Bulmer Mark S, Franco Bruno A, Fields Edith G
Department of Biological Sciences, Towson University, 341 Smith Hall, 8000 York Rd., Towson, MD 21252, USA.
Towson High School, 69 Cedar Ave, Towson, MD 21286, USA.
Insects. 2019 Aug 5;10(8):240. doi: 10.3390/insects10080240.
In social insects, alerting nestmates to the presence of a pathogen should be critical for limiting its spread and initiating social mechanisms of defense. Here we show that subterranean termites use elevated vibratory alarm behavior to help prevent fatal fungal infections. The elevated alarm leads to elevated social hygiene. This requires that termites coalesce so that they can groom each other's cuticular surfaces of contaminating conidial spores. Groups of 12 workers varied in their response when immersed in conidia solutions of nine different strains of . Pathogen alarm displays of short 2-7-second bursts of rapid longitudinal oscillatory movement (LOM), observed over 12 min following a fungal challenge, were positively correlated with the time that workers spent aggregated together grooming each other. The frequency of these LOMs was inversely correlated with fatal fungal infections. The variation in fatalities appeared to be largely attributable to a differential response to and in the time spent in aggregations and the frequency of allogrooming. Isolated workers challenged with conidia did not display LOMs, which suggests that the alarm is a conditional social response. LOMs appear to help signal the presence of fungal pathogens whose virulence depends on the level of this emergency alert.
在群居昆虫中，向巢伴警示病原体的存在对于限制其传播以及启动社会防御机制至关重要。在此我们表明，地下白蚁利用增强的振动警报行为来帮助预防致命的真菌感染。增强的警报会带来更高的社会卫生水平。这要求白蚁聚集在一起，以便它们能够相互梳理被污染的分生孢子的表皮表面。当12只工蚁群体浸入9种不同菌株的分生孢子溶液中时，它们的反应各不相同。在受到真菌攻击后的12分钟内观察到的持续2 - 7秒的快速纵向振荡运动（LOM）的病原体警报表现，与工蚁聚集在一起相互梳理的时间呈正相关。这些LOM的频率与致命真菌感染呈负相关。死亡情况的差异似乎很大程度上归因于对不同菌株在聚集时间和异体梳理频率上的不同反应。受到分生孢子攻击的孤立工蚁没有表现出LOM，这表明警报是一种有条件的社会反应。LOM似乎有助于发出毒力取决于这种紧急警报水平的真菌病原体存在的信号。
