@article{10166,
  abstract     = {While sexual reproduction is widespread among many taxa, asexual lineages have repeatedly evolved from sexual ancestors. Despite extensive research on the evolution of sex, it is still unclear whether this switch represents a major transition requiring major molecular reorganization, and how convergent the changes involved are. In this study, we investigated the phylogenetic relationship and patterns of gene expression of sexual and asexual lineages of Eurasian Artemia brine shrimp, to assess how gene expression patterns are affected by the transition to asexuality. We find only a few genes that are consistently associated with the evolution of asexuality, suggesting that this shift may not require an extensive overhauling of the meiotic machinery. While genes with sex-biased expression have high rates of expression divergence within Eurasian Artemia, neither female- nor male-biased genes appear to show unusual evolutionary patterns after sexuality is lost, contrary to theoretical expectations.},
  author       = {Huylmans, Ann K and Macon, Ariana and Hontoria, Francisco and Vicoso, Beatriz},
  issn         = {1471-2954},
  journal      = {Proceedings of the Royal Society B: Biological Sciences},
  keywords     = {asexual reproduction, parthenogenesis, sex-biased genes, sexual conflict, automixis, crustaceans},
  number       = {1959},
  publisher    = {The Royal Society},
  title        = {{Transitions to asexuality and evolution of gene expression in Artemia brine shrimp}},
  doi          = {10.1098/rspb.2021.1720},
  volume       = {288},
  year         = {2021},
}

@article{1993,
  abstract     = {The fitness effects of symbionts on their hosts can be context-dependent, with usually benign symbionts causing detrimental effects when their hosts are stressed, or typically parasitic symbionts providing protection towards their hosts (e.g. against pathogen infection). Here, we studied the novel association between the invasive garden ant Lasius neglectus and its fungal ectosymbiont Laboulbenia formicarum for potential costs and benefits. We tested ants with different Laboulbenia levels for their survival and immunity under resource limitation and exposure to the obligate killing entomopathogen Metarhizium brunneum. While survival of L. neglectus workers under starvation was significantly decreased with increasing Laboulbenia levels, host survival under Metarhizium exposure increased with higher levels of the ectosymbiont, suggesting a symbiont-mediated anti-pathogen protection, which seems to be driven mechanistically by both improved sanitary behaviours and an upregulated immune system. Ants with high Laboulbenia levels showed significantly longer self-grooming and elevated expression of immune genes relevant for wound repair and antifungal responses (β-1,3-glucan binding protein, Prophenoloxidase), compared with ants carrying low Laboulbenia levels. This suggests that the ectosymbiont Laboulbenia formicarum weakens its ant host by either direct resource exploitation or the costs of an upregulated behavioural and immunological response, which, however, provides a prophylactic protection upon later exposure to pathogens. },
  author       = {Konrad, Matthias and Grasse, Anna V and Tragust, Simon and Cremer, Sylvia},
  issn         = {1471-2954},
  journal      = {Proceedings of the Royal Society of London Series B Biological Sciences},
  number       = {1799},
  publisher    = {The Royal Society},
  title        = {{Anti-pathogen protection versus survival costs mediated by an ectosymbiont in an ant host}},
  doi          = {10.1098/rspb.2014.1976},
  volume       = {282},
  year         = {2015},
}

@article{2853,
  abstract     = {High relatedness among interacting individuals has generally been considered a precondition for the evolution of altruism. However, kin-selection theory also predicts the evolution of altruism when relatedness is low, as long as the cost of the altruistic act is minor compared with its benefit. Here, we demonstrate evidence for a low-cost altruistic act in bacteria. We investigated Escherichia coli responding to the attack of an obligately lytic phage by committing suicide in order to prevent parasite transmission to nearby relatives. We found that bacterial suicide provides large benefits to survivors at marginal costs to committers. The cost of suicide was low, because infected cells are moribund, rapidly dying upon phage infection, such that no more opportunity for reproduction remains. As a consequence of its marginal cost, host suicide was selectively favoured even when relatedness between committers and survivors approached zero. Altogether, our findings demonstrate that low-cost suicide can evolve with ease, represents an effective host-defence strategy, and seems to be widespread among microbes. Moreover, low-cost suicide might also occur in higher organisms as exemplified by infected social insect workers leaving the colony to die in isolation.},
  author       = {Refardt, Dominik and Bergmiller, Tobias and Kümmerli, Rolf},
  issn         = {1471-2954},
  journal      = {Proceedings of the Royal Society of London Series B Biological Sciences},
  number       = {1759},
  publisher    = {The Royal Society},
  title        = {{Altruism can evolve when relatedness is low: Evidence from bacteria committing suicide upon phage infection}},
  doi          = {10.1098/rspb.2012.3035},
  volume       = {280},
  year         = {2013},
}