Biology subjects

Radzvilavicius, A.

Publications and source records attributed to Radzvilavicius, A..

2 recordsLinked to original sources

bioRxiv2018

Evolution of empathetic moral evaluation

Social norms can promote cooperation in human societies by assigning reputations to individuals based on their past actions. A good reputation indicates that an individual is worthy of help and is likely to reciprocate. A large body of research has established the norms of moral assessment that promote cooperation and maximize social welfare, assuming reputations are objective. But if there is no centralized institution to provide objective moral evaluation, then opinions about an individuals reputation may differ across a population. Here we use evolutionary game theory to study the effects of empathy - the capacity to make moral evaluations from the perspective of another person. We find that empathetic moral evaluation tends to foster cooperation by reducing the rate of unjustified defection. The norms of moral evaluation previously considered most socially beneficial depend on high levels of empathy, whereas different norms are required to maximize social welfare in populations unwilling or incapable of empathy. We demonstrate that empathy itself can evolve through social contagion and attain evolutionary stability under most social norms. We conclude that a capacity for empathetic moral evaluation represents a key component to sustaining cooperation in human societies: cooperation requires getting into the mindset of others whose views differ from our own.

evolutionary biology↗

bioRxiv2017

Mitigating Mitochondrial Genome Erosion Without Recombination

Mitochondria are ATP-producing organelles of bacterial ancestry that played a key role in the origin and early evolution of complex eukaryotic cells. Most modern eukaryotes transmit mitochondrial genes uniparentally, often without recombination among genetically divergent organelles. While this asymmetric inheritance maintains the efficacy of purifying selection at the level of the cell, the absence of recombination could also make the genome susceptible to Mullers ratchet. How mitochondria escape this irreversible defect accumulation is a fundamental unsolved question. Occasional paternal leakage could in principle promote recombination, but it would also compromise the purifying-selection benefits of uniparental inheritance. We assess this tradeoff using a stochastic population-genetic model. In the absence of recombination, uniparental inheritance of freely segregating genomes mitigates mutational erosion, while paternal leakage exacerbates the ratchet effect. Mitochondrial fusion-fission cycles ensure independent genome segregation, improving purifying selection. Paternal leakage provides opportunity for recombination to slow down the mutation accumulation, but always at a cost of increased steady-state mutation load. Our findings indicate that random segregation of mitochondrial genomes under uniparental inheritance can effectively combat the mutational meltdown, and that homologous recombination under paternal leakage might not be needed.

genetics↗