Documentary Sources of the Robotech Period

by Peter Walker (remove the 'NOSPAM-' for email), with Pieter Thomassen, Aubry Thonon, and Robert Morgenstern

The Invid Race

Invid Sensor Eye
Invid Egg
Invid Worker
Home Separator

This file is obsolete in that refers to events and dates from a timeline which we have since then overhauled.

It's priority for update is: low.

[Excerpted from the REF Officer's manual, Xenobiology section]

Very little is actually known about the Invid race itself. Posthumous examinations are always of limited utility, and our sole live informant, Tesla, captured during our initial liberation of Tirol, was inarguably less than forthright with his interviewers. Many gaps lie in our knowledge of this race, although some facts can be unambiguously determined.

Invid seem to come in two genders and a number of castes. In many cases, especially in the lower castes, gender was notoriously difficult to determine. Invid seem to have no primary or secondary sexual characteristics, and the genitalia of most Invid are superficially indistinguishable; the internal reproductive organs of the non-reproducing castes of the race are atrophied to the point where physical gender determination is almost impossible. However, even in the worst cases, there are sufficient similarities with the breeding castes to make a chromosomal determination of the gender, as the males are haploid (one of each pseudosome), and the females are diploid (a pair of each pseudosome).

This has profound effects upon the interrelationships between the genders. A male Invid receives two thirds of his genes from his mother, but only one third from his father. On the other hand, females receive equal fractions of their genes from each parent. Within siblings, a female shares only one third of her genes with her brothers, but three quarters of them with her sisters. Males only share one third of their genes with their brothers, but share two thirds of their genes with their sisters. This has led to the situation where male castes tend to be more closely involved with the care of their mother and her sterile female offspring, as they are equally related to each. Male Invid invest little care in their brothers or sons, especially those of sterile castes. Female siblings have the closest solidarity, owing to their genetic relationship, and are primary functionaries of the hive, especially with regards to their fertile sisters, to whom they are more closely related than even their own mother. This relationship might explain the sororal loyalty of those female Invid who chose to against from the Regess (as the sisters were more closely related to each other than to the Regess), and the ambivalence of the males (who were equally closely related to their sisters as to the Regess).

Contrary to some claims, all Invid have the same basic body morphology; that of a muscled humanoid with a snout-like head. Difference in caste (with the exception of the female reproducing castes) account for only modest variations, like height and body mass, and the presence of specialized features, such as the egg-bloated abdomen of the Sub-queen, or the hardened leathery skin and chitinous claws of the Warrior caste.

[Discussion of Invid physiology and anatomy deleted. For full details, see the REF Officer's Manual, pp 715-736]

At the lowest rung of Invid society seems to be the Warrior caste. Of the statistics we have been able to gather to date, this caste seems to be by far the most common of all Invid, though there are suggestions that this state of affairs is associated with the Invid's current plight. Specimens of both genders have been found among this group, though most are female. All are apparently sterile, and their reproductive organs are vestigial. Although no precise determination of intelligence has been possible for any caste of Invid relative to others or to humans, the brain mass to body mass ratio of this caste is the lowest (40% below that of the Worker), and much of the brain seems to be associated with motor and eye-hand skills. In addition, the endocrine system attached to the brain is more specialized, possibly indicating the prevalence of aggression-provoking and anti-fear hormones in this caste's body chemistry. The W! arriors are larger than many of their superiors (1.8 meters at full growth) and stronger as well. Most serve in lower-echelon combat capacities. The most common mecha for full-growth individuals in this caste is the Gurab Trooper. In addition, examinations of the corpses of Invid in Iigaa that were disabled while attempting to ram or claw another vessel reveals that all Invid kamikaze troopers are of the Warrior caste; in the case of the pilots of the Iigaa mecha, they appeared to be adolescent or juvenile Warriors, who had not yet reached full growth and could still fit in the more cramped cockpit. All indications are that this is the Invid's dedicated 'expendable' caste, dim-witted servants born and bred to die in the defense of the hive. Their metabolic rate seems to indicate a fairly short life-span, perhaps five years. While traces of chemicals found in the fruit of the Flower of Life are found in all Invid, the tissues of the Warrior caste Invid are extremely depleted of these, compared to other castes. It may be that Invid become Warriors when they are deprived in their early years of the fruit of the Flower of Life. This may have evolved as a reaction to stress on the hive's food supply, but little more is known.

Invid Worker

Faring much better in the hierarchy are the Workers. Though often slight in build, this caste of Invid appears to comprise the labor force of the Invid race. Their brain to body mass ratio is only slightly smaller than that of humans, and they appear to be fully sentient and intelligent. Workers are always sterile females, and their genital canal has been modified to form some sort of scent gland, the purposes of which are not entirely certain. As the Invid are telepathic, it is unlikely that these scents are used to communicate with their fellows in any important fashion. However, the scent glands do store a chemical remarkably similar in many essential ways to that produced in the scent-gland of the Pollinators Zor genetically engineered from the Cha-Cha, the domesticate of the Ci'vonian trahl, and a popular pet animal in the Empire. Considering the Invid's connection to the Flower of Life, it is likely that this pheromone is used to activate the Flower of Life's pistils, and make them receptive to pollination. If so, then Zor replicated the Invid protein and genetically spliced the DNA of the trahl to produce it in their scent gland, creating the Pollinator. If this is true, then the Pollinator is something of an artificial Worker-caste Invid, especially modified to pollinate the Flower of Life and help produce a fertile crop. Workers tend to be short (1.5m), but they can be found in both Iigaa light aerospace mecha and Gurab Trooper, and somewhat more rarely, the Hive Guard mecha, though as this caste is often seen in the role of battlefield commander, the Armed Iigaa and Gurab Shock Trooper appear to be preferred. They apparently never participate in the suicide attacks common to Warriors. It is possible, though uncertain, that Workers can be promoted to a fertile caste (adolescent Sub-queens have what appears to be a vestigial scent gland in their genital canal) by some biochemical means, but how this is done, and under which circumstances, is unknown. The lifespan of a Worker is unknown, but assuredly longer than that of the Warrior - perhaps two or three decades.

A greater mystery is the Drone caste. These relatively rare Invid are sterile males. They possess no scent glands, and so apparently are not associated with the Flower of Life in a direct fashion. This caste is rarely seen outside the hive, and then almost always in a Hive Guard suit. It is probable that the primary role of this caste is to serve the Sub-queen and tend to her eggs. It is possible, as with the Worker, that this caste can be promoted, in their case to a Sub-king, but this is rather uncertain. Drones are only marginally more robust than the Workers in size, and apparently live as long.

Regent & Tesla

Higher than the drones are the Sub-kings. There are apparently only a few sub-kings per hive, and possibly only one adult. This caste is comprised of fertile males. Although their role as breeders is clear, their duties inside the hive and out are not. They can be found in virtually any mecha (except the new Gosu Royal Command Battloid) leading large formations of Invid, and they can often be found inside the hive in no mecha at all. Tesla was definitely of this caste, and he was, by all accounts, an Invid Scientist. It may be possible that Sub-kings, and to a lesser extent, adolescent Sub-queens, are as diverse and individualized as one expects to find in humans. Sub-kings tend to be (at full growth) somewhat larger in height than Warriors, but many are rather corpulent. Sub-kings seem to live for centuries.

At the height of the Invid caste system are the Sub-queens. These are the breeding females, and from them all the Invid of the hive are born. As adolescents they serve as battlefield commanders, in a similar fashion to their Sub-king counterparts, but with higher rank and station. Once one is mated by a Sub-king, she retires to the hive, and her abdomen begins to bloat into an enormous egg-sack, rendering her immobile for life. Adult reproducing Sub-queens are invariably found under a dome in the hive's main incubation room. Eggs are apparently removed from the Sub-queen's shelter after they are laid, and are arranged in concentric circles around it and are tended by Drones, either the Sub-queen's own offspring, or if she is a new sub-queen, by that of her mother. The Sub-queen is reportedly a formidable telepath, and can call out for aid if threatened. This caste has the highest brain to body mass ratio of all normal Invid (at adolescence, of course - the ratio goes down as the sub-queen is impregnated. The brain mass increases, oddly enough, but the body mass' growth far outpaces it), but her intellectual and leadership role after she has been impregnated is unknown, as it appears that the Hive Brain is responsible for the more mundane functions of the hive. Sub-queens have long, but indeterminate lifespans - perhaps a century or more.

Invid Regent Invid Regess

Two more castes require mention. These are the Regent and the Regess. These appear to be a Sub-king and Sub-queen who have been promoted to levels of extreme authority and power; in the whole of the Invid race, there is apparently only one of each. The Regent was similar in appearance to a Sub-king, though he was much larger (3.8m) and had a cobra-like hood on his neck and several eyes along the spine. The Regess, by all reports, has taken a humanoid form since her encounter with Zor, and her appearance prior to that is only speculated. It is suspected that except in extraordinary circumstances, all Sub-queens and Sub-kings descend directly from the Regess and Regent. It may be that upon the demise of one, a new Regess and Regent are chosen from the Sub-queens and Sub-kings, and then the next generation of Invid descends from them. Current thinking is that the Regess and Regent are a relatively recent innovation in Invid society; before the unification of the Invid under these universal rulers an unknown number of millennia ago, the Sub-royalty were the summit of the hierarchy, and hives competed for food and territory. When the Regess and Regent appeared on the scene, the Invid race would have ceased to compete among themselves. The sketchy Tirolian records that survive indicate that at the time of first contact, the Invid were completely peaceful and prosperous, and the Warrior caste was extinct, a credit to the system of the Regency's overlordship of all hives and Sub-royalty. The lifespans of these supreme rulers of the race is unknown, but it is clear that the reigning Regess and Regent at the date of Tirol's occupation were the same ones that Zor visited nearly seven centuries ago.

[. . .]

It is entirely unclear if the Hive brain is even an Invid at all. While there are a number of genetic similarities with the Invid, there are many differences as well. It is entirely possible that the Hive brain is a completely artificial construct, based on the Invid's own DNA. The possibility that it is a 'promoted' Invid of some caste should not, however, be discounted.

[. . .]

The breeding Invid appear to have no particular concentration of nerve endings in their genitalia, and even the nerves that are there are not associated with what appear to be the Invid pleasure centers. It is entirely probable that the Invid derive no pleasure from copulation or physical intimacy. For all breeding females except perhaps the Regess, mating occurs only once per lifetime, so there is no need for sexuality. For their part, the lower castes seem to be completely asexual, with only the potential of being promoted into a mating caste of their chromosomal gender.

[. . .]

It would seem, from all reports, that the all of the early transmutant Invid (Solugi) on Earth are taken only from the Sub-queen and Sub-king caste. The reasons for this exclusivity to date are unknown.

[End of excerpt]

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Content by Peter Walker, with Aubry Thonon, Pieter Thomassen (remove the 'NOSPAM-' for email), and Rob Morgenstern
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Copyright © 1998, 1995 Robert Morgenstern, Pieter Thomassen, Peter Walker