Graboid - Life Cycle

Life Cycle

• Graboids are hatched from eggs laid by ass-blasters (the final stage in the life cycle), as indicated in Tremors 3. These eggs split open diagonally. Carbon dating has shown that the eggs can lay dormant for at least 300 years, explaining why graboid sightings are rare and random. As shown in Tremors 4, the hatching of the eggs is prompted by warmth- in Tremors 4 hatched eggs were found in a hot spring.

• Baby graboids (nicknamed Dirt-Dragons, and by the fan-base, Shooters) are 4 feet (1.2 m) long and are much shorter and compact in comparison to the adults, but already have the typical set of jaws and mandibles. The baby graboids also have a row of armored scales on their backs for protection, which are shed before they fully mature.
• Like adults, they have large spikes used for digging; extra large rows of spikes sprout from the sides of their body. Being smaller than the adults, baby graboids are able to hurl themselves out of the dirt to tackle prey, like "some kind of demonic trout", according to Hiram Gummer. Their tentacles are underdeveloped at this point in their lifecycle.

• Upon maturing, graboids will resume attacking and consuming prey. After that, they will seek a secluded spot where they will metamorphose. Three to six shriekers will emerge from their body where they have been growing in large sacs, killing the graboid. The exact number of shriekers that emerge could possibly depend on how well-fed the graboid is.

• Upon emerging, shriekers will search for food. When having eaten a sufficient amount of food, shriekers will spit out a cocoon containing a mini version of themselves. This ability to reproduce asexually allows them to greatly expand their numbers over a short period of time, although it is unknown whether a shrieker can produce more than one clone. The newborn shrieker is fully developed, about 10 inches (25 cm) long and starts growing right after birth.

• When a shrieker is around 12 hours old, it will undergo a moulting process, turning into an ass-blaster. Ass-blasters can live up to several years (an individual sold to Siegfried and Roy in Tremors 3 was still alive two years later). They attack anything warm. While shriekers reproduce asexually when they have fed enough, ass-blasters, slip into a coma when they eat a large amount of food. They can reproduce, however – each ass-blaster carries a graboid egg in its gut. Because they cover large distances when flying, they can carry these eggs further away, as theorized by Jodi Chang in Tremors 3.