Pixar’s Finding Nemo earned its place as an animated classic thanks in large part to the depth of its characters. While the story of one adorable clownfish’s dangerous trek through the wild and his father’s persistent quest to recover him at any cost resonates on a human level, the diverse and well-sketched personalities of the surrounding cast are part of what brings the story to such vibrant life. From a trio of vegetarian sharks to a grumpy porcupine fish, Pixar’s story introduces a whole new generation to a variety of underwater species, and both play with and against our popular understanding of many aquatic creatures.
The sense that these animals interact with one another in a recognizable society breathes life into a simple story, but how much did Pixar get right? Here’s the real story behind five of the most important and unique fish species to star in Finding Nemo.
#1: Nemo and Marlin — Clownfish
Nemo and his father are both clownfish, and their personalities are respectably accurate to what they’re like in the wild. While Nemo may get the title billing, his father Marlin is the true protagonist characterized by his fatherly devotion.
Clownfish fathers take the primary role in nursing eggs — a job that involves keeping them clean and making sure they get the oxygen they need. This devotion in part comes from a hormone almost identical to oxytocin that could also have a role to play in both their less aggressive tendencies and generally monogamous natures. But while mild-mannered Marlin fits the profile for the clownfish, so does the bold and excitable personality of young Nemo.
A study of clownfish from two separate habitats found that one group operated together in a highly conformist manner with no sense of personality, while another was made up of varied individuals with behaviors that remained consistent and displayed a large amount of variance in terms of aggression, boldness, and sociability. The group of fish who had developed personalities occupied a habitat much safer and more protected than that of those who didn’t. That tracks closely with Nemo’s neighborhood and his home in particular. The tentacles of sea anemones are a popular choice of home for clownfish because clownfish secrete a mucous that negates their poison. Nemo’s house is a living creature engaged in mutual symbiosis. The anemone provides shelter and gets cleaned and fed in return.
#2: Dory — Blue Tang
The personable but hyperactive and memory-impaired blue tang became a Finding Nemo fan favorite and even earned her a starring role in her film. And as a blue tang, she plays an important role in maintaining coral ecosystems just like Nemo and Marlin do. As a generalized grazer, blue dories subsist entirely on algae and prevent these fast-growing protists from completely overgrowing the coral ecosystem. Like anemones, coral is an animal that also serves as a home for aquatic wildlife and is critical to the health of underwater ecosystems. Without blue tangs, many coral reefs would suffocate and die and imperil entire underwater communities.
Dory’s mind might not be the sharpest, but her spine certainly is. As one of the multiple species known as surgeonfish, blue tangs can use their razor-sharp spines to protect them against predators. And while Dory’s short-term memory is one of her most characteristic traits, it’s not something that most of her brothers and sisters share in the wild. There are no signs that blue tang has poor memories. It’s a characteristic that might have been adopted from the belief — itself an urban myth — that goldfish only have three-second memories.
The idea of Dory hanging out with other fish is more rooted in reality. Blue tangs are known to gather together in schools with other surgeonfish species, although you aren’t likely to find them mixing and mingling with clownfish.
#3: Gill — Moorish Idol
When Nemo is given a new home in a dentist’s aquarium, he finds himself taken under the fin of the gruff but ultimately kind tropical fish called Gill. Gill’s black, white, and yellow patterns identify him as a Moorish Idol — and while his insistent need to get out of the tank is in keeping with the personality of his species, it’s unlikely that he would have survived as long as he did.
Moorish Idols have very particular eating habits in captivity, and most will simply starve slowly rather than eat what’s presented to them. This could be a combination of serious anxiety and environmental conditions that have turned them into highly specialized feeders. Their long snouts are used to forage through crevices in coral and rock for small invertebrates, sponges, and algae.
Though they may be fragile and picky in captivity, Moorish idols like Gill have a habitat range that spans both sides of the Pacific Ocean as well as the Red Sea and the Indian Ocean. Moorish idols are diurnal fish, and the splash of yellow across their otherwise monochrome body is believed to be a way to confuse potential predators. When they retreat to the floor of the table coral environments they inhabit, their coloring adjusts to offer impressive camouflage against threats. Unfortunately, their visibility in daylight and the fact that they occupy relatively shallow waters make them easy prey for rare pet collectors.
#4: Bloat — Pufferfish
When Nemo’s friend Bloat explodes into a giant spiky ball in a fit of anger, it’s a great gag but also a generally accurate depiction of how the pufferfish acts in nature. Pufferfish employ this unusual talent as a defensive measure against predators. Their unique stomachs can expand outwards to inflate the fish up to three times its normal size. As if transforming into an enormous pincushion wasn’t enough of a deterrent, pufferfish. The porcupine pufferfish — the species to which Bloat belongs — secretes a toxin that’s over a thousand times more poisonous than cyanide. By any account, it’s an effective defense.
A bloat’s only true natural predator is sharks. Many species are immune to the pufferfish’s toxin, though tiger sharks are their most common threat in the wild. But despite carrying some of the deadliest weapons in the water, the average pufferfish is a significantly more shy creature than Bloat.
To some degree, Bloat was lucky that he ended up in the aquarium at a dentist’s office. The more likely alternative is the tank at a sushi restaurant. Pufferfish species are a delicacy in Japan and an expensive one at that. Without the knowledge and skill of an experienced sushi chef who can remove the liver and other parts laced with poison, pufferfish can be deadly.
#5: The Black Seadevil — Anglerfish
Dory’s encounter with a large and terrifying anglerfish may have only been brief, but it left an impression. And despite catching only a glimpse, we can discern quite a bit about it. The unique lure with a glowing tip that dangles from the anglerfish’s head tells us that it’s female. Males have no such lure and instead exist as parasites that latch onto the female and subsist off what she manages to catch with her luminous fishing rod.
While Dory would have made an enticing meal for this anglerfish, she would have been a rare one. Since these creatures lurk in the deepest and darkest trenches, their appetite is generally that of a bottom feeder: dead matter and waste that sunk from above, small invertebrates and crustaceans, and the occasional small fish. Despite that, female anglerfish can extend their jaw wide enough to consume creatures up to twice their size. In the rare instance where an anglerfish eats something as large as a squid or a sea turtle, it’s more luck than anything. Anglerfish are passive predators that settle for whatever meal comes to them, and their needle-like teeth are designed to trap prey so they can be swallowed whole rather than rip or tear at flesh.
We can’t know exactly what species inspired the crew at Pixar, but the anglerfish in Finding Nemo closely resembles the black seadevil. The species is rarely seen since its typical habitat is over a mile beneath sea level, where the pressure is enough to crush most creatures. The black seadevil was captured on camera for the first time in 2014 when one rose to depths of around 600 feet.