In the programme, we do get a broad sweep of human future history. Some point in the mid third millennium, humans expand across the Milky Way, form colonies and then there are solar flares - and we see the consequences in The Ark in Space and The Beast Below. Humans evacuate Earth, and prepare to return, but in The Sontaran Experiment we see that humans have already returned - these are colonists, for whom Earth is simply where their ancestors came from, in the same way an Australian isn't going to get all that nostalgic about "Mother England" and doesn't see independence from the United Kingdom as a temporary measure.
We then get the interesting Bad Wolf/The Parting of the Ways at the end of Season 27 - a season from which one thing becomes clear. Well two things, which are the flip side of each other. Humans abandon Earth and Earth abandons humanity.
What we see in that story is that by the year 200,100, most humans are living off Earth, and so using the delta wave would only kill the humans still living on Earth. Earth, by that point, had become simply one planet with humans on it.
And earlier that season we have The End of the World - and it seems that humanity are not the only civilisation to come from Earth. After all, Jabe could trace her ancestry back to the Amazon rain forest. In this we are simply a species which existed on Earth for a couple of million years, tops, a blink of an eye in the long story of our planet.
So, what adventures from the classic era would fail the RTD Test?
In Season 1, we have The Daleks, The Edge of Destruction (maybe) and The Keys of Marinus. To misquote the Master from The Five Doctors, a Doctor Who without the Daleks scarcely bears thinking about.
But I am sure if the RTD Test had been in place then, there would be a workaround. Skaro as a human colony planet, with two groups that slowly diverged and ended up at nuclear war with each other? The Thals being human colonists oppressing the native Kaleds (not yet named) who chose to fight back? - well, imagine what the third Doctor would make of that, considering his stories like The Mutants.
The Edge of Destruction - well, I suppose in the RTD Test there is an emphasis on humanity, and this is the one with the Doctor learning that Ian Chesterton and Barbara Wright are useful to have around.
Near the end of Season 1, we have The Sensorites - the first one featuring humans to be based off-Earth and the first one featuring humans to be based in the future. This is actually the seventh story, while these days we are used to new companions having present-day (Rose, Smith & Jones, Partners In Crime, The Eleventh Hour), historical Earth (The Unquiet Dead, The Shakespeare Code, The Fires of Pompeii, Victory of the Daleks), and future humanity (The End of the World, Gridlock, Planet of the Ood, The Beast Below) as their first 3 adventures - interesting to note that both Martha Jones and Donna Noble have their first future adventure as a sequel to one of Rose Tyler's (New Earth and The Impossible Planet/The Satan Pit) respectively. Interesting that by the time we get to Clara Oswald and Season 33, this pattern is broken as Clara's third and fourth adventures - Cold War and Hide - are in the recent past, her sixth (The Crimson Horror) is also in the past, and she has to wait until her seventh adventure (Nightmare in Silver) before travelling to see future humans. The RTD Test is also being broken by this point.
In Season 2, we have The Web Planet (one where the TARDIS crew are the only humanoids) and The Space Museum.
Season 3 gives us Galaxy Four and (potentially) The Celestial Toymaker - although the characters whom Steven Taylor and Dodo Chaplet encounter would be familiar to viewers, including the character who was not based on Billy Bunter. While not one about Earth or humans, it draws from British culture such as clowns, playing cards
and Billy Bunter.
Season 4 is the one where Patrick Troughton takes over as the Doctor, and this is an all-human series. Even ones set off-Earth (Power of the Daleks and The Macra Terror) are human colonists, and Season 5 is the same, with the off-Earth ones being The Tomb of the Cybermen and The Wheel in Space - again, both featuring human explorers or scientists.
Season 6 sees a return to alien races on alien planets, with The Dominators (on Dulkis) and The Krotons (on the Gonds' home planet) being ones where Jamie McCrimmon and Zoe Heriot are the only humans. There is also the weird The Mind Robber, which - like The Celestial Toymaker - is in a fantasy world with figures from British culture.
Seasons 7 to 9 are Jon Pertwee's, with the Doctor exiled to Earth by the Time Lords. Despite this, in Season 8 (Colony in Space) and Season 9 (The Mutants), the Doctor and Jo Grant are sent by the Time Lords to Earth colony planets. Season 9's The Curse of Peladon has a more tenuous link, with Peladon preparing to join the Galactic Federation, and the Doctor being mistaken for the Earth ambassador. Easy mistake to make - after all, sometimes a Spanish ambassador will be mistaken for a Time Lord.
Season 10 sees the Doctor able to travel again. While Carnival of Monsters is not Earth-based, there are humans (namely, those on board the SS Bernice) trapped in the Miniscope. Planet of the Daleks is the first human-free one (apart from Jo) since The Krotons - even The Curse of Peladon had a cameo by the real Earth ambassador - although it does carry on directly from Frontier in Space which covered Earth's dealings with the Draconians.
Season 11 has The Monster of Peladon - although Sarah Jane Smith is the only human, we can put it in the same league as Planet of the Daleks in being a sequel to a Season 10 adventure.
Season 12 brings us to the Tom Baker era, where everything changes again. Genesis of the Daleks fails the RTD Test spectacularly, but it's such a great adventure, we can overlook it.
Season 13 has Planet of Evil, with a Morestran expedition in a story where Sarah is the only human. But it's The Brain of Morbius which introduces a change, with the character of Solon. Up till now, future human stories had been groups - colonists, explorers, scientists. But here is a human with no other humans around him.
Season 14 sees Sarah depart, ending a run of companions from Earth - we will have to wait over 4 years for the next, Tegan Jovanka. And indeed, marking the end of a run of companions, period, as we have The Deadly Assassin, set on Gallifrey and composed of Time Lords (and no Time Ladies).
After that we have the introduction of Leela, the first future human companion since Zoe. Her debut, The Face of Evil, was set on a future planet where the people were descended from an Earth expedition. Some of her adventures - The Robots of Death and Season 15's The Invisible Enemy (in the 51st century, the era of Jack Harkness and River Song, a time where cutting-edge design is robot dogs that are "disco") and The Sunmakers - involve future humans, however in Season 15 there are a couple (Underworld and The Invasion of Time) where she is the sole human.
Season 16 introduces us to Romana, the first non-human companion since Susan Foreman, and Earth and humanity play a smaller part. While The Ribos Operation has a couple of human conpersons, The Pirate Planet, The Androids of Tara and The Armageddon Factor are human-free. Things don't improve in Season 17, with Destiny of the Daleks, The Creature from the Pit and The Horns of Nimon being human-free.
Do things improve in Season 18? Well, The Leisure Hive opens on Brighton beach and did have a handful of humans on Argolis, while Meglos does have a human, we are then into the E-space trilogy of Full Circle (which could have been Earthified (??) by having the people on the Starliner believing they were from Earth originally and then learning they weren't), State of Decay and Warrior's Gate. In State of Decay, the three vampires (including Queen Camilla. Ahem) were originally from Earth. I'm not sure if Rorvik and his crew in Warrior's Gate were human or not, but the following adventure (The Keeper of Traken) is human-free, and the following one, Logopolis, is mainly set on Earth and finally sees a new human companion.
We now move on to Peter Davison's debut in Season 19. Castrovalva begins on Earth, but just ties up loose ends from Logopolis while there. The following, Four To Doomsday, at first glance appears to have humans, but they are androids. However, it is a very human-focussed adventure and deals with a threat to Earth. The rest of the season are all Earth-based, with The Visitation being the first trip to historic Earth since The Talons of Weng-Chiang 5 years earlier.
In Season 20, Arc of Infinity's action is split between Gallifrey and Amsterdam. Snakedance has no humans, other than Tegan, in it, but like Planet of the Daleks and The Monster of Peladon it is a sequel to a story (the previous season's Kinda) which does deal with humanity's future. In Terminus, I think Olvir, Kari and the Lazars are human. Enlightenment sees human sailors in space.
Davison's Season 21 adventures are almost all Earth-based. Frontios is a human colony, and Planet of Fire is one of those - like Logopolis and Castrovalva - where the action begins on Earth before going to another planet.
The final adventure of Season 21 is Colin Baker's debut The Twin Dilemma. Although mainly set on Jaconda, most of the non-Jacondan characters are human.
Now onto Season 22. Attack of the Cybermen follows what must by that stage have been a reasonably familiar pattern - the Doctor encounters something on Earth and that leads to him going to another planet. In Vengeance on Varos, Varos was a human colony. Timelash is primarily set on the non-human world of Karfel, although there is a scene in Victorian Scotland and a human (Herbert). Revelation of the Daleks was set on a human-colonised Necros.
Season 23 goes under the umbrella title of The Trial of a Time Lord. At first, The Mysterious Planet might appear to have nothing to do with humanity, but it emerges that Ravalox is a future Earth.Mindwarp is on Thoros Beta, and like The Brain of Morbius, has a rogue human scientist (Crozier). However, it falls into the same sequel category as Planet of the Daleks, The Monster of Peladon and Snakedance, featuring Sil from Vengeance on Varos.
The Ultimate Foe's action is split between the courtroom and the Matrix.
Now on to Sylvester McCoy's first season, Season 24. Time and the Rani - again a non-human world with non-human characters we cannot relate to. In Paradise Towers, the inhabitants might have been human, and it is possible that in Dragonfire, Iceworld had human customers.
Season 25 has two Earth-based stories - Remembrance of the Daleks and Silver Nemesis. The Happiness Patrol is clearly on a human colony planet and some of the members of the Psychic Circus in The Greatest Show in the Galaxy could have been human.
Season 26 - the end of the classic era - was more simple, with every adventure exclusively or primarily set on Earth.
So, we can identify a number of adventures which would definitely fail the RTD Test:
- The Daleks
- The Keys of Marinus
- The Web Planet
- The Space Museum
- Galaxy Four
- The Dominators
- The Krotons
- Planet of the Daleks
- The Monster of Peladon
- Genesis of the Daleks
- Planet of Evil
- The Deadly Assassin
- The Invasion of Time
- The Pirate Planet
- The Androids of Tara
- The Armageddon Factor
- Destiny of the Daleks
- The Creature from the Pit
- The Horns of Nimon
- Full Circle
- The Keeper of Traken
- The Trial of a Time Lord: Mindwarp
- Time and the Rani
This is where I get controversial. I can think of two points of classic Doctor Who which were low periods. The first was the second half of the Tom Baker era, and the second was the end of the Colin Baker era and the early part of the McCoy era. The first of these is an era with a higher proportion of adventures breaking the RTD Test. What is the programme by that stage? A couple of aliens visiting alien planets populated by aliens and dealing with alien threats. Is it too much to suggest that Doctor Who hits its low points when it forgets - or sidelines - the human aspect?
Consider other TV programmes. Merlin had a consistent universe - set in and around Camelot. There would not be an episode in which a spell of Morgana's sees Arthur on Bowie Base One, wondering what Queen Annis is pointing at him and answering her questions with "Arthur. King. To get back to Camelot." None of the Doctor Who substitutes - Robin Hood, Merlin or Atlantis - have this potential for flitting around in space and time. They are limited to a time and a place.
Unlike these, Doctor Who has the danger of moving away from a human focus.
What about its early sci-fi rival, Star Trek? Now, Doctor Who has a positive view of humanity - described as "indominatible" in The Ark in Space and Utopia - but it isn't starry-eyed. Sorry, but Star Trek came across as having a "White Person's Burden" approach - visit an alien planet, have the events there a metaphor for a contemporary issue, and let the enlighted humans sort it out, because education and science will have made politically incorrect viewpoints an embarrassing thing of the past.
Doctor Who, meanwhile, is more realistic about humanity.
Now, a programme about aliens on an alien planet dealing with aliens could be of interest if a realistic world was created. But in Doctor Who, the Doctor moves on all the time, with no chance for us to understand Chloris or Dulkis. The 3 from Season 16 that have no human connection are at least part of a plot arc - that of the Key To Time. And from Season 17, Destiny of the Daleks can be just about Earthified by the fact that Davros is going to be taken to Earth for trial, so again this is part of a plot arc. But there is no such excuse for The Creature from the Pit or The Horns of Nimon. Now, the later part of the Pertwee era was moving the Doctor away from contemporary Earth-based adventures (normally involving UNIT), and it seems that by the later part of the Baker era this had gone too far.
Now we need to ask whether the RTD Test is still being passed, and this brings us to the Matt Smith era. In Season 32 there is The Doctor's Wife. Not set on Earth - not set in this universe - and the only humans being the companions, Amy Pond and Rory Williams.
Moving on to the most recent season, Season 33, we have Asylum of the Daleks, for which the only human connection apart from the TARDIS crew is the spaceship Alaska. In The Rings of Akhaten, this is a world with no human connections, and it is unclear if the salvage team in Journey to the Centre of the TARDIS were human (they may have been - this is the only Doctor Who recently that I have thought so bad that it's not worth watching to the end).
We shall have to see what direction Season 34 and the Peter Capaldi era takes it in.