Literature: Dragonriders Of Pern aka: Dragon Riders Of Pern
Pern, an isolated world with no useful resources, seemed like the ideal place for people tired of technology to establish a pastoral utopia, until Thread started falling from the skies. An alien fungus that could devour a cow in seconds had not been part of the plan. Rather than permanently resort to technological measures, the colonists used genetic engineering to create dragons, a solution compatible with their principles since, like the spaceships that had brought them to Pern, it was technology they could use once, then discard. Using planes to fight Thread would meant living in an industrial society capable of supporting them; dragons could be supported by the idealised medieval society the settlers had wanted. There's also the matter that they'd been warned the planet's resources were "negligible" - there's insufficient metal and fuel for such an industrial society, wanted or not.The first Pern story, Weyr Search, was published in 1967. Anne McCaffrey kept writing them for another forty years, though later in collaboration with her son.Most of the books take place over two thousand years after Pern was first settled, beginning when Thread has been absent for 400 years, ever since most of the dragon riders mysteriously disappeared. Only a handful of people still believe Thread was ever real, and there aren't enough dragons left to fight it if it should return, which it is due to do any day now. Fortunately, it turns out that dragons aren't just fire-breathing telepathic teleporters; they can also Time Travel. The heroine travels 400 years into the past, and brings forward the missing dragon riders, creating a Stable Time Loop.Subsequent books dealt with the culture clash between the old-fashioned time-displaced dragon riders and the people they had come to save, and with the gradual rediscovery of technology, which led to the unearthing of the original spaceship, and a final end to Thread. There are also several prequels, describing how various aspects of Pern society came to be. Some of the books overlap with each other, covering the same events but following different characters.The first books had a Fantasy feel, with a few Science Fiction trappings, but later books have moved into Fantasy That Wants to Be Science Fiction territory.There was also a board game from Nova Game Designs.
These books provide examples of:
Abusive Parents: Petiron was not a good father, to put it lightly. Not actively vicious, but cold and harshly critical of Robinton to the point where it's hard to tell the difference. Then there's Menolly's father beating her for composing music, and her mother deliberately attempting to cripple her hand so she can't play an instrument. She rises above every other hardship in her life, but she never forgives her parents.
Jaxom grew up as the ward of Lord Warder Lytol, an ex-dragonrider. While Lytol was by no means abusive, suffice to say that growing up with an Empty Shell for a father substitute did not make life easy for Jaxom.
Ace Pilot: McCaffrey based her dragon riders' personalities and physical characteristics on real-life fighter pilots.
Action Girl: Female dragonriders in general — Moreta, Sorka, and Mirrim, in particular.
Agony of the Feet: Menolly gets caught out during Threadfall and runs the skin off the bottoms of her feet (after wearing through the soles of her shoes) trying to reach shelter. She's spotted and rescued by a dragon and rider. Years later, she comments that her feet are still unusually sensitive.
A.I. Is a Crapshoot: Averted with AIVAS, who is basically an anti-HAL. Not only does he help free Pern from thread forever, he commits suicide afterwards so that the people of Pern won't become dependent on him.
Alien Blood: Pernese native animals have green, copper-based blood.
Alien Sky: The Red Star, of course, but Pern also has two moons. Plus, Pern is far enough away from Earth that the night sky would look very different, with none of the familiar constellations. A few references in The Skies of Pern do make it clear that at least some of the same stars are visible, though naturally from a completely different perspective.
Dragon mating has a profound psychic effect on nearby humans, particularly their bondmates, making a sexual union between their riders near-compulsory. Weyr culture has adapted to this situation, so permanent relationships among dragonriders are rare. However, a rider's preference can influence his/her dragon's choice of partner — witness the fact that Mnementh and Ramoth always mate despite the competition from dozens of other bronzes.
It's noted in Dragonseye that the riders don't necessarily pair off as the dragons do, but all that needs to happen is that the rider stays near their preferred partner during a mating flight. One character in the book notes that "there are plenty of people interested" in participating when a mating flight is in progress.
Fire lizards have a similar effect on their humans, although not as compelling. Still, if you own a gold and someone near you owns the only bronzes in the vicinity, and she decides to have a mating flight...you'd better like each other pretty well. In several cases, such as Menolly and Sebell, this leads to a Relationship Upgrade.
Alphabetical Theme Naming: Dragons name themselves at Impression, always with a name that ends in -th: Faranth, Ruth, Mnementh, etc. Why they all seem to hatch instinctively knowing to do this is not explained or even brought up.
Aristocrats Are Evil: The lion's share of the Lord Holders at the beginning of the series are spiteful, narrow-minded old men that create headaches for F'lar and the other protagonists on a regular basis. They gradually get replaced by younger and more reasonable successors.
Author Catchphrase: McCaffrey has a name, "Johnny Greene", or "J.G.", that she likes to insert into most of her works. Jayge is an example.
Bad Moon Rising: Well, technically it's a planet, but the Red Star definitely counts.
Best Served Cold: Lessa was ready to wait ten years disguised as a menial servant to take revenge on the man who slew her entire family. During this time she turned Ruatha, one of the wealthiest Holds, into a complete ruin through simple sabotage and slight telepathic emotional adjustments, and manipulated F’lar into a duel with Fax to make him pay. She was only ten years old when this started.
Blind Jump: Going between without a destination firmly in mind will cause the dragon and its passenger(s) to never emerge, which is fatal. Poorly imagining one's destination can result in a Tele Frag. Conversely, imagining aspects of one's destination too well can result in accidental Time Travel. This is all covered in the extensive training given to young dragonriders, with the grisly examples of those who didn't pay attention in the past serving to drive the lessons home.
Bond Creatures: Both dragons and fire lizards, since the former are descended from the latter.
A Boy and His X: Dragonriders and their dragons; at various points, people in general and their fire lizards.
Breath Weapon: Most of the dragons ingest an ore called "firestone" to enable them to breathe fire. The phosphorus in the firestone reacts with the dragon's stomach acid to produce phosphine (chemical formula PH3), a poison gas that ignites spontaneously upon contact with air. The egg-laying gold dragons aren't allowed to chew firestone because it has the side effect of sterilizing females. In Dragonsdawn, queens who try to eat firestone vomit it back up, making it necessary for their riders to use flamethrowers.
Bring My Brown Pants: Discussed by riders in Dragonseye who are about to face the first Threadfall in two hundred years.
Lessa. She was the only survivor of a slaughter that killed the rest of her family and then spent years hiding who she was as a lowly servant. She gets better.
Menolly's only friend and who would encourage her abilities died and then her father put her through a great amount of abuse to ensure she never sang or played again. Her mother helped him do it.
The Bully: Piemur faced a quartet of them in the Drum Heights, and the abusive Journeyman Dirzan who ignored his complaints about the four bullies. The bullies' last act against him was to grease the steps of the stairs, so he would slip on his run back up the steps.
Call a Rabbit a "Smeerp": Runnerbeasts and herdbeasts, sort of. While they are related to horses and oxen (and are described as looking similar), they were significantly genetically engineered by the original colonists, so they're probably a different species, technically.
Can't Live Without You: Once a rider dies, the dragon normally commits suicide post-haste. Moreta's queen is temporarily tethered by her mothering instinct for the eggs she just laid, but suicides as soon as they hatch. Riders whose dragons die also frequently suicide; those who don't, such as Lytol, remain somewhat shattered for the rest of their lives, if not outright mindblasted (Kylara). Brekke is helped a great deal by her rare ability to hear other dragons.
Menolly is accepted by almost everybody in Harper Hall...but the ones who object to her presence make her life hell. A rare example of the protagonist not winning everyone over; instead, she settles for getting her own back.
Piemur's example is worse: after his voice breaks, he's sent to become a drum apprentice until his voice stabilizes. However, he's also made Master Robinton's apprentice, which often involves being sent on very confidential missions. Determined to prove that he's not just a joker and a slacker who coasts by on natural talent, Piemur makes a decision to stop playing around and start working — and the other drum apprentices, who were expecting the joker, don't take it well, especially when Piemur learns drum measures at a speed most of them probably couldn't match. His going on said missions, including one to a Gather at Igen Hold and, as far as they knew got a free day because of a Hatching at Benden Weyr*
In truth, he went the Hatching but knew that would make things worse.
, just makes it a lot worse*
Starting with finding his belongings and bed soiled with urine upon his return and ending with them greasing some steps so he nearly killed himself returning up the steps.
. Further problematic was the Journeyman who was generally on watch never believed him on any matters.Then Menolly, by then a Journeyman herself, and Master Robinton, found out what was going on and the shit hit the fan very hard indeed.
Dragons' colors denote gender, size, and rank, exactly as their fire lizard ancestors. Gold = Queens, the dominant females and the primary egglayers; Bronze = the largest and dominant males, ridden by wingleaders; Brown = smaller and weaker males, tend to be ridden by wingseconds; Blue = the smallest, fastest, and least intelligent males; Green = the smallest, subordinate females, who are typically infertile due to firestone consumption.
The various Holds and Crafts have traditional colors and shoulder knot patterns that denote rank and affiliation. About the only color ever consistently mentioned is that Harpers are associated with a light shade of blue known as "Harper Blue."
Comet of Doom: The Red Star, although it's technically not a comet, serves the role plot-wise. There's a more direct example in The Skies of Pern.
Conflict Ball: Some characters seem to switch between supportive and antagonistic between books as plot demands.
Jayge and Aramina, who were seeking confirmation of dolphin intelligence from AIVAS in All the Weyrs so their son and his friends wouldn't be seen as crazy, to Dolphins where they thought he was crazy and irresponsible.
Toric is a force unto his own, see Wild Card below.
Corrupt Bureaucrat: Chalkin, Lord Holder of Bitra in Dragonseye, who refuses to believe that Thread will return and won't take the necessary precautions to protect his people. And that's just the tip of the iceberg of the things he does.
Culture Clash: Between Weyr, Hold, and Craft. Their traditions have diverged sharply over the centuries and frequently come into conflict in the main storyline. Similarly, a major conflict arises between the Oldtimer Weyrfolk who are brought forward in time by Lessa and the more "modern" Weyrfolk under F'lar's command.
Death by Childbirth: Happens to Jaxom's mother, and is generally a risk in a low-tech, feudal society.
Death World: F'nor and Canth pay a visit to the Red Star and come back near-dead and skinless from the corrosive, unbreatheable atmosphere.
Despair Event Horizon: The death of a dragon or its rider will send the living member of the pair into despair or insanity. If the rider dies, his dragon will invariably commit suicide by going between. If the dragon dies, the rider may become Ax Crazy, suicidal, an Empty Shell, or all of the above.
Didn't Think This Through: Tenim's plan towards the second half of Dragon Fire is to amass a vast amount of firestone before Thread returns and then destroy the source so that he can profit from controlling its supply to the dragonriders. Tenim seems to miss the obvious flaw with this plan; since dragonriders go through a lot of firestone over a short period of time, his supply wouldn't last very long, and if it ran out when Thread started falling practically everyone on the planet would die.
Disappointed In You: Piemur wanted to prove himself to Robinton and Menolly. He didn't want to disappoint them. So he kept silent about the full extent of the abuse his fellow drum trainers were putting him through. Even after he nearly died because they greased the stairs, this was the reason he gave. His friends were horrified at the thought that they inadvertently caused the situation by putting the pressure on him.
Domestic Abuse: F'lar is very rough with Lessa at first; he gets less so as their relationship matures.
Drowning My Sorrows: Even decades later, Lytol drinks to unconsciousness after a dragon dies to numb the pain of losing his.
Robinton is also overly fond of drink, and has been ever since his bride Kasia drowned on their honeymoon. Though he's managed to cultivate a reputation as a wine connoisseur, and so his frequent drinking is rarely looked down upon.
Due to the Dead: Centuries after she sacrificed her life to save Pern, Sallah Telgar's body is brought down from space and given a very elaborate ceremonial funeral, including the coffin being borne by queen dragons.
Menolly is first introduced in Dragonsong as singing the funeral elegy for Petiron.
Empty Shell: If a rider who loses his dragon does not commit suicide, he or she is frequently left as this. The quintessential example is Kylara, who is left almost catatonic when her queen dies.
Lytol manages to avert this. While he never gets over the pain of losing his dragon, he presses on through life by engaging in other pursuits. First by being a Weaver, then by dedicating himself to making Ruatha Hold prosperous again for his ward Jaxom, whom he treats as a son.
Enemy to All Living Things: Thread eats its way through anything organic — being tied out during threadfall is the single most dire punishment that a criminal can be sentenced to. Drowned Thread OTOH (Thread can't survive in water) is a rich food source for marine life. While the rest of Pern suffers due to Thread, fish and other sea animals thrive.
Eternal English: Over 2500 years on Pern have introduced a lingual shift despite the best efforts of the Harpers. However, the shift is not so severe that, allowing for the loss of context, they cannot understand the language of their ancestors. Documents and recordings from the colonists are still understandable to modern characters (though some of the context has been lost). After being unburied, AIVAS is able to rapidly adjust its language to make itself understood. The dolphins underwent a similar linguistic shift, mostly becoming simpler and filled with abbreviations (for instance, the "blood fish" that attach themselves to the dolphins' undersides like leeches became "bluufis").
Executive Meddling: In a rare inversion of the typical trope, a studio executive actually stopped production of a TV series based on the novels a few days before shooting because of Adaptation Decay.
Fanwork Ban: The author was legendary for her adamant opposition to fanfic, and while she permitted roleplaying games, attempted to exercise editorial control over what could be done even in people's individual RPs. (The latter was less successful; even today, "pink dragons" are something of an in-joke in the fandom.)
Fantastic Recruitment Drive: When the dragonriders go on Search, they seek young men and women with latent telepathic abilities, able to bond with dragons.
Fate Worse Than Death: Most pernese consider being banished from a hold a harsher punishment than execution, since they automatically assume the condemned is going to be eaten by thread. Several characters learn to survive holdless simply by hiding in caves. Menolly notes that most of the time very little Thread actually gets to the surface thanks to the dragonriders.
Losing their bondmates is this for dragons/dragonriders. Riders whose dragons die usually commit suicide. Dragons whose riders die always commit suicide.
First Girl Wins: Robinton's short-lived wife Kasia still haunts his dreams. When he becomes involved with Silvina, he offers to marry her when she informs him that she's pregnant. She refuses (gently) because it's Kasia's name he still says in his sleep; he never recovers from losing her.
Jaxom and Sharra's relationship begins this way, after she treats him for Firehead Fever.
When Lessa is treating F'lar's knife wound, she can't help but notice his manliness.
Free-Love Future: The Weyr culture is highly liberated due to the nature of dragon/rider relationships; dragons mate with whom they choose and their partners are compelled to do the same. Children are fostered and raised by the Weyr as a whole to avoid attachments to any particular parent, given their high mortality rates.
Fun with Acronyms: Pern (Parallel Earth; Resources Negligible), and AIVAS (Artificial Intelligence Voice-Address System). Word Of God says that Pern is a backronym; McCaffrey came up with the name for the planet a long time before deciding it meant anything.
Gender Rarity Value: Applies in this case to the dragons; golds are the least common dragon color and yet the ones primarily responsible for populating the Weyrs. Over the last Long Interval, the Weyr population diminished to the point where there was only one gold alive at any time, making the extinction of the species a real possibility and justifying the taboo against flying golds in combat, something which had not existed in previous Passes.
Genetic Memory: There is a very strong implication that fire lizard memory is this; it's hard to imagine any other way that they could remember the events of Landing so vividly two thousand years later. In fact, it's fire lizard memory that leads Jaxom's team to discover the original Landing site, as well as AIVAS.
Another possibility that has been implied is that the telepathic firelizards form a weak hivemind, complete with a collective memory. However, the effect is functionally the same.
Gosh Dang It to Heck!: When not using Pern-specific curses, characters have a tendency to say things like "dratted" or "blasted." There's even "Jays" in Dragonsdawn, mean to be a Bowdlerization of "Jesus." Strangely, in the same book, one character calls another a "gobshite."
By contrast, there are quite a few "S-" and "F-bombs" in Dragonsdawn, what with the initial colonists still speaking (future) English.
Growing Up Sucks: For Piemur, puberty ends his sheltered life as a boy soprano. On the other hand, it also began his life as Robinton's secret apprentice, going to hatchings, smuggling queen fire lizard eggs, and... well, it stopped sucking pretty quickly.
Guile Hero: F'lar and Robinton, later Lessa. Also Sebell. It seems that this is one of the traits required to become MasterHarper. Menolly and Piemur to lesser degree.
Happily Married: A lot of Pernese couples don't actually marry, but among those who do, there are a number of happy couples. Petiron and Merelan fit this trope, as did Robinton and Kasia (for the few days of their marriage). Even these, who aren't officially married act like this anyway.
Hot For Teacher: It takes a while, but Menolly and Robinton finally acknowledge their UST in The White Dragon, although nothing comes of it. Her commitment to Sebell aside, Robinton had recently suffered a heart attack...
Huge Guy, Tiny Girl: F'lar and Lessa. Lessa is explicitly described as being little bigger than a child.
Hyperspace Is a Scary Place: Between, the dimension used by dragons and fire lizards when they teleport, is devoid of sensation, airless, and brutally cold.
And also apparently prone to causing miscarriages if a female rider is still in the early stages of pregnancy when she goes between.
I Thought Everyone Could Do That: Lessa talking to dragons, which gets F'lar extremely angry with her when he had been trying for years to figure out a way to coordinate all the dragons of a Weyr in combat.
I Have Your Wife:: How F’lar manages to convince the Holders to cooperate with Benden Weyr after the Long Interval — he sends dragons to abduct their wives and daughters.
Unusual mainly in that the hero (well, the heroine's Love Interest) is pulling this maneuver - and has justification. If the dragonriders starve, the entire colonized continent of Pern will either be eaten by Thread or starve in the midst of their dead land.
Well, the first one in a long time. It's been stated that before the pandemic in Moreta's time, which nearly wiped out humans on Pern, that there was far more sexual equality. After that, women reverted to more "traditional" roles because of the need to repopulate.
Jerk Ass: Okay, let's count 'em. Kylara, Lord Meron, Thella, T'kul, T'ron, Mardra, Merika, Masterglasssmith Norist (leader of the anti-AIVAS group), Lord Fax, Lord Chalkin, Yanus (Menolly's father), and more. It seems that every major antagonist character in the series is not merely opposed to the heroes but a complete dick as well.
Not just antagonists. F'lar in the first book is something of Jerkass Stu. Subsequent books rebalanced his personality considerably.
Mirrim's also a Jerk Ass, but while she's on the good guy side, everyone acknowledges that she's hard to get along with.
Kaleidoscope Eyes: Dragons' and fire lizards' eyes change color according to their mood.
Kill It with Fire: Dragons and fire lizards do indeed breathe fire, although it's the result of a hypergolic gas released when they chew a naturally occurring mineral named "firestone". On foot and in the queens' wing, Thread is fought with flamethrowers, or nitric acid sprayers (colloquially termed "agenothree" in the books — HNO3, get it?)
Knife Nut: Dragonriders don't carry swords, but many are deadly efficient duelists with eating knives.
Legend Fades to Myth: In Dragonsinger, we are introduced to the legend of Moreta, the Dragonlady who saved Pern from a deadly epidemic at the cost of her own life. Moreta: Dragonlady of Pern (published at a later date) recounts the actual events that gave rise to the legend.
Magical Abortion: The cold of between is sufficient to induce miscarriage and is deliberately used for this by female dragonriders, who are seldom able to take enough time off for pregnancy. It's either that, suffering accidental miscarriage from riding a dragon all the time, or fostering the kid out as soon as possible.
Medieval Stasis: For about two thousand years, Pern was medieval with very little structural/social change. Justified by the fact that most of the colonists' technology was lost or worn out after two hundred years, and the whole "Thread trying to eat everything organic" situation made them more concerned about surviving rather than technological advancement. When this incentive is removed after All the Weyrs of Pern, they begin to reclaim their lost technology with the help of the records and instruction provided by AIVAS.
Also justified because Pern was settled by Space Amish who wanted to get away from technology and develop a more agrarian society, though they didn't want to decay quite as far, hard or fast as they did.
Mercy Kill: Sometimes administered to badly injured Thread victims, by means of a lethal dose of "fellis", an herbal sedative.
Mr. Fanservice: Robinton, in-universe. In one scene Piemur is torn between amusement and frustration that his elderly mentor distracts all the ladies from him.
Never The Selves Shall Meet: This seems to change at different points in the series. At the start, Jaxom coming close to himself causes incredible exhaustion, and Lessa overrunning herself three times at the same temporal point results in swaying and mumbling gibberish. By the time of Todd McCaffrey's stories, M'hall and Master Harper Zist both talk to their past selves outright with no issue.
New Powers as the Plot Demands: In The Skies of Pern, the dragons "discover" their powers of telekinesis. This is not entirely pulled out of thin air; in All The Weyrs of Pern, AIVAS said that dragons should be able to do it, and it was covertly confirmed when the dragons were able to carry huge starship engine assemblies that, despite the lower gravity of the Red Star, they should not have been able to support, even en masse.
No Biochemical Barriers: Averted, as the Pernese settlers were armed with advance surveys and the science to clearly identify which local lifeforms were good to eat and which weren't, and they wouldn't have tried to settle Pern in the first place if the atmosphere wasn't breathable, etc. They also brought a lot of Earth lifeforms and conducted extensive experiments to determine compatibility, modifying genes where necessary — incidentally, this is why there are no bees or turkeys on Pern.
Or coffee. In Dragonsdawn it's mentioned that for some unknown reason coffee had proven unable to be adapted to growth on any planet other than Earth. On Pern, this leads to the development of a substitute made from the ground bark of a native tree, a drink that becomes known as klah.
No Blood Ties: Although bloodlines are acknowledged, it is common practice among Weyrfolk to foster their children to avoid maternal or paternal attachments; this lessens the trauma when riders are lost fighting Thread.
No Mere Windmill: Type B. When F'lar (and his father before him) warns the political leaders of the soon-to-begin Ninth Pass about the return of Thread, they refuse to believe him, until it starts dropping on their heads of course.
Outgrown Such Silly Superstitions: The Pernese colonists were specifically selected for their lack of susceptibility to religion. Throughout the entire series, God is not mentioned once. On the other hand, it's mentioned in Dragonsdawn that much of the Judeo-Christian Bible consists of plain common sense that the Pernese hold to "without any trace of fanatical devotion," and Aivas considers the Bible to be "the greatest book ever written by mankind."
Parental Abandonment: Lessa (parents murdered by Fax), Jaxom (mother died in childbirth, father was the aforementioned and unlamented Fax), and others.
Parental Incest: Stev Kimmer, in Rescue Run, has sex with his stepdaughters, and possibly his biological daughters.
Patronymic: Somewhat turned on its head. Many (though not all) Pernese children, particularly those born in the Weyrs, are given names which are meshes of the names of their father and mother. For example, F'lar's birth name was Fallarnon, after his father Falloner and mother Larna; his half-brother F'nor was Famanoran, after father Falloner and mother Manora. Sometimes other people's names are used in the convention, such as Menolly and Sebell's youngest son Robse (the first part of his name being in honor of Robinton).
Pride: Lessa, full stop. She is completely willing to let dragons battle with each other, because she feels insulted.
The Plague: The plot of Moreta and Nerilka's Story, as well as Dragonsblood.
Plot Hole: In the second part of Dragon's Fire, Moran decides to secretly follow Tenim after he abandons their group. Several chapters later, Moran is shown caring for the sick in a completely different location without any information as to how he got there.
P.O.V. Sequel: Moreta and Nerilka's Story. There's also a multitude of books that take place around the beginning of the Third Pass and near the middle of the Ninth that play with this; while they show many of the same events from different perspectives, they also have a tendency to cover time further back or forward than each other instead of taking place entirely simultaneously like a true P.O.V. Sequel.
Power Incontinence: Aramina leaves Benden Weyr because she can hear any and all dragons and can't shut them out.
Psychic Powers: It is said that all dragonriders are at least slightly telepathic to the extent required to communicate with their dragons. The dragons themselves, as well as their smaller cousins the fire lizards, are telepathic with each other and their riders. Lessa is a rare example of someone with the ability to affect other humans, but this was quietly downplayed as a plot point after being introduced.
All male Weyr riders have their names ritually contracted after Impression, to make shouted communication easier during Threadfall. For example, F'lar was born Fallarnon. Losing your dragon (and surviving) sometimes revokes this, as Lytol was L'tol when he was a rider, but went back to a non-hyphenated name (though not the same as his original name) after his dragon died.
Some humor comes from the difficulty in figuring out what Jaxom's rider name ought to be after he accidentally impresses Ruth; the situation is resolved by allowing him the unique privilege of being a dragonrider and Lord Holder.
Rape and Switch: Anne McCaffrey had an infamous opinion that anal rape releases hormones that turn men permanently gay; according to Word Of God this would canonically apply to male greenriders if one who wasn't already gay was chosen. This is never stated in the text, and as it makes very little sense to most people who are not Anne McCaffery, it's usually ignored.
As of Sky Dragons, it's been officially retconned.
Real Men Hate Affection: Petiron's attitude toward his son Robinton is a good example. Whether Petiron just didn't know how to show affection, or felt threatened by the fact that his son was much more talented than Petiron himself was, Robinton as a young boy is constantly looking for affection his father never offers. The situation improves as Robinton becomes an adult and is named MasterHarper, upon which Petiron steps down as MasterComposer and exiles himself to a minor holding to allow Robinton to become a leader in his own right. Later on, Petiron redeems himself when he discovers Menolly's talents (and sees her father's attempts to squelch her) and sends her to Robinton for mentoring.
F'Lar proves himself to one one of the wisest and influential men on Pern by his handling of crises in the first three books.
Robinton shows himself willing to listen to any issue within his Hall, punish those who break the rules regardless of rank or station, and admit to his own follies.
Harper Journeyman Rokayas of the Drum Heights was the only one who saw the shades of abuse Piemur was suffering but with no admittance from Piemur, his hands were tied. When Piemur fell down on greased steps, he got Piemur to help, and told Robinton and Menolly everything he suspected happened.
"The Reason You Suck" Speech: Robinton delivers three of these: to the Lord Holders in Dragonflight and Dragonquest, and to the Abominators in All The Weyrs of Pern.
Reassignment Backfire: A subversion occurs with Petiron, who was assigned to a backwater fishing Hold that just happened to beget one of the greatest musical prodigies in Pernese history, Menolly. Then it turns out that he was assigned at his own request, and that his son is the current Masterharper, Robinton.
Rebellious Princess: Nerilka, a Lord Holder's daughter, refuses to obey her Jerk Ass father's commands and becomes a nurse during the plague.
Retcon: A lot of plot elements got modified without comment between novels.
Some characters undergo spontaneous name changes between Dragonflight and Dragonquest: T'ton to T'ron, for example.
Lessa's Psychic Powers are explicit and quite strong in Dragonflight, with F'lar considering them unusual in their strength but hardly surprising. Later books downplay this to the point where it's almost ignored, leaving only the ability to talk to more than one's own dragon as a defined power.
At least, up until Dragonheart, when the Psychic Powers are said to be a skill possessed by strong-willed Weyrwomen as a side-effect of their bond with their dragon.
In Dragonquest, there's a specific reference to fire lizards "eating Thread". Granted that the person making the claim, Kylara, is mentally unstable and an unabashed liar, in later books the idea seems to be dropped in favor of fire lizards flaming thread like their larger cousins. There's also a mention in Dragonsinger, which parallels Dragonquest in the Harper Hall trilogy: Menolly's fire lizards, while shut inside the Harperhall refectory during Threadfall, get very excited and are described as making the motions of "licking Thread from the air."
Rocks Fall, Everyone Dies: Todd McCaffrey's books tend to end with the antagonist (and/or most of his cohorts) getting slaughtered.
Refusal Of The Call: Aramina is selected as a candidate for a queen dragon and considered guaranteed to Impress one. After Jayge rescues her from Thella, she refuses to go back. Jayge finds this unfathomable until she explains that she's incapable of tuning out the dragons' constant chatter.
Sapient Cetaceans: The original settlers brought intellectually enhanced dolphins with them, but lost contact in the exodus to the Northern Continent. In the aptly titled Dolphins of Pern, Jayge and Aramina's son Readis becomes the first to reestablish contact.
Science Fantasy: One of the classic unclassifiables. McCaffrey has always contended that her books are Science Fiction, not Fantasy. Her reasoning is that everything in the books is (in her estimation, at least), scientifically backed.
Science Is Bad: The Pern colony was founded on the principle of rejecting reliance on high technology to solve problems. Millennia later, this sentiment bestirs itself in the form of a violently Luddite group that attempts to sabotage anything related to AIVAS. AIVAS' discovery, however, is what eventually leads to the final end of Thread on Pern.
Science Marches On: Millennia in the future of our day, the world of Pern is finally saved with DOS. An AI version of DOS, but still...
Sci-Fi Writers Have No Sense of Scale: Distances seem to change at the plot's convenience, and either dragons in the Ninth Pass are ludicrously huge (bronzes and golds being much bigger than blue whales) or someone said "meters" when they meant "feet."
The year number got muddled when The White Dragon was published (15PP when it should really have been 13PP), and subsequent prequel books made this problem impossible to fix without messing up the chronology of the stories. The two main side-effects of this is that it means F'lessan somehow became a Candidate while two years underage, and Mirrim's Path took four years instead of two to become fully mature.
Character names - both major and minor - frequently end up changing between books. The worst example of this happening is probably that Lord Larad's wife's name strangely changes from Dulsay to Janissary in All the Weyrs of Pern and back to Dulsay again in The Skies of Pern.
In a few instances, a dead character has ended up appearing in a book that takes place after their death. Lord Oterel offers his support to young Readis in The Dolphins of Pern, despite a major part of the previous book dealing with people choosing his successor after his death.
Sex by Proxy: Thanks to the mental link between dragons and riders.
The Spymaster: MasterHarpers seem to be relatively benign examples. In addition to their teaching duties, almost all harpers sent abroad to teach also report on the general mood of the holds they're assigned to. In addition the Hall seems to produce one or two overly curious and quick-witted apprentices each generation. They eventually become one step below active spies, sent wherever their particular talents can be used and reporting directly to the MasterHarper. As of the Ninth Pass their chief agents seem to be Nip, Tuck/Traller, and Piemur.
Stable Time Loop: All time travel in series either results in one of these, or is the result of one of these.
Starving Artist: Iantine, in Dragonseye, is reduced to this on account of the bad weather and political corruption he encounters in Bitra.
A minor one in Dragonflight, where Lessa, Fax and F'lar are all intriguing over who has the right to rule Ruatha Hold. Lessa is the dispossessed rightful heir to Ruatha, Fax is the usurper, and F'lar unseats Fax, but in favor of Fax' son Jaxom rather than in Lessa's favor.
In the Harper Hall trilogy, Meron deliberately avoids naming a successor as he's dying (he wants a bloody succession fight to spite everyone,) until Robinton uses reverse psychology to get him to select the son he thinks nobody wants.
In All The Weyrs Of Pern, Oterel's death requires the other lords to vote on his successor. Thanks to petty political bickering, they have a lot of trouble getting consensus on the one son who isn't blatantly an idiot or wastrel.
Teacher/Student Romance: Robinton and Menolly, but an unusual example. They know they're fond of each other, and after his heart attack they both admit that said feelings are not 100% platonic. However, she's involved with someone else, and he is very much in favor of that relationship. So other than that brief recognition and pang, his relationship to her remains teacher / surrogate family.
Tele Frag: One of the risks of going between with a poorly visualized destination.
Teleporters and Transporters: Dragons and fire lizards are innate teleporters, and can bring passengers with them. This is accomplished by making use of Another Dimension, colloquially termed between, which lacks all sensation and is killingly cold. It is later discovered that they can teleport across interplanetary distances as well as through time, but the amount of time spent between increases with distance travelled (temporally and spacially). There's no oxygen between, which puts a very definite limit on hops through space and/or time.
Time Travel: An innate, if rarely used, ability of dragons and fire lizards. When travelling between, one must visualize one's destination accurately; apparently, this also includes time references. For example, if you visualize your destination in the morning, that's when you'll get there. It's even got a colloquial term in the story: "timing it".
Took a Level in Jerkass: Most notably with T'ton/T'ron and Mardra between Dragonflight and Dragonquest. Toric arguably qualifies as well.
Uncoffee: Klah, which is made from tree bark, started out as the colonists' ersatz coffee, and ended up filling the same cultural niche. It's explicitly stated to contain stimulants and taste exactly like hazelnut coffee. Dragonsdawn explains that coffee and tea plants can't flourish on Pernese soil, so the colonists looked elsewhere for their caffeine needs.
Unusual Euphemism: "Shards", "Shells", "Scorch it", and various other oaths are employed by Weyrfolk, mostly relating to dragons or Thread. Makes sense, as there's no religion on Pern, but respect for the dragonriders as saviors from Thread kind of fills a similar cultural role. "Fardling" is their variant of the "F" word. There's an index specifically for these in the early novels.
What Could Have Been: In The Masterharper of Pern Robinton is noted to have the ability to speak to (and hear) dragons, leading to his mother actually hoping that he would be Searched by a Weyr in order to get him out of their troubled home. Unfortunately no queens were laying when Robinton was of the optimal age to Impress a dragon.
Mardra abruptly vanishes halfway through The Renegades of Pern and is never mentioned again.
What Measure Is a Non-Cute?: Dragons? Gaze up in awe and go "whoa, cool!" Fire lizards? Gather round and Squee over the pretties. Watch-whers? Chained to a wall as barely tolerated "watchdogs". Although they are shown as capable of friendship and loyalty, and their distant kinship to dragons is mentioned from book one, it is not until the prequels that their origin is revealed — partially failed experiments in creating a second type of dragon.
Wild Card: Toric of Southern, in particular, seems to go back and forth between grudging ally and scheming antagonist. For the most part he's an over-ambitious control freak who, for various reasons, dislikes most of the series' protagonists and enjoys inconveniencing them, but doesn't really cross the line into actual villainy; he can even be occasionally helpful. In the later books, however, he becomes more and more obsessive and secretive, and his agenda more overtly sinister.
Writers Cannot Do Math: Several of the Ninth Pass books are a bit inconsistent with their events and what year they took place in. For example, The White Dragon is repeatedly said to take place five years after Dragonquest, yet the date given - 15PP - is actually seven years afterwards. In one particularly jarring example, Readis is said to be seven at the beginning of The Dolphins of Pern, despite the fact that his parents only met each other five years prior.