Je. Havel et al., Reconstructing the history of intercontinental dispersal in Daphnia lumholtzi by use of genetic markers, LIMN OCEAN, 45(6), 2000, pp. 1414-1419
After its appearance in 1989, the cladoceran Daphnia lumholtzi rapidly disp
ersed throughout the southern United States. In the current study, we used
allozyme and mitochondrial deoxyribonucleic acid sequence data to infer the
past dispersal of this species. Both genetic markers revealed the similari
ty among all U.S. populations and those from Uganda and Nepal but their div
ergence from Australian lineages. The extent of genetic divergence among po
pulations, when coupled with estimates of rates of molecular evolution, sug
gests that the distribution of this species reflects a series of long-dista
nce dispersal events over the last 4 million years.