Classification: Extra-terrestrial symbiotes

Location/Base of Operations: Unknown location in space;
    arrived on Earth around Lost Lake, in eastern Pennsylvania

Known Members: None named

Affiliations: Gideon Carruthers, Duff, an eel, a hawk, Sue Richards (Invisible Girl) - all served as hosts

First Appearance: Fantastic Four I#227 (February, 1981)

Powers/Abilities: The Brain Parasites are vaguely similar to trilobites (see comments), though they also possess facial features. They can apparently survive equally well on land or underwater.
    They are laid in eggs or pods containing five larvae. The Parasites could apparently reproduce when bonded to a female host (or possibly the host could be other sex, though it was only demonstrated on a single occasion). They are symbiotes, and must find a host to bond with within a short time of being hatched. They attach to a host (apparently it must be an animal, but mammals, reptiles, and birds are all acceptable) on the back of the neck, giving off a bright glow. They then apparently inject some sort enzyme or other chemical that apparently affects the brain, driving it back to a more primitive state. The chemical also affects the body of the host, reversing evolutionary changes and transforming it back into a more primitive and monstrous state. People are transformed back into a Neanderthal-like forms, eels into sea serpents, etc. These changes were not perfect de-evolution, but rather into a more monstrous form. In addition, the host also gained great strength and power, and could often fire brain blasts.
    Certain hosts, such as those mutated by cosmic radiation, prove partially resistant to the transformation and control of the hosts.
    The Brain Parasites apparently required oil or other fossil fuels. The hosts were driven to consume fuel, which apparently got into the bloodstream of the hosts so that the Parasites could consume it.

Height: 8 " long
Weight: 8 oz.


Traits: The Brain Parasites were driven to find a host as soon as possible, and the host was driven to consume fossil fuels. These directives overrode all else, and they were willing to combat others to achieve them.



(Fantastic Four I#227 (fb) - BTS) - Reed Richards postulated that the Brain Parasites are the dominant race on their native planet, which either exploded or was struck by a large meteor, which caused a large chunk of mineral, containing a pod of Brain Parasites, was liberated from their world and sent hurtling through space.

(Fantastic Four I#227) - The meteorite crashed on Earth, landing in Lost Lake. Its arrival was noted by Gideon Carruthers, an old friend of Reed Richards, who contacted Reed about it. Reed brought the FF and his son, Franklin, to the surrounding resort on vacation, but they soon found themselves under attack. One of the parasites bonded to a hawk that curiously investigated the large splash, transforming it into a large pteradon-like creature. It attacked the Fantastic Four as they flew towards the Lake, apparently trying to get at the Fantasticar's fuel. The creature exploded suddenly while they were fighting it, and Reed recovered the dead parasite. As Reed and Gideon studied the creature, another parasite bonded to a dog, Duff, transforming it a large wolf-like creature that assaulted a local gas station, injuring some police, and then consuming large amounts of oil from tanks it ripped open. As Ben fought the wolf-creature, Reed reached around and snagged the parasite from the back of its neck, briefly knocking the wolf creature out, until it turned back Duff, apparently no worse for wear.
    Reed was happy to study a live sample, but it was dead within an hour of separation from its host. In searching Lost Lake for more specimens, the FF were attacked by a giant, mutated eel, that also exploded while they fought it. Ben recovered the pod from the bottom of the ocean, but it was found to have five empty molds: unbeknownst to them, one of the parasites had crawled up under the back of Sue's hair and bonded to her.
    Searching for the last two parasites, Gideon Carruthers was mutated into monstrous form and sought the heating oil tank of a cabin, but the FF managed to stun him and tear the parasite from him. When Sue began to mutate, young Franklin made a cryptic confession that it was he who had been destroying the hosts. He hadn't been around when Duff or Gideon were mutated, and he likely wouldn't have wanted to hurt them anyway. Sue--still retaining some of her mind--appeared to be trying to get at the oil in the Fantasticar, but claimed to be serving some other purpose. Reed managed to get close enough to her to remove the parasite, which Franklin then destroyed.
    With the fifth parasite thus accounted for, the Fantastic Four headed out, completely unaware that Sue's parasite had spawned a new pod and five new larvae underneath the Fantasticar. As they took off, the F-car's jets scorched the pod, leaving the larvae dead...all save one...which weaved erratically toward the grass--to die fifteen feet away?...Or to find life, for another day?

Comments: Created by Doug Moench, Bill Sienkiewicz, & B. Patterson.

    Reed and the others mistakenly believed that the hosts were actually self-destructing, before they learned that Franklin was causing the explosions. This led to a further investigation of Franklin's powers...and Ego-Spawn.

    This is one of the first Fantastic Four stories I ever read, and I always liked it. In fact, the whole run by Moench is pretty entertaining.

    Parasites are technically entities that live off of others without giving anything back to the hosts, whereas symbiotes exist in a state of mutual benefit, each adding something to the other that promotes survival.

    Most of the origins and the physiology of the Brain Parasites are given by Reed, whose descriptions are a bit suspect. I'm not a neurologist, but I did study neurology back in school.
    He talks about the cortex at the base of the brain; the cortex is not at the base of the brain, but rather at the forebrain. It is actually a pair of structures, the cerebral hemispheres, that control higher function and intelligence, and make up the large, wrinkled section of the brain that you see in diagrams. This structure is smaller and smaller as you get into lesser animals--in rats there aren't even any wrinkles (gyri and sulci) in the cortex. I'm not certain if reptiles have a much of a cerebral cortex at all, but if so, it is very underdeveloped, which is why they don't have much capacity for emotion or problem solving. The cerebellum is the part of of the brain that coordinates fine movement (my one cat has cerebellar hypoplasia--this part of this brain is underdeveloped, due to a virus his mother had when she was pregnant with him. We call him Elvis, because his butt wiggles so much when he walks). The Medulla Oblongata is the most primitive part of the brain, just above the brainstem, and it primarily controls breathing and the cardiovascular system. When you read about people talking about the reptilian part of the brain, they are talking about the Medulla Oblongata, which is--I think (I haven't studied reptiles in about a decade)--the dominant portion of the brain in reptiles, as it is the most primitive section.

    Also, regarding Duff: The boy says, "he's just a mutt, but he's a real good dog."
A cannot recommend mutts strongly enough. I am a veterinarian, and I can tell you that if you want to make your vet rich, get a purebred. No offense to breeders, but it's a simple matter of genetics. The smaller the gene pool, the more you bring out recessive genetic traits, many of which are problems. Just like in-breeding in people (Deliverance? the British Royal family? <he says with tongue firmly in cheek>), you get lots of major defects from this sort of thing. Mutts tend to have the healthiest, strongest traits (IN GENERAL! THERE ARE ALWAYS EXCEPTIONS, BUT THESE ARE MAJORITY RULES). More often than not, you can get a free (or very cheap), healthy mutt from the pound, pay for its vaccines and yearly check-ups, and keep it until a ripe old age. Spend several hundred or more on a purebred, and look at it as foreshadowing as what you'll spend on the pet in the future.

Learn more about Trilobites:

No known connection to:

Gideon Carruthers has known connection to:

Dr. Gideon Carruthers

A geologist and old friend of Reed Richards, it was he who summoned Reed to Lost Lake to investigate the crashed meteorite. He assisted Reed's investigations, and was briefly mutated by one of the Brain Parasites, but was saved when Ben tore the parasite from his neck.

While possessed by the Brain Parasite, he took on the form of a monstrous primitive man, and had perhaps enhanced human to Class 10 strength and durability, and could fire mental stun blasts.

--Fantastic Four I#227





A pet of a family staying at the Lost Lake resort, he was briefly mutated by one of the Brain Parasites, but Reed and Ben managed to remove the parasite and cure him.

While possessed by the Brain Parasite, Duff took on the form of a monstrous wolf, and was very strong and savage, and could fire energy blasts from its head.

--Fantastic Four I#227






A resident of Lost Lake itself, it was mutated by one of the Brain Parasites and attacked the Fantastic Four as they searched for the source of the parasites. Franklin used his power to make it explode.

It was mutated into a giant sea-serpent-like creature. It was strong enough to restrain the Thing and to survive flame blasts from the Human Torch (though it did try to escape them).

--Fantastic Four I#227





A native of the Lost Lake resort, it was mutated by one of the Brain Parasites and attacked the Fantastic Four as they approached the resort. Franklin used his powers to make it explode.

It was mutated into a giant pteradon-like creature, powerful enough to shred steel in its talons.


--Fantastic Four I#227






Fantastic Four I#227, p7, pan4;
p15, pan1;
p15, pan3;
p27, pan8;
p26, pan7;
p24, pan5;
p14, pan7;
p12, pan7;
p18, pan1;
p5, pan1

Fantastic Four I#227 (February, 1981) - Doug Moench (writer), Bill Sienkiewicz (pencils), Bruce Patterson (inks), Jim Salicrup (editor)

Last updated: 01/18/04

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