History YMMV / SeaMonsters

* AluminiumChristmasTrees: No, the idea that ''Tanystropheus'' was capable of caudal autonomy (amputating its own tail like a modern lizard) was not invented by the show. That theory was actually proposed by German paleontologist Rupert Wild, a major figure in ''Tanystropheus'' research during the 20th century, who considered the animal to be part of the lepidosauromorphs (closer to lizards than archosaurs) [[note]] Most 21st-century studies recovered it as an archosauromorph [[/note]], and in a 1973 paper, Wild even cited one specimen from Ticino as allegedly sporting an autotomized tail, with textures on the 14th vertebra supposedly showing evidence of fractures. However, [[https://www.researchgate.net/publication/287927868_A_new_specimen_of_Tanystropheus_Reptilia_Protorosauria_from_the_Middle_Triassic_of_Switzerland_and_the_ecology_of_the_genus subsequent studies have rejected Wild’s interpretation of the specimen]].

* StockFootageFailure: Like in ''Walking with Beasts'', a shot of a modern whale raising its tail over the surface is used in one scene. Unlike in ''Beasts'', you can see not just the fluke but also the dorsal fin of the modern whale, revealing that it has a much shorter tail than ''Basilosaurus''. In addition, you can tell the land in the background is not tropical a tropical floodplain at all, but a mountain ranger complete with snow on it.

* StockFootageFailure: Like in ''Walking with Beasts'', a shot of a modern whale raising its tail over the surface is used in one scene. Unlike in ''Beasts'', you can see not just the fluke but also the dorsal fin of the modern whale, revealing that it has a much shorter tail than ''Basilosaurus''. In addition, you can tell the land in the background is not tropical at all, and so looks nothing alike.

** Although there is nothing to directly confirm it, most viewers think of ''Series/ChasedByDinosaurs'', this series and ''Series/PrehistoricPark'' as being in the same continuity [[note]]It’s heavily implied ''Chased by Dinosaurs'' at least do happens in the same continuity, as during the opening of ''Sea Monsters'' the narration mentions how Nigel had dangerous encounters with dinosaurs before and the Velociraptor, Giganotosaurus and Tarbosaurus of ''Chased by Dinosaurs'' do appear briefly in the intro.[[/note]].

** Although there is nothing to directly confirm it, most viewers think of ''Series/ChasedByDinosaurs'', this series and ''Series/PrehistoricPark'' as being in the same continuity.
* {{Narm}}: While on the whole the production values hold up very well for a straight to TV documentary from the early 2000s, every episode features Marven consulting a "time map" that looks like a long sheet of paper someone printed out about five minutes before shooting started. You can even see it curling up at the end. It really doesn't help that Marven keeps looking at it like it's some kind of profound document about to reveal the secrets of the cosmos to him.

* AluminiumChristmasTrees: No, the idea that ''Tanystropheus'' was capable of caudal autonomy (amputating its own tail like a modern lizard) was not invented by the show. That theory was actually proposed by German paleontologist Rupert Wild, a major figure in ''Tanystropheus'' research during the 20th century, who considered the animal to be part of lepidosauromorphs (closer to lizards than archosaurs) [[note]] Most 21st-century studies recovered it as an archosauromorph [[/note]], and in a 1975 paper, Wild even cited one specimen from Ticino as allegedly sporting an autotomized tail, with the break-off point being at the 14th caudal vertebra, with textures on the vertebrae supposedly supporting that. However, [[https://www.researchgate.net/publication/287927868_A_new_specimen_of_Tanystropheus_Reptilia_Protorosauria_from_the_Middle_Triassic_of_Switzerland_and_the_ecology_of_the_genus subsequent studies have rejected Wild’s interpretation of the specimen]].

* AluminiumChristmasTrees: No, the idea that ''Tanystropheus'' was capable of caudal autonomy (amputating its own tail like a modern lizard) was not invented by the show. That theory was actually proposed by German paleontologist Rupert Wild, a major figure in ''Tanystropheus'' research during the 20th century, who considered the animal to be part of lepidosauromorphs (closer to lizards than archosaurs) [[note]] Most 21st-century studies recovered it as an archosauromorph [[/note]], and in a 1975 paper, Wild even cited one specimen from Ticino as allegedly sporting an autotomized tail, with the break-off point being at the 14th caudal vertebra, with textures on the vertebrae supposedly supporting that. However, subsequent studies have all dismissed Wild’s interpretation of the specimen.

* AdaptationDisplacement: Not many are aware that ''Sea Monsters'' is technically it's own thing, due to it being widely available in the ''Chased by Dinosaurs'' DVD compilation released in 2004, wherein it was referred to as ''Chased By Sea Monsters''.

* NightmareFuel:
** The main theme is very dark and ominous, which fits as Nigel frequently goes into dark, murky waters almost entirely unprotected.
** The build-up to the Orthocone as the star attraction of the first segment is effective, and the revealing shot with ominous music is effective.
** The scene where the ''Cymbospondylus'' are circling Nigel and testing before attacking is appropriately tense.
** The ''Dunkleosteus'' is large, vicious, and eager to break open Nigel's diving cage. As Nigel puts it, he feels extremely vulnerable and it's strongly implied the cage would not have survived a prolonged attack. The cliffhanger of the first episode has a POVCam of Nigel as the ''Dunkleosteus'' barrels right towards him. When the action resumes in the next episode, there is a frightening "thunk" as it bangs into the cage, denting it like a can of soda. To top it all off, the ''Dunkleosteus'', when unable to eat Nigel, goes and eats a young member of its' own kind.
** The Eocene segment spends a lot of time building up the ''Basilosaurus'', with Nigel's crew using ominous whale calls to try to summon it to the ''Ancient Mariner''.
** The ''Megalodon'' segment also uses a lot of suspenseful build-up to the unveiling of the massive shark, and the cliffhanger of this episode ends when the ''Megalodon'' seemingly eats Nigel.
** In the Jurassic segment, the climax takes place at night when there's little light, and Nigel watches a swarm of ''Liopleurodon'' eating a dead ''Leedsicthys''. It's tense, alarming, and Nigel is only barely saved by his chemical deterrent. Even when the segment ends and Nigel begins leaving the sea, the narrator ominously warns that now he must face the deadliest sea of all time.
** The Cretaceous sea is dubbed "Hell's Aquarium", and is so dangerous that Nigel refuses to go into the water at first. Sure enough, he nearly pays the price when a ''Mosasaurus'' attacks his boat when he decides to go swimming with an ''Archelon'' anyway.
** The end of the show has one hell of a BolivianArmyEnding, in which the crew is asleep at night, only for the radar to begin ominously picking up a bogey, first one, then several, then ''an entire horde'' of ''Mosasaurus''. Considering the size of the biggest ones, it's safe to say they are more within the capability of taking down the ''Ancient Mariner'' and devouring her crew.

* AuthorsSavingThrow: ''Arsinoitherium'' is included here after its notable absence from ''Series/WalkingWithBeasts'''s "Whale Killer", which is also about ''Basilosaurus'' and set in the same location.

** The ''Dunkleosetus'' is large, vicious, and eager to break open Nigel's diving cage. As Nigel puts it, he feels extremely vulnerable and it's strongly implied the cage would not have survived a prolonged attack. The cliffhanger of the first episode has a POVCam of Nigel as the ''Dunkleosetus'' barrels right towards him. When the action resumes in the next episode, there is a frightening "thunk" as it bangs into the cage, denting it like a can of soda. To top it all off, the ''Dunkleosetus'', when unable to eat Nigel, goes and eats a young member of its' own kind.

* WhatMeasureIsANonBadass: So it is okay for a TV crew to kill an innocent fish just for a chance to attract a larger one?
** Meh, it's million of years in the past, the fish would've dies anyways.

* WhatAnIdiot: Nigel. Oh, Nigel. "There's no way I'd even think about jumping in waters where a ''mega-sized piranha'' is the least of your worries... OH!!! A TURTLE!!! WHERE'S MY DIVING SUIT?!"

* StockFootageFailure: Like in ''Walking with Beasts'', a shot of a modern whale raising its tail over the surface is used in one scene. Unlike in ''Beasts'', you can see not just the fluke but also the dorsal fin of the modern whale, revealing that it has a much shorter tail than ''Basilosaurus''.

* SignatureScene: Nigel nearly getting eaten by the Megalodon.

* {{Fanon}}: The unnamed whale hunted by the Megalodon is never identified in the franchise, but fans have basically agreed that it is ''Cetotherium''.