Phenotypic variance, plasticity and heritability estimates of critical thermal limits depend on methodological context
Phenotypic variance, plasticity and heritability estimates of critical thermal limits depend on methodological context
复制标题
DOI：
10.1111/j.1365-2435.2008.01481.x
复制
发表时间：
2009-02-01
影响因子：
5.2
通讯作者：
Terblanche, John S.
中科院分区：
文献类型：
--
作者：
Chown, Steven L.;Jumbam, Keafon R.;Terblanche, John S.
生物学家长期以来一直关注测量热性能曲线和极限，因为它们对健身具有重要意义。基本的实验设计可能会对此类测量的结果产生显着影响，尤其是在评估活动的临界热极限期间使用的温度变化的实验速率。迄今为止，工作的重点几乎完全集中在速率变异对临界限值平均值的影响上。如果实验中使用的温度变化速率不仅影响性状平均值而且还影响其方差，那么遗传变异的估计也会受到深刻影响。此外，如果驯化的结果同样受到方法论方法的影响，对有益驯化和其他假设的评估也可能会受到影响。在本文中，我们使用模型物种果蝇和入侵蚂蚁物种 Linepithema humile 的种群确定了临界温度限制是否属于这种情况。我们发现，不同温度变化率的影响在性状和物种之间存在差异。然而，一般来说，假设遗传方差保持不变，不同的温度变化率会导致不同的表型方差和不同的遗传力估计。我们还发现，不同的速率导致了关于物种对驯化的反应的不同结论，特别是在 L. humile 的情况下。尽管现在否认过去关于临界温度限制的种间和驯化相关变化的普遍性似乎还为时过早，但我们建议适当选择试验期间的条件，仔细报告并严格控制。
Biologists have long been concerned with measuring thermal performance curves and limits because of their significance to fitness. Basic experimental design may have a marked effect on the outcome of such measurements, and this is true especially of the experimental rates of temperature change used during assessments of critical thermal limits to activity. To date, the focus of work has almost exclusively been on the effects of rate variation on mean values of the critical limits.If the rate of temperature change used in an experimental trial affects not only the trait mean but also its variance, estimates of heritable variation would also be profoundly affected. Moreover, if the outcomes of acclimation are likewise affected by methodological approach, assessment of beneficial acclimation and other hypotheses might also be compromised.In this article, we determined whether this is the case for critical thermal limits using a population of the model species Drosophila melanogaster and the invasive ant species Linepithema humile.We found that effects of the different rates of temperature change are variable among traits and species. However, in general, different rates of temperature change resulted in different phenotypic variances and different estimates of heritability, presuming that genetic variance remains constant. We also found that different rates resulted in different conclusions regarding the responses of the species to acclimation, especially in the case of L. humile.Although it seems premature to dismiss past generalities concerning interspecific and acclimation-related variation in critical thermal limits, we recommend that conditions during trials be appropriately selected, carefully reported and rigorously controlled.