Consistent among-individual variation in behavior, or animal personality, is present in a wide variety of species. This behavioral variation is maintained by both genetic and environmental factors. Parental effects are a special case of environmental variation and are expected to evolve in populations experiencing large fluctuations in their environment. They represent a non-genetic pathway by which parents can transmit information to their offspring, by modulating their personality. While it is expected that parental effects contribute to the observed personality variation, this has rarely been studied in wild populations. We used the multimammate mouse Mastomys natalensis as a model system to investigate the potential effects of maternal personality on offspring behavior. We did this by repeatedly recording the behavior of individually housed juveniles which were born and raised in the lab from wild caught females. A linear correlation, between mother and offspring in behavior, would be expected when the personality is only affected by additive genetic variation, while a more complex relationship would suggests the presence of maternal effects. We found that the personality of the mother predicted the behavior of their offspring in a non-linear pattern. Exploration behavior of mother and offspring was positively correlated, but only for slow and average exploring mothers, while this correlation became negative for fast exploring mothers. This may suggests that early maternal effects could affect personality in juvenile M. natalensis, potentially due to density-dependent and negative frequency-dependent mechanisms, and therefore contribute to the maintenance of personality variation.

中文翻译：

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密度变化对啮齿动物物种的非线性母体影响

不同种类的动物在行为或动物性格方面存在一致的个体差异。遗传和环境因素都可以维持这种行为差异。父母的影响是环境变化的特例，并且预期其环境会发生很大的波动。它们代表了一种非遗传途径，父母可以通过这种途径通过调节其性格将信息传递给其后代。预计父母的影响会导致观察到的人格变异，但在野生种群中很少对此进行研究。我们使用了哺乳动物的纳塔氏菌作为一个模型系统来研究孕产妇性格对后代行为的潜在影响。为此，我们反复记录了在实验室中从野外捕获的雌性出生并长大的单独饲养的少年的行为。当人格仅受累加遗传变异影响时，可以预期母亲和后代的行为之间存在线性相关性，而更复杂的关系则表明存在母体效应。我们发现母亲的个性以非线性方式预测了他们的后代的行为。母亲和后代的探索行为呈正相关，但仅对于缓慢而普通的探索母亲而言，而这种相关对快速探索母亲则呈负相关。M.natalensis，可能归因于密度依赖性和负频率依赖性机制，因此有助于维持人格变异。