- For other uses, see Chan.
Two of the sexes, thaan and chan are approximately masculine, and the other two genders, zhen and shen, are approximately feminine. Andorians and Aenar accept the terms "male" and "female", and the pronouns "she/her" and "he/him", while dealing with binary-gendered species. (DS9 novel: Avatar)
In the primary Andorian language, known as Andorii, the distinctions are as follows:
- zhen - This sex roughly corresponds to female, and is the sex of the Andorian who will carry the zygote to term.
- shen - This sex also roughly corresponds to female and is where all Andorian life originates. Although the zhen carries the infant, the child begins as gametes from the shen.
- chan - This sex roughly corresponds to male.
- thaan - This sex also roughly corresponds to male.
The gametes of each "male" sex contain one quarter of the number of chromosomes necessary to produce offspring. During the conception of an Andorian child, the thaan fertilizes a shen's egg with his gamete. The chan then also fertilizes the egg. This produces a fertilized egg that develops into a zygote. The shen then transfers the zygote to the zhen's pouch, where it develops into an embryo. The Andorian fetus is incubated and nourished to term in the zhen's pouch. The zhen does not contribute genetically to offspring.
In some Andorian linguistic traditions, Andorians have name "prefixes" which indicate which of the four sexes (and/or genders) they are. The "prefixes" thus encountered are as follows.
- Zhen - zh' (eg. Shathrissia zh'Cheen, Charivretha zh'Thane)
- Shen - sh' (eg. Pava Ek'Noor sh'Aqabaa, Avaranthi sh'Rothress)
- Chan - ch' (eg. Thirishar ch'Thane, Thanashal ch'Shonnas)
- Thaan - th' (eg. Thelianaresth th'Vorothishria, Shelerib th'Zharath)
Polite form of addressEdit
Zha, Sha, Cha, Tha
zh'yi, sh'za, ch'te, th'se
zhavey, shreya, charan, thavan
zhei, shei, chei, thei
zhi, shi, chi, thi
Parent by marriageEdit
zhadi, shidei, chada, thadu
Child by marriageEdit
zhri'za, shri'za, chri'ze, thri'ze
The unique paradigm of the four Andorian and Aenar sexes have long caused reproductive problems on Andor. By the year 2155, the Andorian population was noticably dropping and the Aenar species numbered less than 5000. The Andorian thaan called Shran speculated that the Aenar were slowly going extinct. (ENT novel: The Good That Men Do)
By the year 2376, the Andorian species was also slowly dying out. The required union between all four sexes, and a shrinking window of fertility created a reproductive crisis to which there was no known solution.
While in the Gamma Quadrant, an Andorian chan, Starfleet ensign Thirishar ch'Thane, discovered a unique genetic turn key that existed in the non-viable eggs of a species known as the Yrythny. The eggs provided the solution to the Andorian's crisis by making it possible to widen the window of Andorian fertility and making it possible for a zhen to have more than one child at a time. (DS9 - Worlds of Deep Space Nine novel: Andor: Paradigm)
While the specific date has not been mentioned, the Andorian's suffered a "horrific biological holocaust" in their recent history (Prior to 2155) in which severe chromosomal damage was inflicted on most zhavey, causing trisomy and hesomy problems for their offspring. As a result, the fertility window for Andorians shrank to a mere 5 years and conception became substantially more difficult.
Andorian scientists attempted to map every family member's genetic lineage in an attempt to identify genetic drift where mutations may have occured and correct them, but this approach has yielded limited success.
As a result in the failure to genetically engineer a solution to the problem faced by the reproductive crisis, Andorian scientists started pairing bond groups to the most genetically compatible mates to ensure an increase success rate for conception. (DS9 novel: This Gray Spirit)
By 2381, it had been discovered that the Yrythny solution was not resolving the problems that the Andorians were facing. Many of the potential Andorian children were either miscarried or suffered serious genetic defects. The re-discovery of the Shedai meta-genome provided a potential solution to this issue. (ST - Typhon Pact novel: Paths of Disharmony)
By 2385, it was estimated that the Andorians would be largely extinct by the 25th century if a cure was not found. As a result, a Federation team of doctors lead by Julian Bashir discovered the cure for the reproductive issues while illegally utilizing the classified Shedai Meta-Genome data and disseminated it across Andor (with the assistance of the USS Aventine), despite the risk to the careers of all involved.
- Disclaimer: The writers and editors at Pocket Books extrapolated the four Andorian sexes from Data's line in the TNG episode: "Data's Day" that Andorians marry in groups of four. They freely admit that one does not necessarily equate to the other, but felt that this interpretation afforded the best storytelling opportunities. For an alternate view of Andorian reproduction, see the TNG novel: The Eyes of the Beholders. Also partially contrary to the novels, the more recent and higher-canon Star Trek: Enterprise TV series portrays the Andorians as having two sexes, and very much the same sexual habits as humans, although no information directly contradicting the possibility of four sexes and the social relationships described in the novels is ever given. Star Trek: Enterprise novels such as The Good That Men Do have brought the television Andorians into line with those in novels. For example, Shran's full name in The Good That Men Do is Hravishran th'Zoarhi.