Does the Darwinian theory require modification or replacement?

By definition. Go for a brief description of Darwin's theory like this: "The origin of species is due to descent with modification from one or several original life forms, a process driven primarily by natural selection."That holds out well now, 152 years after Darwin published OoS, and the papers you're discussing fit it easily. Other processes recognised today like genetic drift create variation, and are encompassed by the word "modification". You can work out for yourself that mutations are largely random, because there are always far more that are detrimental to the organisms than are advantageous. Speeding up mutation in reaction to the environment just means the possibility of getting a random "hit" positive mutation more quickly. It's an initially random tendency in itself that would be selected for if it's advantageous. My name was a joke, but yes it's certainly acceptable to leave out Darwin's name. Scientists names aren't at all important in descriptions of theories.Incidentally, "gene" is a twentieth century word, and mutations on genes is nothing to do with Darwin.Have you decided whether phenotypic plasticity is an indication of magic yet? It's very common, and your link about "root brains" is a good example.When our skin cells react positively to radiation by tanning to protect their DNA, is that an indicator of intelligent design or sapient cells to you? Organisms making positive changes in direct reaction to their environments is something that was observed long before Darwin's time, so it's rather puzzling that you see anything special about the cell reactions described by Shapiro and Wright.

It's certainly advantageous. That might give you a clue as to the entity. Charles and Francis Darwin would have known.I thought it might excite your interest, anyway.