As the use of functional trait approaches is growing in fungal ecology, there is a corresponding need to understand trait variation. Much of trait theory and statistical techniques are built on the assumption that interspecific variation is larger than intraspecific variation. This allows the use of mean trait values for species, which the vast majority of trait studies adopt. We examined the size of intra- vs. inter-specific variation in two wood fungal fruit body traits: size and density. Both coefficients of variation (CV) and Trait Probability Density analyses were used to quantify trait variation. We found that intraspecific variation in fruit body density was more than twice as variable as interspecific variation, and fruit body size was hugely variable (CVs averaged 190%), although interspecific variation was larger. Further, there was a very high degree of overlap in the trait space of species, indicating that there may be little niche partitioning at the species level. These findings show that intraspecific variation is highly important and should be accounted for when using trait approaches to understand fungal ecology. More data on variation of other fungal traits is also desperately needed to ascertain whether the high level of variation found here is typical for fungi. While the need to measure individuals does reduce the ability to generalise at the species level, it does not negate the usefulness of fungal trait measurements. There are two reasons for this: first, the ecology of most fungal species remains poorly known and trait measurements address this gap; and secondly, if trait overlap between species more generally is as much as we found here, then individual measurements may be more helpful than species identity for untangling fungal community dynamics.

在真菌生态学中，随着功能性状方法的使用不断增长，相应地需要了解性状变异。许多性状理论和统计技术都建立在种间变异大于种内变异的假设之上。这允许使用物种的平均特征值，绝大多数特征研究都采用该值。我们研究了两种木耳真菌果实的性状：种内和种间变异的大小：大小和密度。变异系数（CV）和性状概率密度分析均用于量化性状变异。我们发现，种内密度的种内变异是种间变异的两倍多，而种间变异较大（CV平均为190％），尽管种间变异较大。进一步，物种的性状空间有非常高度的重叠，这表明物种水平上的生态位分配可能很少。这些发现表明种内变异非常重要，在使用性状方法了解真菌生态学时应予以考虑。还迫切需要更多有关其他真菌性状变异的数据，以确定此处发现的高水平变异是否是真菌的典型特征。尽管测量个体的需求确实降低了在物种水平上进行概括的能力，但这并没有否定真菌性状测量的有用性。造成这种情况的原因有两个：第一，大多数真菌物种的生态学仍然鲜为人知，而性状测量可以弥补这一差距。其次，如果物种之间的性状重叠更普遍，正如我们在这里发现的那样，