia affected embryo size negatively, both large and small eggs showed similar reductions in growth. Males in hypoxia ventilated more and males with large eggs swam more, but neither treatment affected their position in the water column. Overall, our results call into question the most common explanation for constrained egg size evolution in aquatic environments.
Olivia Roth - One of the best experts on this subject based on the ideXlab platform.
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Grandparental immune priming in the pipefish Syngnathus typhle.
BMC Evolutionary Biology, 2017Co-Authors: Anne Beemelmanns, Olivia RothAbstract:Phenotypic changes in response to environmental influences can persist from one generation into the next. In many systems parental parasite experience influences offspring immune responses, known as transgenerational immune priming (TGIP). TGIP in vertebrates is mainly maternal and short-term, supporting the adaptive immune system of the offspring during its maturation. However, if fathers and offspring have a close physical connection, evolution of additional paternal immune priming can be adaptive. Biparental TGIP may result in maximized immunological protection. Here, we investigate multigenerational biparental TGIP in the sex-role reversed pipefish Syngnathus typhle by exposing grandparents to an immune challenge with heat-killed bacteria and assessing gene expression (44 target genes) of the F2-generation. Grandparental immune challenge induced gene expression of immune genes in one-week-old grandoffspring. Similarly, genes mediating epigenetic regulation including DNA-methylation and histone modifications were involved in grandparental immune priming. While grand-maternal impact was strong on genes of the complement component system, grand-paternal exposure changed expression patterns of genes mediating innate immune defense. In a system with male pregnancy, grandparents influenced the immune system of their grandoffspring in a sex-specific manner, demonstrating multigenerational biparental TGIP. The involvement of epigenetic effects suggests that TGIP via the paternal line may not be limited to the pipefish system that displays male pregnancy. While the benefits and costs of grandparental TGIP depend on the temporal heterogeneity of environmental conditions, multigenerational TGIP may affect host-parasite coevolution by dampening the amplitude of Red Queen Dynamics.
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Consistent Pattern of Local Adaptation during an Experimental Heat Wave in a Pipefish-Trematode Host- Parasite System
2016Co-Authors: Trematode Host-parasite System, Olivia Roth, Susanne H. Landis, Thorsten B.h. Reusch, Susanne H. L, Martin KalbeAbstract:Extreme climate events such as heat waves are expected to increase in frequency under global change. As one indirect effect, they can alter magnitude and direction of species interactions, for example those between hosts and parasites. We simulated a summer heat wave to investigate how a changing environment affects the interaction between the broad-nosed pipefish (Syngnathus typhle) as a host and its digenean trematode parasite (Cryptocotyle lingua). In a fully reciprocal laboratory infection experiment, pipefish from three different coastal locations were exposed to sympatric and allopatric trematode cercariae. In order to examine whether an extreme climatic event disrupts patterns of locally adapted host-parasite combinations we measured the parasite’s transmission success as well as the host’s adaptive and innate immune defence under control and heat wave conditions. Independent of temperature, sympatric cercariae were always more successful than allopatric ones, indicating that parasites are locally adapted to their hosts. Hosts suffered from heat stress as suggested by fewer cells of the adaptive immune system (lymphocytes) compared to the same groups that were kept at 18uC. However, the proportion of the innate immune cells (monocytes) was higher in the 18uC water. Contrary to ou
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Bacteria-type-specific biparental immune priming in the pipefish Syngnathus typhle.
Ecology and Evolution, 2016Co-Authors: Anne Beemelmanns, Olivia RothAbstract:The transfer of acquired and specific immunity against previously encountered bacteria from mothers to offspring boosts the immune response of the next generation and supports the development of a successful pathogen defense. While most studies claim that the transfer of immunity is a maternal trait, in the sex-role-reversed pipefish Syngnathus typhle, fathers nurse the embryos over a placenta-like structure, which opens the door for additional paternal immune priming. We examined the potential and persistence of bacteria-type-specific parental immune priming in the pipefish S. typhle over maturation time using a fully reciprocal design with two different bacteria species (Vibrio spp. and Tenacibaculum maritimum). Our results suggest that S. typhle is able to specifically prime the next generation against prevalent local bacteria and to a limited extent even also against newly introduced bacteria species. Long-term protection was thereby maintained only against prevailing Vibrio bacteria. Maternal and paternal transgenerational immune priming can complement each other, as they affect different pathways of the offspring immune system and come with distinct degree of specificity. The differential regulation of DNA-methylation genes upon parental bacteria exposure in premature pipefish offspring indicates that epigenetic regulation processes are involved in transferring immune-related information across generations. The identified trade-offs between immune priming and reproduction determine TGIP as a costly trait, which might constrain the evolution of long-lasting TGIP, if parental and offspring generations do not share the same parasite assembly.
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Biparental immune priming in the pipefish Syngnathus typhle.
Zoology, 2016Co-Authors: Anne Beemelmanns, Olivia RothAbstract:The transfer of immunity from parents to offspring (trans-generational immune priming (TGIP)) boosts offspring immune defence and parasite resistance. TGIP is usually a maternal trait. However, if fathers have a physical connection to their offspring, and if offspring are born in the paternal parasitic environment, evolution of paternal TGIP can become adaptive. In Syngnathus typhle, a sex-role reversed pipefish with male pregnancy, both parents invest into offspring immune defence. To connect TGIP with parental investment, we need to know how parents share the task of TGIP, whether TGIP is asymmetrically distributed between the parents, and how the maternal and paternal effects interact in case of biparental TGIP. We experimentally investigated the strength and differences but also the costs of maternal and paternal contribution, and their interactive biparental influence on offspring immune defence throughout offspring maturation. To disentangle maternal and paternal influences, two different bacteria were used in a fully reciprocal design for parental and offspring exposure. In offspring, we measured gene expression of 29 immune genes, 15 genes associated with epigenetic regulation, immune cell activity and life-history traits. We identified asymmetric maternal and paternal immune priming with a dominating, long-lasting paternal effect. We could not detect an additive adaptive biparental TGIP impact. However, biparental TGIP harbours additive costs as shown in delayed sexual maturity. Epigenetic regulation may play a role both in maternal and paternal TGIP.
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Female pipefish can detect the immune status of their mates
Behavioral Ecology and Sociobiology, 2015Co-Authors: Susanne H. Landis, Gunilla Rosenqvist, Josefin Sundin, Maude Poirier, Guro Øistensen Jørgensen, Olivia RothAbstract:Given the ubiquity of the parasites and their important fitness consequences on mate and offspring condition, selection for the ability to distinguish healthy from parasitized potential mates is a key process to enhance Darwinian fitness. In this study, we experimentally evaluated how the immunological experience of two potential partners influences mate choice, using the sex-role-reversed pipefish Syngnathus typhle . We exposed S. typhle to immune challenges with heat-killed Vibrio bacteria and investigated whether the activation of the immune system determined mate preferences. Our results demonstrate that the immune status of the potential partners influenced female mate preference, such that females that were exposed to an immune challenge became choosy and favored unchallenged males. Males, however, did not show any preferences for female immune status. In this context, we discuss mate choice decisions and behavioral plasticity as a complex result of immune challenge, severity of infection, as well as trans-generational effects.
