They colonise, with their neat bungalows and family businesses, areas of cities (such as South Central in Los Angeles) that both whites and blacks have abandoned.
The research contributes to a more complex picture that has been emerging of humankind during the Late Pleistocene, the period when modern humans left Africa and started to colonise the rest of the world.
Should we be so frivolous by our excessive nature, and be trusted to visit, contaminate and perhaps colonise another planet when we seem so incapable of conserving and looking after our own home world?