Graboid - Physiology

Physiology

Graboids are depicted as subterranean animals, superficially resembling gigantic worms or grubs, with long, serpentine bodies. When fully grown, a graboid will measure up to 30 feet (9.1 m) long, and 6 feet (1.8 m) across at their widest point, and weigh 10-20 tons. Graboids completely lack eyes; they do not need them, due to living underground. Their heads consist of a massive, black, armored beak, which is used to push aside the dirt whilst digging. The beak opens up like a grotesque flower; it consists of a wide upper jaw, a thinner lower jaw, and a pair of hooked mandibles on either side. Whether they possess a skeleton or not is unknown, though a faux scientific document written by the SyFy channel hypotheses they have a semi-rigid internal structure, similar to the internal cuttlebone of cuttlefish.

Graboids have a trio of long, powerful, serpent-like tentacles, which are prehensile and have a reach of at least ten feet. Each of these tentacles (which have been loosely compared to functioning like the creature's tongue) terminates in a toothed mouth of its own. It is unclear if they actually bite off and swallow food on their own, or if they are simply used for getting a better grip on prey so it can be dragged into the gullet. Normally kept retracted in the graboid's throat, these tentacles were initially mistaken for the actual creatures, causing the characters in the first Tremors film to underestimate their underground opponents. The graboid's common name is derived from these prehensile tentacles, which "grab" prey and suck it back down the graboid's hungry gullet. At times, these tentacles appear to have minds of their own, hissing and writhing like snakes. Food is typically swallowed whole, though early in the original Tremors film, they are shown to dismember and decapitate their prey.

A graboid's hide is thick and leathery, with a rough, pebbly texture, giving them a reptilian appearance (though they are not reptiles). This makes them very hard to kill with anything short of saturation bombing or large-bore rounds. Graboids possess immense physical strength, able to topple over mobile homes, tow along an object heavy as a pickup truck without slowing down, smash through brick walls and pull an entire station wagon underground. Encircling their bodies are short spikes, which all move in unison to push the graboid through the dirt, similar to the setae on an earthworm. They are able to burrow faster than a human can run; a graboid in Tremors 3: Back to Perfection was able to keep pace with Burt's truck. With armored head and mobile spikes working together in unison, a graboid can "swim" through the loose soil at high speed like a shark in the water, though they are incapable of tunneling through solid rock. Graboids (and their imago forms, the shrieker and ass-blaster) have distinctive orange blood. Graboids also have a powerful stench, which is made evident on several occasions throughout the first film. Though underplayed in the 2nd and 3rd films, the graboid's stench becomes a critical plot point in Tremors 4; Juan is able to identify the graboids as being the unseen killers in the silver mines later in the film due to them sharing the same vile odor.