It is suggested that a “genetic cleansing” of recognition cues occurred after introduction of the Argentine ant, which resulted in the formation of two immense supercolonies, one of which effectively forms the largest cooperative unit ever recorded.
The computer program matesoft offers both newly developed algorithms for inferring maternal and paternal genotypes, and integrated estimation and correction procedures for calculating mating frequency statistics.
Three methods to solve the identification of colonies problem are presented: rare genotype sisterhoods, G -distance (a measure of genotypic heterogeneity derived from G -statistics), and neighbour relatedness (estimates of genetic relatedness for specific nest pairs).
It is argued that inclusive fitness theory has been of little value in explained the natural world, and that it has led to negligible progress in explaining the evolution of eusociality, but these arguments are based upon a misunderstanding of evolutionary theory and a misrepresentation of the empirical literature.
It is found that native populations also form supercolonies, and are effectively unicolonial, just as in introduced populations, and the relatedness between nestmates is not distinguishable from zero in these native range supercolony.
Both primary introductions and secondary introductions were important in the global expansion of the Argentine ant and indicates that invasiveness did not evolve recently as a unique and historically contingent event (e.g. reduction of genetic diversity) in this species.
All joint evidence supports the inference that the 14 introduced populations of L. neglectus in Europe likely arose from only very few independent introductions from the native range, and that new infestations were typically started through Introductions from other invasive populations.
This study examines the social and genetic structure of colonies in the polygynous ant Myrmica sulcinodis and suggests that a special class of queen ‘floaters’ only stays ephemerally in the colonies, thus causing a substantial turnover of reproducing queens across years.
It is concluded that multiple paternity in M. sulcinodis did not evolve as an adaptation to increase genetic variation within colonies, and that moderate degrees of multiple mating may be an unselected consequence of mating at low cost when mating occurs close to the nest and mating in swarms with a highly male biased operational sex ratio.
The results challenge the notion that supercolonial organization is an inevitable consequence of low genetic variation for chemical recognition cues in small invasive founder populations and infer that low variation and limited volatility in cuticular hydrocarbon profiles already existed in the native range in combination with low dispersal and a highly viscous population structure.