Data from: An evaluation of the possible adaptive function of fungal brood covering by attine ants

Fungus-growing ants (Myrmicinae: Attini) live in an obligate symbiotic relationship with a fungus that they rear for food, but they can also use the fungal mycelium to cover their brood. We surveyed colonies from 20 species of fungus-growing ants and show that brood-covering behavior occurs in most species, but to varying degrees, and appears to have evolved shortly after the origin of fungus-farming, but was partly or entirely abandoned in some genera. To understand the evolution of the trait we used quantitative phylogenetic analyses to test whether brood covering behavior covaries among attine ant clades and with two hygienic traits that reduce risk of disease: mycelial brood cover did not correlate with mutualistic bacteria that the ants culture on their cuticles for their antibiotics, but there was a negative relationship between metapleural gland grooming and mycelial cover. A broader comparative survey showed that the pupae of many ant species have protective cocoons but that those in the subfamily Myrmicinae do not. We therefore evaluated the previously proposed hypothesis that mycelial covering of attine ant brood evolved to provide cocoon-like protection for the brood.植菌蚁（Myrmicinae: Attini）与供其培育取食的真菌形成专性共生关系，同时还可利用该真菌的菌丝体覆盖自身的子代。本研究针对20种植菌蚁的蚁群开展调查，结果显示子代覆盖行为在多数物种中均存在，但程度存在差异；该行为似乎在植菌习性起源后不久便逐步演化，但在部分蚁属中已被部分或完全舍弃。为解析该性状的演化历程，本研究采用定量系统发育分析方法，检验植菌蚁各演化支间的子代覆盖行为是否存在共演化模式，以及该行为与两种降低病害风险的卫生性状间的关联：结果表明，菌丝体子代覆盖行为与蚂蚁在表皮培育以获取抗生素的共生细菌并无相关性，但后胸侧板腺清洁行为与菌丝体覆盖程度呈负相关关系。一项更广泛的比较调查显示，多数蚂蚁物种的蛹具有保护性茧壳，但切叶蚁亚科（Myrmicinae）物种的蛹却无此结构。基于上述结果，本研究对此前提出的"植菌蚁子代的菌丝体覆盖行为是为子代提供类茧壳保护"这一假说进行了验证。