LAGE do Departamento de Ecologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, travessa 14, n° 101, Cid. Universitária, 05508-090, São Paulo, Brazil.
BECO do Departamento de Zoologia, Instituto de Biociências, Universidade de São Paulo, Rua do Matão, travessa 14, n° 101, Cid. Universitária, 05508-090, São Paulo, Brazil.
Biol Rev Camb Philos Soc. 2017 Aug;92(3):1688-1701. doi: 10.1111/brv.12303. Epub 2016 Oct 10.
The intensity of biotic interactions varies around the world, in such a way that mortality risk imposed by natural enemies is usually higher in the tropics. A major role of offspring attendance is protection against natural enemies, so the benefits of this behaviour should be higher in tropical regions. We tested this macroecological prediction with a meta-regression of field experiments in which the mortality of guarded and unguarded broods was compared in arthropods. Mortality of unguarded broods was higher, and parental care was more beneficial, in warmer, less seasonal environments. Moreover, in these same environments, additional lines of defence further reduced offspring mortality, implying that offspring attendance alone is not enough to deter natural enemies in tropical regions. These results help to explain the high frequency of parental care among tropical species and how biotic interactions influence the occurrence of parental care over large geographic scales. Finally, our findings reveal that additional lines of defences - an oftentimes neglected component of parental care - have an important effect on the covariation between the benefits of parental care and the climate-mediated mortality risk imposed by natural enemies.
生物相互作用的强度在世界各地有所不同，以至于在热带地区，天敌造成的死亡率通常更高。后代照料的主要作用是防止天敌的侵害，因此这种行为的好处在热带地区应该更高。我们通过对节肢动物的野外实验进行荟萃回归来检验这一宏观生态学预测，在这些实验中，比较了有保护和无保护的雏鸡的死亡率。在温暖、季节性较弱的环境中，无保护的雏鸡死亡率更高，亲代照顾的好处更大。此外，在这些相同的环境中，额外的防御线进一步降低了后代的死亡率，这意味着仅靠后代照料不足以阻止热带地区的天敌。这些结果有助于解释热带物种中亲代照顾的高频率以及生物相互作用如何在大地理尺度上影响亲代照顾的发生。最后，我们的研究结果表明，额外的防御线（通常被忽视的亲代照顾的一个组成部分）对亲代照顾的好处与天敌造成的气候介导的死亡率风险之间的协变有重要影响。
