There are a lot of different species of organisms in the world.
And a lot of them happen to look and behave very similarly to each other. Unfortunately, Hollywood thinks that any person who is sufficiently intelligent is also able to name any animal or plant they come across with its specific (and correct) Latin name, taxonomic history, habitat, diet, and favorite color. In reality, unless you happen to be a foremost expert in studying that specific creature, it's unlikely that you could say anything more about it than "Hey, that's a bug!"
This is especially wrong when dealing with bacteria or other microscopic organisms since even though they may look similar at first glance, they could potentially belong to entirely different domains; aka, the highest-ranking taxon. And even microbes that are of the same species can look markedly different under different conditions.
With the advent of certain genetic techniques that allow scientists to specifically pin down what organism it is from analyzing its DNA, this is becoming somewhat more reasonable, however, but such techniques also take time and significant computing power.
In the same vein, this also applies when somebody sees a species' scientific name and can tell you the rest of its taxonomy from that information alone. This makes sense if they are familiar with the taxon, but otherwise, since the scientific name only gives genus and species, it sticks out as a serious research failure. Nor does knowing Latin tell you much from the pseudo-Latin names used in binomial nomenclature; Mephitis mephitis ("Stench stench") would probably be an animal renowned for its stink, but you wouldn't know that it's the striped skunk and not a polecat or stink beetle.
If this is only done with a single rare species, it can be viewed as just a rare bit of knowledge the person at hand happened to possess. Also, knowing your local flora and fauna often allows you to readily identify a plant or animal down to the subspecies, something that would be next to impossible if you did not know where the said plant or animal was collected. People who do a lot of hiking in a particular area would normally recognize the common species of plants and animals found in that area right away, regardless of any background in botany or biology.
Ultimately what classifies this as a Hollywood Science mistake is the assumption that ANYONE who is smart is able to identify a specific organism with uncanny accuracy by looking at a sample that is far too small or incomplete to normally reach that conclusion.
Sub-Trope of Artistic License – Biology. Contrast Small Taxonomy Pools, only well-known organisms, especially animals, show up in fiction. Compare Taxonomic Term Confusion, when a group of related organisms is referred to with a noun that seems generic, but actually has a specific use in biology.
Examples:
Anime & Manga
- Kaguya-sama: Love Is War: Both Kaguya and Fujiwara are able to correctly identify a lacquer tree cockroach from a quick glance. And then Karen ups the ante in the spin-off where she's able to do the same thing from a distance (though unlike the other two, her ability to do so is Played for Laughs).
Fan Works
- Paradoxus: In the second chapter, Galadwen refers to every human population she's ever met during her interdimensional travels as Homo sapiens even though she hasn't visited Earth's dimension yet nor she's the kind of character to bother studying human phylogenetics that much. Galadwen has a curious and even scientific disposition most of the time, however, she's also a Fantastic Racist biased against all non-elves and finds humans too brutish and violent for her interests. All in all, her qualifying all humans as hominids in the sapiens genre is more of a shortcut to showcase how, from her perspective, human beings are all the same.
- A.A. Pessimal's Discworld: Zoologist Johanna Smith-Rhodes can do this — up to a point. For a Rimwards Howondalandian, she's got the distinction between antelopes, gazelles, and deer wrong in one particular case and has also misidentified spider species, with interesting consequences. But everyone has an off day at her job every so often.
- Prehistoric Park: Returned from Extinction:
- The end-of-chapter notes tend to include the genus and species name of each creature rescued, something that is usually rather rare, even in the source material and other Prehistoric Park fanfiction. Some chapters include this simply for the sake of keeping things clear to the readers — the mission to rescue dinosaurs from Jurassic North America explicitly lists Big Al as an Allosaurus fragilus. That example, though, was also because all Allosaurus species from that time and location were rescued (for reference, North America has five different species of Allosaurus — A. fragilus, A. lucasi, A. jimmadseni, A. atrox, and A. amplus.
- Welcome To Prehistoric Kingdom downplays this in the first chapter by having Nigel only identify the non-sauropod dinosaurs in the region due to the sheer number of similarly sized sauropods from Cretaceous South America making it almost impossible to know the exact species.
- Col_Rutherford's "revised script"
of Indiana Jones and the Kingdom of the Crystal Skull changes Indy's line when he sees the carnivore ants from "Siafu!" to "Paraponera clavata!". According to the author, this is because siafu are from Africa, while the other are South American, where the film takes place. Now, as to why would an archaeologist know how to identify ants to species level, let alone from a distance...
Films — Live-Action
- The Beast: The resident scientist instantly identifies the squid as Archetuthis dux from a single sucker-claw and a whiff of ammonia. Especially egregious because Architeuthis, aka the giant squid, doesn't have claws. The colossal squid Mesonychoteuthis does, though. And most deep-sea squid have a lot of ammonia in their systems.
- In Like Flint: From microscopic traces, Derek Flint is able to identify the residue of exotic flowers and herbs (styrax, ylang, mimosa, hyacinth, cannabis, and Macedonian Brawley).
- Jurassic Park (1993): Grant is able to perfectly describe the exact hunting methods used by raptors, despite only having their bones to work with. And then there's them knowing that Rexy hunts by motion...
- The Lost World: The explorers are able to identify the dinosaurs to the precise genus all while looking at them from a distance, despite them only having seen dino skeletons so they should not know precisely what the real versions would look like—especially considering the millions of years of evolution in the interval, as well as the fact that only a handful of dinos had been discovered back then anyway. (To say nothing of feathers.)
- Them!: Dr. Medford identifies the exact species of a dead giant ant with a glance at the body, despite the fact that size is high on the list of characteristics used to identify ant species.
Literature
- The Armies of Daylight (by Barbara Hambly): Rudy can instantly identify a small animal from its bones, but he was highly trained in botany/zoology/magic and the question is: 'rabbit or chicken'.
- Dinoverse: Known dinosaur-nerd Betram probably has a reasonable chance of identifying common animals and plants in his favorite part of the Mesozoic. When it's his teacher's turn, well, Mr. London knew about Betram's adventure and regeared all his classes to be about the age of the dinosaurs, so he and his students aren't jumping into things blind, but it's weird how they quickly and unambigiously identify non-stock dinosaurs like Acrocanthosaurus and Hypsilophodon. And back in the first set of books Janine, who's insightful but not markedly interested in dinosaurs, happens to know about the digestive processes of Ankylosaurus.
- Jurassic Park (1990):
- While on the island, Grant identifies some dinosaur eggs he finds as those of Velociraptor. Quite a feat, as no one has ever found a Velociraptor egg fossil.note However, he uses educated guesses to identify the eggs, going by their size and the species known to be on the island.
- Sherlock Holmes: The title character correctly identifies the lion's mane jellyfish as the killer of the victim when he sees it at the bottom of a small pool. Very much justified, however, in that this is one very distinctive species (it's really, really big), that he'd spent a day reading up on it to confirm a vague memory, and that the victim's last words were "the lion's mane."
- The Silence of the Lambs: Identifying the species of an insect pupa found on the bodies of victims is a plot point, and the professional entomologist consulted needs time and equipment to answer the question.
- Jules Verne:
- Happens in many of his novels, where The Professor identifies and describes the characteristics of every plant or animal species the protagonists come across, as a means for Verne to show his work. Back then, however, that was what a lot of people read books for, since there was no other means of learning about them save by actually going to see them.
- 20,000 Leagues Under the Sea: The cake is taken by Conseil, a manservant to Prof. Arronax. He is a living classification handbook by virtue of having spent so long in scientific company. Amusingly, while Conseil has a remarkable memory for the taxonomic classification of species, he has very little idea of what they actually look like. By contrast, talented sailor and harpooner but rather Book Dumb Ned Land knows nothing much about taxonomy but can recognize many species of fish by sight. As Arronax remarks, by their powers combined they are one extremely talented marine biologist (even if Ned insists on classifying them solely by whether or not they're good to eat).
- Wings of Fire: Tamarin's very good at identifying flowers, even though she's blind. She somehow does it by smelling them. While smell does provide some indication of which flower is, several flowers have a similar enough aroma for this to be realistic.
Live-Action TV
- The Big Bang Theory: Subverted. Sheldon thinks he can identify the specific species of cricket by its chirping. He is in fact wrong, as pointed out by Howard (who spent his youth collecting insects), though Sheldon refuses to believe it. In the end, they turn to an associate with a PhD in entomology to settle the dispute... who identifies the cricket's species with a cursory glance, playing the trope straight. In fact, when asked, Professor Crawley claims he can identify every insect and arachnid in the world. There are 950,000 insect species and 50,000 arachnid species, making this claim rather unlikely. Even more so, arthropods are the single most diverse group on Earth; it is estimated that there are quite literally several million species of insects and arachnids that have not yet been identified, which would make it difficult to ID "any" one finds.
- Bones:
- A character identifies a fungus to species from a few hyphal traces. This is impossible even for trained mycologists as hyphae structure only gets you to the phylum level which is incredibly unspecific as it's just below the kingdom classification.
- A character whose specialty is in Art identifies a specific species of fungal spores thanks to having a boyfriend who studies them. That this is actually accepted in court is a major case of Hollywood Law.
- Hodgins, for which this trope essentially defines two-thirds of his job. The other third involves doing much the same, only with particulates. He is PhD-qualified for both of these, so it makes more sense than in many of these examples.
- Crossing Jordan: ANY time there are entomological traces found, ONE look was all Bug needs to tell what it was and how incredibly few but oh so conveniently dark and abandoned places it could be found.
- CSI: It typically justifies the insect portion of this as Grissom is an entomologist, but has been very guilty of this with regards to the flora.
- Monk: A rival detective is able to identify a mosquito's type and genus, as well as point out that it only appears in a specific spot in the city. Subverted when it is revealed that he was just making it up.
Video Games
- Jagged Alliance 2: Everyone has a comment on the monstrous and unearthly creatures you'll inevitably encounter if you tick the "Sci-Fi" option. Most mercenaries express various forms of surprise, but the medical doctors of your team will immediately start pinning down their taxonomy at first sight. (Crustacea, they seem to agree, which amusingly makes them Giant Enemy Crabs.)
Web Comics
- El Goonish Shive: The principal of Moperville South High School apparently knows the taxonomic family of squirrels. Despite the fact that that is easily recognized by biologists, the fact that he and several others recognize the word "Sciuridae" with presumably little biology experience is notable.
- Hitmen for Destiny: Professor Lostclock is able to name and describe the evolutionary history of more or less every animal in the multiverse.
- Particle Fiction: How can Ideasman figure out it's an Insecuritree so quickly? He gives a quick textbook description of the plant, which is printed in a more academic font.
Western Animation
- Droners: If a weird animal or plant appears, expect Enki to instantly identify it and start spurting facts about it.
- The Legend of Tarzan: Jane Porter is able to identify a (typically grossly inaccurate and quite oversized) velociraptor at a glance. Worse still is the fact that she isn't a paleontologist of any sort and in fact, the series takes place before velociraptors were scientifically described and named, and many decades before they were recognized in popular public consciousness.
