How do ‘The Daleks’ and ‘Genesis of the Daleks’ relate? The history shown in 'The Daleks' contradicts that in 'Genesis', and I want to know the truth about the Kaleds' descendants.
Russell T. Davies suggested some years ago in an episode of Doctor Who Confidential that Genesis of the Daleks could be considered the first strike of the Time War.
Continuity in Doctor Who has always been more of a guideline than a rule; nonetheless, it does appear that it was their encounters with the Time Lords that drove the Daleks to become what they did; in fact, the Time Lords created their own worst enemy.
The origin story at their first appearance, in The Daleks, is not really irreconcilable with the story of Genesis; both agree in broad outline: The Thals and the ancestors of the daleks (called variously Daleks, Dals, or Kaleds) both lived on the planet Skaro (it's unclear whether they were different races of the same species or different species altogether). The Thals and the Dalek ancestors fought a nuclear war; both sides were mutated by the fallout; the Daleks got the worst of it and retreated into metal bodies.
There they would have stayed, if the Doctor hadn't stumbled across them. The Doctor fought the Daleks, and in the process revealed to them the existence of life across the universe. This drove them to leave Skaro and begin attacking the universe around them.
Eventually, the Time Lords became so concerned that they tried to manipulate the history of Skaro to prevent the existence of the Daleks. This is where Genesis comes in.
It's not hard to imagine that the Time Lords launched temporal attacks against the Daleks at multiple points in their time stream, and the Doctor's attack was only the last in a series. If so, it's quite possible that 'earlier' attacks had lengthened the conflict between Thals and Kaleds, or otherwise modified the time stream.
Two things are clear from this. First, that every attempt by the Time Lords to eradicate the Daleks has instead made them stronger, more vicious, more capable. Second, that the Time Lords have been interfering with the Daleks development at multiple points along the time stream. The inconsistency of the Daleks timeline isn't a writing error; it's battle damage.
Like many things over the long run of Doctor Who, the origins of the Daleks are plagued with inconsistencies. There is no way of resolving them, except to throw up your hands and say, "timey-wimey ball." Some expanded universe products considered one origin canonical, and some took the other. The Doctor Who Technical Manual simply stated that there were two stories of the Daleks' origins, leaving the reader to decide which they preferred.
In the Daleks, they decided only to paralyze Ian and did use their weapons to kill. It isn't obvious why the Daleks decided to change colour, but there dependence on static electricity may perhaps be explained as a means to conserve energy? They were entombed and going to be so for a long time. When the Daleks were next met in the Dalek Invasion of Earth, they were given something like dish antennas to explain why they could without static electricity. The next time they appear, The Chase, they were given slats on their sides. The appearance of slats to explain why they could move around was more or less kept for every other story after this. If Doctor Who had been true to the series one might have expected that in Genesis they might have had the dish antenna to move around? However, the use of the dish antenna were probably long forgotten by writers.