Smith Ashlee N, Creighton J Curtis, Belk Mark C
Biology Department, Brigham Young University, Provo, Utah, United States of America.
Department of Biological Sciences, Purdue University Northwest, Hammond, IN, United States of America.
PLoS One. 2017 Oct 31;12(10):e0186466. doi: 10.1371/journal.pone.0186466. eCollection 2017.
In species that require parental care, each parent can either care for their offspring or leave them in the care of the other parent. For each parent this creates three possible parental care strategies: biparental care, uniparental (male or female) care, and uniparental desertion by either the male or female. The burying beetle, Nicrophorus orbicollis, typically exhibits biparental care of offspring, and thus provides a unique system that allows us to compare the fitness benefits of these parental care strategies in an unconfounded way. In this study, we assess the lifetime fitness of biparental care, uniparental care, and uniparental desertion strategies in both male and female N. orbicollis. Specifically, we tested for increased fitness of the biparental care strategy compared to uniparental care strategies. Second, we test for equality of fitness between uniparental care and uniparental desertion strategies. Surprisingly, biparental care yields lower lifetime fitness for both parents compared to the other two strategies. Also, uniparental care and uniparental desertion strategies yielded equal fitness. The evolution of biparental care in this system is not consistent with the expectation of a mutual fitness benefit. We discuss other potential explanations for the evolution of biparental care in this system.
在需要亲代抚育的物种中，每个亲代可以选择照顾自己的后代，或者将它们留给另一方照顾。对于每个亲代来说，这产生了三种可能的亲代抚育策略：双亲抚育、单亲（雄性或雌性）抚育，以及雄性或雌性的单亲遗弃。埋葬虫（Nicrophorus orbicollis）通常表现出双亲对后代的抚育行为，因此提供了一个独特的系统，使我们能够以一种无混淆的方式比较这些亲代抚育策略的适合度益处。在这项研究中，我们评估了雄性和雌性埋葬虫中双亲抚育、单亲抚育和单亲遗弃策略的终生适合度。具体来说，我们测试了与单亲抚育策略相比，双亲抚育策略的适合度是否增加。其次，我们测试了单亲抚育和单亲遗弃策略之间适合度的平等性。令人惊讶的是，与其他两种策略相比，双亲抚育对双亲来说终生适合度都较低。此外，单亲抚育和单亲遗弃策略产生了相等的适合度。这个系统中双亲抚育的进化与相互适合度益处的预期不一致。我们讨论了这个系统中双亲抚育进化的其他潜在解释。
