Enzmann B L, Nonacs P
Department of Ecology and Evolutionary Biology, University of California, Los Angeles, 621 Charles E. Young Drive South, Los Angeles, CA 90095 USA.
Insectes Soc. 2010 Feb;57(1):115-123. doi: 10.1007/s00040-009-0056-7. Epub 2009 Dec 20.
Ants exhibit a size-associated colony founding trait that is characterized by the degree to which foundresses rely on internal reserves to raise their first brood of workers (claustrality). The reliance on stored reserves is positively correlated with degree of claustrality (claustral > facultative > semi-claustral) and is variable across species of Pogonomyrmex harvester ants. Three species of harvester ant foundresses that differ in degree of claustrality were observed initiating nests under laboratory conditions over 2 years. P. rugosus is fully claustral, P. salinus is facultative, and P. californicus is semi-claustral. Across species, degree of claustrality was positively associated with mean digging rate and nest depth over the first 3 days of nest initiation, total nest depth, and degree of nest closure. Branching and abundance of peripheral nodes were higher in semi-claustral and facultative nests than in claustral nests. The facultative species dug for the longest time and achieved the greatest tunnel length. Within each species, there were trends associating mass with digging rate, but these were not consistent in all species. There were no intraspecific trends of mass with nest depth. Also within species, a foundress's mass did not affect her tendency to open or close her nest. These results reveal degree of claustrality is correlated across species with several nest initiation characteristics that together may represent different colony founding syndromes.
蚂蚁表现出一种与体型相关的建巢特征，其特点是蚁后依靠内部储备来养育第一批工蚁的程度（闭巢性）。对储存储备的依赖程度与闭巢性程度呈正相关（完全闭巢 > 兼性闭巢 > 半闭巢），并且在收获蚁属（Pogonomyrmex）的不同物种中有所不同。在两年多的实验室条件下，观察到三种闭巢性程度不同的收获蚁蚁后开始筑巢。皱纹收获蚁（P. rugosus）是完全闭巢的，盐收获蚁（P. salinus）是兼性闭巢的，而加州收获蚁（P. californicus）是半闭巢的。在所有物种中，闭巢性程度与筑巢开始的前三天的平均挖掘速度、巢深度、总巢深度以及巢封闭程度呈正相关。半闭巢和兼性闭巢的巢中，周边节点的分支和丰度比完全闭巢的巢更高。兼性闭巢的物种挖掘时间最长，挖掘的隧道长度也最长。在每个物种内部，存在体型与挖掘速度相关的趋势，但并非在所有物种中都一致。不存在体型与巢深度的种内趋势。同样在物种内部，蚁后的体型并不影响其打开或封闭巢穴的倾向。这些结果表明，闭巢性程度在不同物种间与几种筑巢开始特征相关，这些特征共同可能代表不同的建巢综合征。
