Evolutionary discontinuity of the Carabine ground beetles

The Carabine ground beetles are mostly hind wing-less and cannot fly, so th at there is more chance of diversification by geographic isolation compared with winged insects. The relationships between morphological diversificati on and phylogeny of the ground beetles of the world have been inferred main ly by comparisons of mitochondrial ND5 gene sequences. Based on dating by a mitochondrial DNA "clock," it has been deduced that an explosive radiation of the major carabine groups took place 50-40 MYA. This was followed by oc casional radiations on various scales, sometimes accompanied by parallel mo rphological changes. There are also a good number of examples showing that the fundamental morphology has remained unchanged for a long time among geo graphically isolated populations within the same species. Thus, carabid evo lution would have proceeded discontinuously, with phases of rapid morpholog ical change alternating with silent phases.