Evidence of alloparental care during the incubation stage has largely been demonstrated for species that incubate their offspring externally in a nest. Alloparental care in these species generally consists of the rearing of mixed broods which contain a low proportion of “foreign” young alongside the host's own offspring. However, many animals, including sea anemones, incubate offspring either on or within their bodies. The beadlet anemone Actinia equina incubate their young internally, and as many sea anemones are capable of reproducing both sexually and asexually, the origin of these internally brooded young has been the subject of much debate. While genetically identical young are brooded internally under the juvenile stage, it is thought that those produced sexually are released as larvae into the water and must return to the gastric cavity of an adult in order for metamorphosis to occur. As the likelihood of a planula larva finding its way back to its parent is slim, this suggests that alloparental care may play a role in the survival of juveniles in this species, a hypothesis first suggested a century ago but rarely tested. Here, using highly polymorphic microsatellite markers, we find evidence of alloparental care in A. equina. Our results indicate that while a high proportion of juveniles were genetically identical to their brooding adult, the remaining juveniles showed stark genetic differences to their brooding adult. These juveniles shared far fewer alleles with their “parent” than expected under sexual reproduction, indicating that they were not the adult's offspring. Furthermore, we found variation in the genetic composition of broods, which consisted either of (a) entirely genetically identical individuals, (b) a mix of unique individuals and clonemates or (c) entirely unique individuals, that is no shared genotype. Our results thus indicate that adult A. equina tolerate the presence of non‐offspring within their gastric cavity and furthermore that they may incubate entirely “foreign” broods.

中文翻译：

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在内部繁殖的海葵中培育的证据

在孵化阶段对同种父母的照顾的证据已在很大程度上证明了其后代在巢中进行孵化的物种。这些物种的同父母育儿通常包括饲养混合的育雏，这些育雏中含有低比例的“外来”幼鱼以及寄主自己的后代。但是，包括海葵在内的许多动物都在其体内或体内孵化后代。该等指海葵海葵马尾由于内部有很多海葵能够繁殖有性和无性繁殖的海葵，因此这些内部繁殖的海葵的起源一直是许多争论的话题。虽然在幼年阶段内部繁殖了具有遗传同一性的幼仔，但人们认为，有性繁殖的幼仔会以幼虫的形式释放到水中，并且必须返回成年人的胃腔才能发生变态。由于扁平幼虫回到其母体的可能性很小，这表明同种异体的照料可能在该物种的幼体存活中起作用，这一假设在一个世纪前首次提出，但很少经过检验。在这里，使用高度多态的微卫星标记，我们发现了马科动物的同种异体护理的证据。。我们的结果表明，虽然在遗传上与其成年成年幼体相当的比例很高，但其余的幼体与其成年成年雌性却有着明显的遗传差异。这些少年与他们的“父母”所共有的等位基因比有性生殖时所预期的少得多，这表明它们不是该成年人的后代。此外，我们发现了育雏的遗传组成变异，其中包括（a）完全遗传相同的个体，（b）独特个体和克隆体的混合物，或（c）完全独特的个体，没有共同的基因型。因此，我们的结果表明，成年A.马能够耐受其子午线内非后代的存在，而且它们可能会完全孵化“外来”的雏鸟。