Department of Zoology, Faculty of Science, Charles University, CZ-12844 Prague, Czech Republic;
Department of Botany, Faculty of Science, Charles University, CZ-12801 Prague, Czech Republic.
Proc Natl Acad Sci U S A. 2019 Mar 26;116(13):6238-6243. doi: 10.1073/pnas.1810092116. Epub 2019 Mar 11.
Parental care behavior evolves to increase the survival of offspring. When offspring care becomes complicated for ecological reasons, cooperation of multiple individuals can be beneficial. There are two types of cooperative care: biparental care and worker (helper)-based care (e.g., eusociality). Although biparental care is common in several groups of vertebrates, it is generally rare in arthropods. Conversely, eusociality is widespread in insects, especially the aculeate Hymenoptera. Here, we present a case of biparental care in bees, in (Apidae, Xylocopinae). Similar to eusocial behavior, biparental care leads to greater brood protection in this species. Male guarding increases provisioning of nests because females are liberated from the tradeoff between provisioning and nest protection. The main benefit of parental care for males should be increased paternity. Interestingly though, we found that paternity of offspring by guard males is extraordinarily low (10% of offspring). Generally, we found that nests were not guarded by the same male for the whole provisioning season, meaning that males arrive to nests as stepfathers. However, we show that long-term guarding performed by a single male does increase paternity. We suggest that the multiple-mating strategy of these bees increased the amount of time for interactions between the sexes, and this longer period of potential interaction supported the origin of biparental care. Eusociality based on monandry was thought to be the main type of extended brood protection in bees. We show that biparental care based on polyandry provides an interesting evolutionary alternative.
亲代照顾行为的进化是为了提高后代的存活率。当后代照顾因生态原因变得复杂时，多个个体的合作可能是有益的。有两种类型的合作照顾：双亲照顾和工蜂（帮手）为基础的照顾（例如，真社会性）。虽然双亲照顾在几个脊椎动物群体中很常见，但在节肢动物中通常很少见。相反，真社会性在昆虫中很普遍，尤其是刺状膜翅目。在这里，我们介绍了一种在蜜蜂（Apidae，Xylocopinae）中的双亲照顾行为。与真社会性行为类似，双亲照顾导致该物种中更多的幼体保护。雄性的守护增加了巢穴的供应，因为雌性不再需要在供应和巢穴保护之间进行权衡。雄性进行亲代照顾的主要好处应该是增加父权。然而，有趣的是，我们发现守护雄性后代的父权率极低（10%的后代）。通常，我们发现巢穴不会由同一只雄性守护整个供应季节，这意味着雄性作为继父进入巢穴。然而，我们表明，由单一雄性进行的长期守护确实会增加父权。我们认为，这些蜜蜂的多配偶交配策略增加了雌雄之间相互作用的时间，而这种更长的潜在相互作用期支持了双亲照顾的起源。基于单配偶制的真社会性被认为是蜜蜂中扩展幼体保护的主要类型。我们表明，基于多配偶制的双亲照顾提供了一个有趣的进化替代方案。
