The Grey-backed Shrike parents adopt brood survival strategy in both the egg and nestling phases
The Grey-backed Shrike parents adopt brood survival strategy in both the egg and nestling phases
复制标题
灰背伯劳父母在卵和雏鸟阶段都采取巢生存策略
DOI：
10.1186/s40657-021-00244-x
复制
发表时间：
2021-03-09
期刊：
影响因子：
1.8
通讯作者：
Du, Bo
中科院分区：
文献类型：
--
作者：
Fan, Liqing;Gao, Lifang;Du, Bo
研究背景鸟类的养育方式存在着很大的多样性，长期以来，人们一直认为这是对特定环境条件的适应性反应，而不是对其生活史类型的适应性反应。方法对青藏高原灰背伯劳（Lanius tephronotus）一年一次繁殖的产卵和育雏规律进行研究。我们比较了其同域竞争对手，褐颊笑画眉（Trochalopteron henrici），每年繁殖两次的饮食组成。结果雌灰背伯劳的窝卵数固定为5窝，卵的大小随产蛋顺序而增加。最后一个在育雏的后代是不利的大小层次，因为它孵化后。然而，他们有最大的羽翼未丰的身体质量。这些结果表明，灰背伯劳在卵期和雏鸟期都采取了育雏生存策略。此外，男性和女性在提供父母照顾方面没有表现出性别分工，因为他们对交付给他们的育雏的食物总量做出了同等的贡献。灰背伯劳的这种养育模式，以及它们的饮食项目，与褐颊笑鸫的养育模式有很大的不同。结论我们认为，同域竞争者之间的生活史风格的分化，而不是对特定环境条件的行为反应，在驱动鸟类养育策略多样化中起着决定性的作用。
Background Great diversity exists in the parenting pattern of altricial birds, which has long been considered as an adaptive response to specific environmental conditions but not to their life-history style. Methods We examined the egg-laying and nestling-raising pattern of the Grey-backed Shrike (Lanius tephronotus) that breeds only once a year on the Tibetan Plateau. We compared the dietary composition to that of its sympatric competitor, the Brown-cheeked Laughing Thrush (Trochalopteron henrici) that breeds twice a year. Results Female Grey-backed Shrikes produced a fixed clutch size of five, with increasing egg size by their laying sequence. The last offspring in the brood is disadvantageous in the size hierarchy because it hatches later. However, they had the largest fledgling body mass. These findings indicate that Grey-backed Shrikes adopt the brood survival strategy in both the egg and nestling phases. Moreover, males and females exhibit no sexual division in providing parental care as they made an equal contribution to the total amount of food delivered to their brood. This parenting pattern of Grey-backed Shrikes, as well as their dietary items, differ significantly from those of the Brown-cheeked Laughing Thrush. Conclusions We suggest that the differentiation in life-history style between sympatric competitors, rather than a behavioral response to specific environmental conditions, plays a decisive role in driving avian parenting strategy diversification.