Alternate timeline

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An alternate timeline was a reality that diverged from the "true" or "natural timeline" due to the actions of time travellers or other temporal phenomena. They were different from parallel universes in that they did not separate cleanly at the point of creation, resulting in the new timeline destroying the old one. (PROSE: Imperial Moon) The phenomenon may also have been described as an "interstitial spillage of time." (AUDIO: Project: Lazarus)

Physics

Alternate timelines could be visited accidentally by jumping a time track (TV: The Space Museum, AUDIO: The Mutant Phase) or contacting other anomalies (AUDIO: Colditz) in the Time Vortex. Deliberate travel to these timelines was possible if the traveller possessed something, such as the sigil ring, that allowed them to change time streams. (PROSE: Goth Opera)

They may have diverged from points in history when there was temporal fluctuation. The power required to adjust the timeflow and overcome temporal inertia on such a scale couldn't fit on a single planet, but beings with enough power were capable of doing so, such as Sutekh, the Guardians of Time, Rassilon, and the Chronovores. Even the Doctor or the Master could have the know-how or inclination to create them. Because the universe only had a finite amount of mass and energy to exist as one universe, the creation of an alternate timeline or sub-universe adversely affected the real timeline, causing chaos throughout the universe; releasing enough energy could destroy the timeline and set history back on its correct course. The energy released when a TARDIS time rammed another could produce this energy. (PROSE: Blood Heat)

Though a timeline could be negated, memories of it could still be retained. (TV: The Big Bang, The Impossible Astronaut) Sometimes these memories were subconscious and only surfaced in dreams. (AUDIO: The Time of the Daleks, Jubilee) Multiple timelines could co-exist in one continuum; because of this, an individual with multiple futures could come in contact without any Blinovitch Limitation Effects. (AUDIO: Peri and the Piscon Paradox)

Occasionally, time was actually changed so that what was originally the future became an alternate timeline. These were not meant to replace the true timeline but were the result of changes to the real timeline including, apparently, WOTAN conquering Earth (PROSE: The Time Travellers) and the Doctor dying on Grace Alone (AUDIO: The First Wave) and later Trenzalore. (TV: The Name of the Doctor, The Time of the Doctor) This may have related to causality, with knowledge coming before an event rather than an event becoming knowledge. The Doctor encountered WOTAN after it'd conquered Earth in 1966, changing history when he later arrived in 1966; the opposite would be the Doctor arriving in an 1804 where the French Revolution was still happening, as he already knew this was incorrect. (PROSE: The Man in the Velvet Mask)

Two Earth Reptile temporal scientists theorised that after changes were made to history, it took twenty minutes for the new timeline to become established. (PROSE: The Crystal Bucephalus)

Metaphysics

From a metaphysical viewpoint, alternate timelines constantly winked in and out of existence with every decision made, (AUDIO: The Wrong Doctors) always being extinguished as fewer and fewer choices became open. This was particularly affected by time travellers who changed the future whenever they arrived in a new time. This was the cosmic pain of the universe and in this manner Gabriel and Tanith were personifications of the timelines that never existed. (PROSE: Falls the Shadow)

The existence/creation of alternate timelines and parallel universes was held in check by the existence of the Time Vortex, which was sustained by the existence of the Time Lords who created it. (PROSE: The Domino Effect)

Terminology

The phrase "alternate/alternative timeline/universe/reality" was sometimes used interchangeably with "parallel universe"; however, alternate timelines usually changed after a single moment in time, whereas parallel universes usually had more than one difference from the "normal" universe.

Timelines

Timelines encountered by the Doctor

Timeline Negated By Featured in
The TARDIS crash lands on a planet in a state of temporal flux, leading to Susan Foreman surviving alone via a Zero Cabinet, while everyone else dies. Susan Foreman and Alternate Susan, via the Blinovitch Limitation Effect AUDIO: Tick-Tock World
The First Doctor and his companions became exhibits in the Moroks' Space Museum First Doctor, Ian Chesterton, Barbara Wright, and Vicki TV: The Space Museum
Barbara Wright married Ptolemy I and became Queen of Alexandria Alternate Barbara PROSE: The Book of Shadows
The Monk switched the First Doctor with the Fifth Doctor, resulting in the Fifth Doctor making a decision different from his former self, and allowing the Monk to hijack his timeline Fifth Doctor and Sophia, by forcing the Monk into a situation with his only way out being to give the Doctor back his timeline AUDIO: The Secret History
Christopher's death causes his father to leave and his mother to commit suicide, leaving his twin brother Robert alone until he finds a time machine and begins travelling. The First Doctor, Steven Taylor, Sara Kingdom, and Robert PROSE/AUDIO: The Little Drummer Boy
The First Doctor, Steven Taylor, and Oliver Harper died on Grace Alone Oliver Harper AUDIO: The First Wave
1794 Earth became the World Machine, with the French Revolution continuing until 1804 The Pageant after being confronted by the First Doctor PROSE: The Man in the Velvet Mask
WOTAN conquered Earth (this was the correct timeline before it was changed by the Doctor) First Doctor PROSE: The Time Travellers, TV: The War Machines
Mechanistria was taken over by machines possibly negated by Drako, though he might not have succeeded PROSE: Peril in Mechanistria
The Second Doctor's TARDIS collided with the First Doctor's TARDIS, diverting the earlier TARDIS from landing on Kembel, meaning the First Doctor never stopped the Daleks from developing the Time Destructor Second Doctor and Katarina AUDIO: Daughter of the Gods
The Monk switched the Second Doctor with the Sixth Doctor, so that the Sixth Doctor would make a different choice than his former self did originally, allowing the Monk to hijack the Doctor's timeline Sixth Doctor and Zoe Heriot, by creating a time loop that ensures the end of the Great Cyber War occurs when it's supposed to AUDIO: Last of the Cybermen
Nancy Grover used Grold technology to become a goddess Third Doctor and Liz Shaw PROSE: The Eye of the Giant
The Power Elite took over Earth Third Doctor PROSE: Prisoners of the Sun
Freedom fighters from the 22nd century assassinated Sir Reginald Styles, causing a war which enabled the Daleks to invade Earth Third Doctor and Jo Grant TV: Day of the Daleks
The Monk switched the Third Doctor with the Seventh Doctor, so that the Seventh Doctor would make a different choice than his former self did originally, allowing the Monk to hijack the Doctor's timeline Jo Grant, by preventing the Seventh Doctor from sacrificing the TARDIS to save the Europans AUDIO: The Defectors
Theodore Cassells's experiments led to a global war which devastated Earth Third Doctor COMIC: A Stitch in Time
The Third Doctor regenerated on Dust and became infected by Faction Paradox's virus in the process Eighth Doctor by destroying Gallifrey (PROSE: The Gallifrey Chronicles) PROSE: Interference - Book One, Interference - Book Two
Sutekh was freed in 1911 and devastated Earth Fourth Doctor and Sarah Jane Smith TV: Pyramids of Mars
In the year 4000, Jalnik uses a crack in time to pull the Pantophagen out of the time Vortex, Earth is devastated by them. Fourth Doctor AUDIO: The Foe from the Future
A Bellascon scientist bombed the Terradonian Starliner, erasing Adric from existence Narvin AUDIO: Erasure
The existence of the planet Bellascon (this was the correct timeline until Narvin used the Oubliette of Eternity) Narvin AUDIO: Erasure
Gallifrey is destroyed in the ancient past by the Machine, full of active fusion bombs, arriving on the planet, resulting in the Ferutu evolving to become the Lords of Time Fifth Doctor, Seventh Doctor, and the Ferutu PROSE: Cold Fusion
Daleks underwent the Mutant Phase Dalek Emperor AUDIO: The Mutant Phase
John Smith and the Common Men were the most successful band in the world instead of the Beatles Fifth Doctor and Nyssa AUDIO: 1963: Fanfare for the Common Men
Melanicus created the Millennium Wars Fifth Doctor, Sir Justin, and Shayde COMIC: The Tides of Time
The 22nd century Dalek invasion didn't take place Fifth Doctor and Nyssa AUDIO: Renaissance of the Daleks
Earth in 2008 was controlled by smoke creatures Fifth Doctor, Nyssa, and Thomas Brewster AUDIO: The Haunting of Thomas Brewster
Adric created a city of intelligent scorpions Fifth Doctor and Nyssa AUDIO: The Boy That Time Forgot
Phil and Trev created a perfect world Fifth Doctor, Nyssa, and Thomas Brewster AUDIO: A Perfect World
Stockbridge had an Eternal Summer Fifth Doctor, Nyssa, and Maxwell Edison AUDIO: The Eternal Summer
Mike Bretherton investigated the missing people abducted by the Hexagora Fifth Doctor AUDIO: Hexagora
In his fifth incarnation, the Doctor is killed prematurely by Brooke 1, causing stars to burn out across the universe. Brooke, by convincing Andrew Edwardson to take the Doctor's place, giving his own life to save his doppelganger. AUDIO: My Dinner with Andrew, The Furies
The Herd-Leader of the Bovine travelled back in time to warn himself he shouldn't help Columbus discover America Peri Brown and Christopher Columbus AUDIO: Trouble in Paradise
Walter Raleigh went back in time and encountered aliens Sixth Doctor AUDIO: Voyage to the New World
The Doctor's arrival on the planet Bixor to investigate the cause of its destruction, turned out to be the actual cause of its destruction Sixth Doctor AUDIO: The Wings of a Butterfly
Cyberverse Possibly negated when Evelyn Smythe left the Sixth Doctor WC: Real Time/AUDIO: Real Time
Daleks invaded Earth in 1903 and were defeated by the British Empire the last surviving Dalek AUDIO: Jubilee
Wolfgang Amadeus Mozart became immortal Sixth Doctor and Evelyn Smythe AUDIO: My Own Private Wolfgang
Thomas Caxton fell through a tear in time, ending up in 1913. He then made multiple changes to the timeline in an attempt to prevent World War I. Sixth Doctor AUDIO: Fortunes of War
The Valeyard used the Nathemus to steal the Sixth Doctor's life, and eventually, the lives of every Time Lord to ever exist. Sixth Doctor AUDIO: The Brink of Death
President Bailey allowed the Slithergee race to settle on the first moon of the planet Puxatornee in the year 3060, which allowed the Slithergee to take complete control of the planet in the year 3090 Seventh Doctor, Mel, Stuart, and Reed AUDIO: Flip-Flop
The assassination of President Bailey caused the next President, Mitchell, to declare war on the Slithergee race in the year 3060, the result of which left the planet Puxatornee devastated by the year 3090 Seventh Doctor, Mel, Lieutenant Stuart, and Lieutenant Reed AUDIO: Flip-Flop
Alternate timeline (The Ripple Effect) Seventh Doctor PROSE: The Ripple Effect
Humans evolved into Haemovores Seventh Doctor and Ace TV: The Curse of Fenric
The Dark Matrix terrorised England Seventh Doctor and Ace PROSE: Matrix
The Nazis won World War II after a piece of laser technology was left at Colditz Castle Alternate Eighth Doctor and Elizabeth Klein (inadvertently) AUDIO: Colditz, Klein's Story
Vladimir Kryuchkov succeeded Konstantin Chernenko as leader of the Soviet Union, causing World War III to occur in 1989 Seventh Doctor AUDIO: Protect and Survive
Adolf Hitler used the Timewyrm's power to enable Nazi Germany to conquer Earth Seventh Doctor and Ace PROSE: Timewyrm: Exodus
Chad Boyle killed Dorothy McShane with a brick to the head Ace PROSE: Timewyrm: Revelation
The Process came into being and enslaved the Time Scaphe crew Seventh Doctor and Vael PROSE: Cat's Cradle: Time's Crucible
Silurian Earth Destroyed, not negated, by Seventh Doctor PROSE: Blood Heat
The Garvond never came into being Artemis the Chronovore PROSE: The Dimension Riders
Huitzilin died without becoming a psychevore Artemis the Chronovore PROSE: The Left-Handed Hummingbird
The Land of Fiction remained inactive Artemis the Chronovore PROSE: Conundrum
Brigadier Lethbridge-Stewart was shot and killed by a Vardan in 1976 Artemis the Chronovore PROSE: No Future
Alternate timeline (Time & Time Again) Seventh Doctor, Ace, and Bernice Summerfield COMIC: Time & Time Again
The Knights of Velyshaa conquered Gallifrey Fifth Doctor, Sixth Doctor, Seventh Doctor, and the Temperon AUDIO: The Sirens of Time
Elizabeth Klein created the Galactic Reich after stealing the Doctor's TARDIS and making repeated corrections to the timeline Seventh Doctor, Elizabeth Klein, and the Selachians (the last two inadvertently, after being manipulated by the Doctor) AUDIO: The Architects of History
Edward Grainger wrote My Life With The Doctor Seventh Doctor PROSE: Testament
The Saturnius collided with the TARDIS River Song AUDIO: The Unknown
Earth was destroyed by the Eye of Harmony Eighth Doctor and Grace Holloway TV: Doctor Who
Sato Katsura formed the Church of the Glorious Dead which conquered Earth Kroton COMIC: The Glorious Dead
Humans didn't evolve and Earth was a Tractis colony known as Paratractis Eighth Doctor, Sam Jones, and Jo Grant PROSE: Genocide
Edward Grove came to life Eighth Doctor and Charley Pollard AUDIO: The Chimes of Midnight
Sebastian Grayle became immortal and helped the Nimon conquer Earth Eighth Doctor and Charley Pollard AUDIO: Seasons of Fear
Shakespeare vanished from history Eighth Doctor and Charley Pollard AUDIO: Invaders from Mars, AUDIO: The Time of the Daleks
Daleks invaded Earth in the 17th century Eighth Doctor and Charley Pollard AUDIO: The Time of the Daleks
The Master used a conceptual bomb made from Bob Dovie's refusal to accept the existence of the Doctor's TARDIS to erase said TARDIS, thus meaning the Doctor never left Gallifrey First Doctor, Second Doctor, Third Doctor, Fourth Doctor, Fifth Doctor, Sixth Doctor, Seventh Doctor, and Eighth Doctor AUDIO: The Light at the End
Morbius returned and defeated the Time Lords Eighth Doctor, Time Lords AUDIO: The Vengeance of Morbius
Straxus became Kotris and saved the Dalek Time Controller Dalek Time Controller AUDIO: The Great War, Fugitives, Tangled Web, X and the Daleks
After living with the stranded Eighth Doctor at 107 Baker Street, Robin Bright-Thompson joined Divine Intervention and led it in establishing a Human Empire, eventually resulting in humanity's extinction The Curator AUDIO: Stranded
107 Baker Street was destroyed during World War II Liv Chenka, Helen Sinclair, Andy Davidson and Tania Bell AUDIO: The Keys of Baker Street
The Daleks carried out a series of assassinations using a temporal eradicator to reverse the couse of recent defeats in the Time War. War Doctor AUDIO: The Shadow Squad
The Barber-Surgeon waged a campaign in the Time War, during which he killed the Master after he was sent to assassinate him and the Dalek Emperor had the Dalek Time Strategist executed. Barber-Surgeon AUDIO: The Mission, The Abyss, The Horror
Having broken through the quantum shield erected to protect Earth during the Time War, the Daleks arrived in East Berlin in 1961 and proceeded to exterminate humanity. Overruled but not negated by the War Doctor AUDIO: The Shadow Vortex
The Eternity Circle created the Temporal Cannon and Temporal Weapon Daleks and controlled the Tantalus Spiral. War Doctor and Borusa PROSE: Engines of War
The Ravagers were released from containment. Ninth Doctor AUDIO: Sphere of Freedom, Cataclysm, Food Fight
Pete Tyler didn't die and Reapers began consuming humanity Pete Tyler TV: Father's Day
Giovanni Lucio helped Massimo conquer the Roman Empire Tenth Doctor and Rose Tyler COMIC: The Futurists
The Year That Never Was Tenth Doctor, Martha Jones, and Captain Jack Harkness TV: Last of the Time Lords, PROSE: The Story of Martha, AUDIO: The Year of Martha Jones
The Pyroviles conquer Earth Tenth Doctor and Donna Noble TV: The Fires of Pompeii
The entire crew of Bowie Base One died on Mars on November 21, 2059 (this was the correct timeline before it was changed by the Doctor) Tenth Doctor TV: The Waters of Mars
The Kotturuh continued to exist into the Doctor's era (this was the correct timeline before it was changed by the Doctor) Tenth Doctor AUDIO: Lesser Evils
Gabby Gonzalez evolved into the Vortex Butterfly, resulting in the Tenth Doctor leaving her in an empty gulf of space Tenth Doctor, Twelfth Doctor, and Vortex Butterfly COMIC: Vortex Butterflies
The Tenth Doctor and Anya Kingdom arrived in the Lost's dimension. Tenth Doctor AUDIO: The Lost
The Tenth Doctor chose to let Wilfred Mott die in the Naismith mansion, eventually becoming the Time Lord Victorious and taking over the universe Tenth Doctor, Eleventh Doctor, Twelfth Doctor, Gabby Gonzalez, Alice Obiefune, and Clara Oswald COMIC: Four Doctors
The Progenitor Daleks repopulated Skaro and exterminated humanity to extinction in 1963 Eleventh Doctor and Amy Pond GAME: City of the Daleks
The Kin gained control of Earth meaning humanity was extinct in 2010 Eleventh Doctor PROSE: Nothing O'Clock
Vincent Van Gogh paints the Krafayis into one of his works Eleventh Doctor and Amy Pond TV: Vincent and the Doctor
The Starless world Eleventh Doctor, Amy Pond, Rory Williams (Auton), and River Song TV: The Big Bang
Kazran Sardick was a heartless and cruel old man Eleventh Doctor and a young Kazran Sardick TV: A Christmas Carol
Ship kidnapped people and wiped Foxtown off the map Eleventh Doctor PROSE: The Way Through the Woods
Amy Pond was stranded on Apalapucia for 36 years Eleventh Doctor, Rory Williams, Amy Pond, Alternate Amy Pond TV: The Girl Who Waited
River Song's World Eleventh Doctor, Amy Pond, Rory Williams, River Song, and the Teselecta TV: The Wedding of River Song
The Eleventh Doctor chose not to undo River Song's World, living out his life with River Song while the universe dies Tenth Doctor, Eleventh Doctor, Twelfth Doctor, Gabby Gonzalez, Alice Obiefune, and Clara Oswald COMIC: Four Doctors
The Silurians attempted to pump poison onto Earth's surface to reclaim it Eleventh Doctor and River Song GAME: The Eternity Clock
The Progenitor Daleks invaded and destroyed London in or before 2106 Eleventh Doctor and River Song GAME: The Eternity Clock
Amy Pond was killed by Jack the Ripper Eleventh Doctor COMIC: Ripper's Curse
The Cybermen conquered the galaxy Eleventh Doctor and Jean-Luc Picard COMIC: Assimilation²
Rory Williams remained imprisoned in Winter Quay for the rest of his life Rory Williams and Amy Pond TV: The Angels Take Manhattan
Penelope became the Paradox and killed the people who had wronged her. Eleventh Doctor and Penelope AUDIO: The Art of Death
The Creevix erased the existence of Guy Taylor, allowing them to use his time machine to enter the universe on 23 November 2013 and consume it First Doctor, Susan Foreman, Second Doctor, Jamie McCrimmon, Zoe Heriot, Third Doctor, Mike Yates, Fourth Doctor, Romana II, Fifth Doctor, Adric, Nyssa, Tegan Jovanka, Sixth Doctor, Peri Brown, Seventh Doctor, Ace, Eighth Doctor, Charley Pollard, Ninth Doctor, Rose Tyler, Jack Harkness, Tenth Doctor, Donna Noble, Eleventh Doctor, Alice Watson, and Cedric Chivers AUDIO: The Time Machine
The TARDIS was damaged by van Baalen Bros. and self-destructed Eleventh Doctor TV: Journey to the Centre of the TARDIS
The Great Intelligence negated the Doctor's victories Clara Oswald TV: The Name of the Doctor
The Doctor died on Trenzalore and the planet became a battlefield graveyard (this may have been the correct timeline before it was changed) Clara Oswald, the Time Lords and the Eleventh Doctor TV: The Time of the Doctor
The memories of Clara Oswald and the Tenth, Eleventh, and Twelfth Doctors were rewritten to ensure the existence of an alternate Twelfth Doctor, while Alice Obiefune was killed by Voord guards Eleventh Doctor and Alice Obiefune, by planting a Weeping Angel that transported Gabby Gonzalez back in time COMIC: Four Doctors
The Twelfth Doctor didn't forgive Clara Oswald for betraying him, leading him to become the leader of the Voord Tenth Doctor, Eleventh Doctor, Twelfth Doctor, Gabby Gonzalez, Alice Obiefune, and Clara Oswald COMIC: Four Doctors
The Cybermen allied with Rassilon and started to alter history and harvest regenerative energy from Time Lords to use it in the creation of a new Universe Twelfth Doctor, Rassilon COMIC: Supremacy of the Cybermen
The Raoultella planticola bacteria wiped out all life on Earth by 2018 Twelfth Doctor TV The Pyramid at the End of the World
Captain Archibald Hamish Lethbridge-Stewart and a German soldier killed each other on December 25, 1914 (this was the correct timeline before it was changed by the Doctor) Twelfth Doctor TV: Twice Upon a Time
Sea Devil Earth Skithra Queen COMIC: A Little Help from My Friends, Alternating Current
The Sontarans invaded Liverpool, then travelled back to invade Russia, and fight in the Crimean War. Dan Lewis, Karvanista TV: War of the Sontarans

Timelines encountered by others

Timeline Negated By Featured in
Peri Brown was not assassinated and lived with King Yrcanos as a Warrior Queen Not negated but existing due to a Time Lord faction AUDIO: Peri and the Piscon Paradox
Peri Brown did not live with Yrcanos and was returned to Earth with her memories of the Doctor erased save for her first adventure with him Not negated but existing due to a Time Lord faction AUDIO: Peri and the Piscon Paradox
Peri Brown's future was altered another three times Not negated but existing due to a Time Lord faction AUDIO: Peri and the Piscon Paradox
The Seventh Doctor defeated the Vardan invasion of Earth by leaving clues for his past self The Monk PROSE: No Future
Insects of the Mind evolved as the dominant life on Earth The existence of time travel PROSE: Falls the Shadow
Britain was a conformist republic The existence of time travel PROSE: Falls the Shadow
Antonin's timeline Not negated but existing within the Axis AUDIO: Reborn
Burner Doctor's timeline Not negated but existing within the Axis AUDIO: Disassembled
True Lords' timeline Not negated but existing within the Axis AUDIO: Annihilation
Regenerators' timeline Not negated but existing within the Axis AUDIO: Forever, Emancipation, Evolution, Arbitration, Extermination
Romana's second incarnation regenerated on the Moros and Omega escaped the anti-matter universe during the ensuing presidency of her third incarnation Irving Braxiatel AUDIO: Intervention Earth, Enemy Lines
The Watchmaker killed Narvin and Ace Romana, Leela and the Watchmaker AUDIO: Enemy Lines
Torchwood and Divine Intervention failed to prevent a devastating war beginning in Hull involving humanoid wolves and androids Mr Bird AUDIO: Get Andy
The War Master used the Anti-Genesis codes to replace Davros as the Daleks’ creator, creating his own race of Daleks who conquered the universe The Master, another version of the Master from a parallel universe and the Dalek Time Strategist AUDIO: Anti-Genesis
Leela was killed in an alien attack on Gallifrey, prompting President Romana to order the destruction of the Cannavar system in retaliation Not negated but existing within the Beyond AUDIO: Beyond
The Dark took over members of Torchwood Torchwood and Bilis Manger PROSE: The Twilight Streets
Andrea Yates' World alternate Andrea Yates TV: Whatever Happened to Sarah Jane?
The Trickster's World Eddie and Barbara Smith TV: The Temptation of Sarah Jane Smith
Donna's World alternate Donna Noble TV: Turn Left
The stars go out in Pete's World as the walls of reality broke down DoctorDonna TV: Journey's End
Ship erased Sarah Jane Smith, Luke Smith and Clyde Langer Adam Lloyd and Rani Chandra TV: The Mad Woman in the Attic
Taphony rapidly ages Alistair Gryffen while draining Jorjie Turner of her energy. Taphony, by departing through the vortex of the Space-Time Manipulator, reversing time by a day and resulting in everyone forgeting her bar K9 Mark 2. TV: Taphony and the Time Loop
Ben and Katy die in a fire Sarah Jane Smith and Emily Morris TV: Lost in Time
Deindum from the future conquered the galaxy Bernice Summerfield PROSE: Present Danger, AUDIO: Escaping the Future
Use of GENIEs cause devastation to the Earth A GENIE and those who commanded it PROSE: The Stone Rose
Simon Brown's public release of information regarding the atomic bomb causing Joseph Stalin to use his atomic bombs on the Earth to maintain control. Honoré Lechasseur and Emily Blandish travelling back to 1949 to stop events from occurring. PROSE: The Winning Side
John Hart meets Queen Victoria in 1887, marries her and ultimately becomes King of the British Empire. Jack Harkness, by dying despite being a fixed point in time, causing John Hart's version of reality to collapse. AUDIO: The Death of Captain Jack
The universe is consumed and left dead by the Master's ultimate form which exists as pure hunger Missy being consumed by her future self, resulting in a paradox. AUDIO: Masterful

Species from alternate timelines

Some species existed entirely as a result of diverges in time, including the Haemovores, a result of Fenric poisoning humanity; (TV: The Curse of Fenric) the Mind, before being destroyed by Gabriel and Tanith; (PROSE: Falls the Shadow) the Daleks affected by the Mutant Phase - an evolution of Daleks; (AUDIO: The Mutant Phase) and the Skaro Degradations, Dalek permutations from other timelines. (PROSE: Engines of War)

Behind the scenes

Terminology

The phrase "alternate timeline" is used in The Ancestor Cell, Beige Planet Mars, The Eye of the Giant, Just War, Legacy, Mad Dogs and Englishmen and The Shadow of Weng-Chiang. The phrase "alternative timeline" is used in Blood Heat, The Blue Angel, Cold Fusion, The Eight Doctors, The Eyeless, Imperial Moon, The Ripple Effect, Spiral Scratch and The Temptation of Sarah Jane Smith.