Distinctive sub-species of Homo sapiens, one of the first genetic variants of humanity created by the new science of genetic engineering in the first century AT (after Tranquility), and one which inevitably cast a dark shadow over the gengineering of Humans which remained for centuries afterwards. This variant (one of several illegal tweaks which emerged at that time) is not generally considered a new species of humanity, as there is no evidence that any Jihadi ever had offspring.
The Jihadi are believed to have been first created in the mid to late 1st Century AT (2035-2068 AD on the old Earth calendar), by rogue, disgraced (or just supremely mercenary or desperate for work) gengineers (popularly known as genehackers) hailing from various parts of the world. A loose consortium of fundamentalist Arab Muslim groups and militant theocratic regimes in the Middle East (a region of Earth) funded and directed this clandestine project.
Innumerable Muslim families and prospective parents (mostly poor and invariably almost never fully informed as to the full scope, nature, ramifications, and risks of what ey were getting into) were alternately cajoled, bribed, threatened, intimidated, brainwashed, or forced outright into having eir future offspring modified at the zygote stage so that the children would be, and develop into, Homo Jihadi. "Giving a child to Allah," was the most common euphemistic term for this. "Striking a blow at the Great Satan and/or Israel," were also frequently invoked.
As this was a clandestine (and ludicrously illegal) operation, no reliable figures are available for the number of experiments that were necessary to successfully produce the first Jihadi, or what the success rate was even after success was first achieved, or what the mortality rate or long-term health effects were for women who (willingly or unwillingly) participated in this project as either egg- or womb-donors. Presumably, if known, these figures would serve only to damn this project further.
Homo Jihadi are distinguished from Homo Sapiens primarily by a heavily-modified endocrine system, which secretes large amounts of organic explosive (most often Penthyle, though other explosives of varying strength and stability have been recorded with some reliability). This explosive is deposited and becomes concentrated in the Jihadi's skeleton and other calcium-containing tissues, with the unintended side effect that Jihadi were extremely prone to osteoporosis and other bone diseases (The Jihadi were an extremely crude effort, with essentially no regard for the subjects or product of the experiment by the creators beyond just producing a convenient "living bomb," thus suffered a wide range of genetic defects in addition to osteoporosis), and detonated usually by a primer implanted in a false tooth, initiated typically by the Jihadi either "clacking" or gnashing eir teeth very hard. Jihadi would often swallow large amounts of ball bearings and other small metal objects before going out on eir mission, to magnify the already-formidable destructive effect of eir detonating in an enclosed space surrounded by Humans on all sides. This practice was actually self-defeating in a way as the Jihadi would inevitably set off metal detectors, so was soon largely abandoned.
The bodies of Homo Jihadi (those few captured intact and studied, at least) normally begin secreting and storing-up chemical explosive in large quantities around the onset of puberty. Jihadi mature at about the same rate as unaltered Homo Sapiens (onset of puberty at around 12-14 Earth years, full physical maturity at around 18-20 Earth years), during which time ey undergo training/conditioning (old terms for meming) similar to what unaltered Human suicide bombers were subjected to - Fed an "official, approved" version of the conflict eir creators are involved in, and the history behind such, so that the Jihadi will cheerfully accept eir purpose and carry out eir mission without wavering ("It is your holy duty to fight and die for [insert name of relevant nationality, ethnicity, memeticity, or purported deity here], and slay the evil [insert name of purportedly demonic enemy here] - Detonate yourself in a shopping mall, or on a bus or aircraft, filled with the greatest possible number of the enemy's civilians, and you will be welcomed into Paradise by 70 beautiful virgins, created just for you, to service you through all eternity"). The memetic component of Homo Jihadi was, oddly enough, already in place for some time before gengineering was developed to the level necessary to create em.
Note: Though it wasn't strictly necessary, at least not for any known reason, as far as eir intended function was concerned, Homo Jihadi, those sent out on missions and captured at any rate, were overwhelmingly male. Presumably, eir creators never intended em to self-propagate (It is not known whether Homo Jihadi were interfertile with unaltered Homo Sapiens, or whether Jihadis' particular genemods were heritable - No experiments to this effect are known to have ever been conducted, either by the Jihadis' creators or by others), and each individual Jihadi was a direct product of zygote-stage genetic manipulation upon a previously unaltered Human embryo.
The first Jihadi to be used publicly is believed to have detonated emself in a Tel Aviv bus station in the middle of 85 AT (2053 AD on the old Earth calendar), killing five people and injuring approximately a dozen more. More followed over the next several decades, usually sporadic, lacking any consistent strategy or pattern, and usually involving only single Jihadi (At one point in 97 AT - 2065 AD - as many as 50 Jihadi are believed to have detonated emselves near-simultaneously all around New Delhi, India, killing hundreds of Hindus and injuring thousands more, at the height of that nation's 7th war with its neighbour Pakistan; The Jihadi and eir Human masters are believed to have coordinated the massive attack using DNI among emselves; A similar attack, involving approximately one dozen Jihadi in New York City, was foiled the following year, using explosive-sniffing Neo-Dogs DNI-linked to eir Human masters, as well as DNI eavesdropping and trank guns).
The only reliable method at the time of detecting a Jihadi before e self-detonated (besides fortuitously listening in on eir DNI conversations with eir fellows or Human controllers), was using bomb- or chemical-sniffing animals (usually dogs, or the semi-sentient gene-tweaked Neo-Dogs, fortuitously developed in the United States a short time after Jihadi were first introduced). The only safe way to stop em from self-detonating (or detonating inadvertently if shot or struck with great force), is to use a fast tranquilizer delivered by a painless needle or some other method the subject is not aware of. Jihadi, ironically, inspired the more widespread adoption and use of non-lethal methods and equipment by police forces worldwide. This, and the ultimate wholesale renunciation and repudiation by the worldwide Muslim community of the Jihadi and eir creators, and increased international restrictions upon gengineering in general and Human gengineering in particular, were the only lasting effects the Jihadi had on Terragen culture.
The last confirmed instance of a Jihadi detonating emself occurred in 142 AT aboard an orbital habitat near Earth. No one, other than the Jihadi emself, was killed or injured, and the damage was quickly repaired. From the beginning, when the world first learned of em, those Jihadi which were taken alive (a rare event), were usually anaesthetized and painlessly terminated, and eir explosives neutralized and disposed of harmlessly. Eir creators were, of course, relentlessly persecuted around the world, and later nearby space, and generally suffered similar fates when caught. Jihadi are believed to have been totally extinct by 200 AT, eir genotype totally eradicated and all individual Jihadi, as well as eir creators and anyone remotely connected with em, either terminated, expiring naturally, or committing suicide under various circumstances - A dark chapter in the history of Human gengineering closed at last.