College of Science, Ibaraki University, , Mito, Ibaraki 310-8512, Japan.
Biol Lett. 2011 Apr 23;7(2):257-60. doi: 10.1098/rsbl.2010.0856. Epub 2010 Oct 27.
A number of social insect species have recently been shown to have genetically influenced caste determination (GCD), challenging the conventional view that caste determination should be strictly environmental. To date, GCD has been found in phylogenetically isolated species; examples of GCD being present in multiple species of a genus are lacking. Through crossing experiments of neotenic (juvenile) reproductives, we have recently provided the first evidence for a royal versus worker GCD in the termite Reticulitermes speratus. To elucidate whether this system is more widespread, we performed crossing experiments using three additional Reticulitermes species. Offspring caste and sex ratios were found to be highly similar to those found previously in R. speratus, raising the possibility that GCD was present in an ancestral lineage of Reticulitermes, and subsequently maintained throughout several episodes of speciation.
一些社会昆虫物种最近被证明具有遗传影响的级型分化（GCD），这挑战了级型分化应该严格受环境影响的传统观点。迄今为止，GCD 已在系统发育上孤立的物种中发现；在一个属的多个物种中存在 GCD 的例子很少。通过对幼态生殖个体的杂交实验，我们最近在白蚁 Reticulitermes speratus 中提供了第一个关于皇家与工蚁 GCD 的证据。为了阐明这个系统是否更为普遍，我们使用另外三个 Reticulitermes 物种进行了杂交实验。发现后代的级型和性别比例与之前在 R. speratus 中发现的非常相似，这增加了 GCD 存在于 Reticulitermes 祖先谱系中的可能性，随后在几次物种形成过程中得以维持。
