The evolution of multicellularity has been one of the major transitions in the history of life. In contrast to animals and plants, how multicellularity evolved in fungi and how it compares to the general principles distilled from the study of more widely studied model systems, has received little attention. This review broadly discusses multicellular functioning and evolution in fungi. We focus on how fungi solved some of the common challenges associated with the evolution of multi-celled organisms and what unique challenges follow from the peculiar, filamentous growth form of fungi. We identify and discuss seven key challenges for fungal multicellular growth: apical growth, compartmentalization, long-distance mass transport, controlling mutational load, cell-to-cell communication, differentiation and adhesion. Some of these are characteristic of all multicellular transitions, whereas others are unique to fungi. We hope this review will facilitate the interpretation of fungal multicellularity in comparison with that of other multicellular lineages and will prompt further research into how fungi solved fundamental challenges in one of the major transitions in their evolutionary history.

多细胞性的进化一直是生活史上的主要转变之一。与动植物相反，真菌中的多细胞性如何进化，以及如何与从更广泛研究的模型系统的研究中提炼出来的一般原理相比较，很少受到关注。这篇综述广泛地讨论了真菌中的多细胞功能和进化。我们专注于真菌如何解决与多细胞生物进化相关的一些常见挑战，以及独特的丝状生长形式的真菌带来了哪些独特的挑战。我们确定并讨论了真菌多细胞生长的七个关键挑战：顶端生长，分隔，长距离质量运输，控制突变负荷，细胞间通信，分化和粘附。其中一些是所有多细胞转换的特征，而其他则是真菌特有的。我们希望，与其他多细胞谱系相比，本综述将有助于真菌多细胞性的解释，并将促使人们进一步研究真菌如何解决其进化史上的主要转变之一中的基本挑战。