Field Jeremy
Centre for Ecology and Conservation, University of Exeter, Penryn, Cornwall TR10 9EZ, UK.
Philos Trans R Soc Lond B Biol Sci. 2025 Mar 20;380(1922):20230265. doi: 10.1098/rstb.2023.0265.
The evolution of primitive eusociality from non-social ancestors in organisms such as bees and wasps is often regarded as a major evolutionary transition. The division of labour between reproductives that specialize on egg production and workers that specialize on tasks such as foraging is the key feature defining eusociality and is why social insects are so successful ecologically. In taxa with morphological castes, individuals are often irreversibly specialized for particular roles when they reach adulthood. At the origin of sociality, however, such adaptations were absent, and we must consider why selection would favour individuals specializing when they are undifferentiated from the ancestral, non-social phenotype. Here, I focus on constraints based on life-history tradeoffs and plasticity that would be faced by ancestral females when specializing. These include limited efficiency of within-individual tradeoffs between reproductive and worker functions, imperfect matching of the productivities of social partners and lack of coordination. I also discuss the possibility that payoffs through specialization could be condition dependent. Eusocial taxa lacking morphological castes have traditionally been the testing grounds to understand the origin of eusociality, but significant adaptation has occurred since helping first evolved. Investigating role specialization at the origin of eusociality therefore requires utilizing non-social taxa.This article is part of the theme issue 'Division of labour as key driver of social evolution'.
在蜜蜂和黄蜂等生物中，从非社会性祖先演化出原始的真社会性通常被视为一次重大的进化转变。专门负责产卵的繁殖者与专门从事觅食等任务的工蜂之间的分工，是界定真社会性的关键特征，也是社会性昆虫在生态上如此成功的原因。在具有形态等级的分类群中，个体成年后往往会不可逆转地专门从事特定角色。然而，在社会性起源之时，并不存在这样的适应性变化，我们必须思考为什么选择会青睐那些与祖先的非社会性表型没有差异的个体进行专门化。在此，我关注基于生活史权衡和可塑性的限制因素，这些是祖先雌性在进行专门化时可能面临的。这些因素包括个体在繁殖功能和工蜂功能之间进行权衡的效率有限、社会伙伴生产力的不完全匹配以及缺乏协调性。我还讨论了通过专门化获得的收益可能取决于条件的可能性。传统上，缺乏形态等级的真社会性分类群一直是理解真社会性起源的试验场，但自从帮助行为首次出现以来，已经发生了显著的适应性变化。因此，研究真社会性起源时的角色专门化需要利用非社会性分类群。本文是主题为“分工是社会进化的关键驱动力”的一部分。
