Could anyone tell me which skills are required to do a PhD on research. I guess that good communication skills and computer literacy are important. What else?

The skills required depend on the subject you wish to research. In science good laboratory skills can prove almost as important as intellectual ability. In areas of social science you may need to interview large numbers of people and communication skills will be a big factor. In the humanities you may need large amounts of patience to trawl through archive material whilst looking for a needle in a haystack.

Most successful PhD students in any subject are intelligent, persistent and are capable of lateral thinking. You should also be good at surviving on a low income.

intelligence, interest, determination, and sense of humour, and optimism.