Probing termite social systems through allozyme and mtDNA analysis: a case study of Nasutitermes nigriceps and Nasutitermes costalis (Isoptera, Termitidae)

摘要

Certain termite genera exhibit a high degree of variation with respect to the number and developmental origin of reproductives within single colonies. Although such variation is expected to influence patterns of intracolonial competition and cooperation, it has thus far been difficult to investigate. This study exploits both allozyme and mtDNA analysis of colony offspring to infer the reproductive composition of single colonies. This study focuses on two species of Nasutitermes which differ in their social structure: colonies of N. nigriceps are generally led by a single mated pair, while those of N. costalis are regularly polygamous. MtDNA analysis on N. nigriceps showed that all colony members share the same haplotype, even in those cases whereallozyme genotype frequencies suggest that colony offspring are derived from more than one reproductive pair. Similar work on N. costalis revealed a complete lack of mtDNA and allozyme variation. It is discussed how breeding system shifts from monogamy to polygamy in termites may be facilitated by population bottlenecks which reduce genetic diversity.