SSA: The evolution of cooperation in an arid-zone bird: bet-hedging, plasticity and constraints

解释合作的进化（以牺牲自己为代价造福他人的行为）是进化和机械生物学的一个关键挑战。虽然人们早就认识到，合作行为可能会产生间接的健身效益的演员，通过增加相关育种的繁殖成功，在该领域的最新进展突出了几个潜在的并发症，在实践中测试这一想法。首先，合作行为实际上可能会产生间接的健身效益，压缩相关育种繁殖成功的方差。第二，合作行为对相关母亲的生殖成功的影响可能被母亲对合作者的存在的先发制人的反应所掩盖（例如，母亲可能会减少对后代的产前投资，当他们预期接受合作的产后护理时）。第三，研究得最多的动物合作形式（异亲照顾;为他人的后代提供照顾）的进化可能受到与父母照顾的遗传相关性的限制。在这篇论文中，我们利用长期的生活史和高密度的基因组数据从野生喀拉哈里麻雀织社会提供最强有力的支持，以日期为这些现象，揭示了他们的潜在重要性，在塑造合作的演变。

Explaining the evolution of cooperation (behaviour that benefits others at a cost to self) is a key challenge in evolutionary and mechanistic biology. While it has long been recognised that cooperative behaviour may yield indirect fitness benefits to actors by increasing the reproductive success of related breeders, recent advances in the field have highlighted several potential complications with testing this idea in practice. First, cooperative behaviour may actually yield indirect fitness benefits by compressing variance in the reproductive success of related breeders. Second, the effects of cooperative behaviour on the reproductive success of related mothers may be shrouded by pre-emptive maternal responses to the presence of co-operators (e.g. mothers may reduce their pre-natal investment in offspring when they anticipate receiving cooperative post-natal care for their young). Third, the evolution of the best-studied form of animal cooperation (alloparental care; the provision of care to the offspring of others) could be constrained by genetic correlations with parental care. In this thesis we utilise long-term life-history and high density genomic data from wild Kalahari sparrow-weaver societies to provide the strongest support to date for each of these phenomena, shedding new light on their potential importance in shaping the evolution of cooperation.