Originally, S. invicta was believed to be a red form of the black species S. saevissima richteri Forel. In 1972, Buren described the black imported fire ant to be a separate and distinct species, S. richteri Forel, and the RIFA was identified as S. invicta Buren (Hedges 1997).
Homologous recombination is a type of genetic recombination in which nucleotide (molecules which are joined make the structural units of RNA and DNA) sequences are exchanged between two similar or identical molecules of DNA.
Recombination is an integral part of the pairing of homologous chromosomes. It occurs between non-sister chromatids during the pachytene stage of meiosis I (the first stage of meiosis) and possibly before, when the homologous chromosomes are aligned in zygotene (Fig. 8.3).