Data from: A synthesized framework for the evolutionary origins of obligate avian brood parasitism

The repeated evolution of obligate avian brood parasitism (OBP) across diverse lineages represents a major evolutionary puzzle. While host-parasite coevolution has been extensively studied, the initial conditions that favor OBP emergence remain unclear. Here, we integrate theoretical modeling, paleoclimate mapping, and phylogenetic comparative analyses to identify the key drivers underlying OBP evolution. Our model demonstrates that rising parental care costs, particularly under environmental stress, favor the emergence of OBP. However, its persistence requires additional life-history adaptations, including increased offspring production. Paleoclimatic data support this framework: OBP origins often followed major climatic upheavals, with fixations occurring during subsequently more stable periods. Phylogenetic analyses reveal that OBP evolution is associated with high-mortality ecological traits, such as open-habitat use. We also find increased OBP likelihood in both smaller carnivorous and larger herbivorous/omnivorous species, indicating size-dependent trophic constraints. These results provide a unified framework explaining the recurrent evolution of OBP by linking environmental pressures and life-history trade-offs to this remarkable behavioral adaptation.专性鸟类育雏寄生（Obligate Avian Brood Parasitism, OBP）在多个演化支中的反复演化，是演化生物学领域的一大核心谜题。尽管宿主与寄生者的协同演化已被广泛研究，但促使OBP出现的初始条件仍未明确。本研究整合理论建模、古气候制图与系统发育比较分析方法，旨在阐明OBP演化背后的核心驱动因素。我们的模型显示，亲本抚育成本的攀升——尤其是在环境胁迫条件下——会推动OBP的出现。但OBP的持续存续则需要额外的生活史适应性演化，例如提高后代繁殖量。古气候数据佐证了这一理论框架：OBP的起源往往紧随重大气候剧变，而该性状的种群固定则发生在后续更为稳定的时期。系统发育分析结果表明，OBP的演化与高死亡率生态特征（如开放生境利用）存在关联。我们还发现，体型较小的肉食性鸟类与体型较大的植食性/杂食性鸟类中，OBP的出现概率均有所提升，这表明存在体型依赖的营养级约束。本研究结果构建了统一的理论框架，通过将环境压力、生活史权衡与这一非凡的行为适应性相联结，解释了OBP反复演化的现象。