Humans are the dominant species of the Battle Angel Alita universe. They have colonized much of the Solar System and developed a variety of technological enhancements that have increased their capabilities. They have also mutated into different forms.
Cyberization is a key technological development which has given humans who have been cybernetically enhanced a wide variety and degree of capabilities, many in the realm of martial arts. For many however, particularly in the Scrapyard, cyberization is a necessary process in order to survive. The threshold definition of what it means to still be considered human despite becoming a full cyborg is retaining one's human brain.
Tiphareans are a product of eugenics, having been originally been created in order to endure the rigours and isolation of space travel. This was a carefully controlled and monitored process overseen by the Medical Inspection Bureau. However despite the rigid controls and purging of "defective" elements, the process effectively ended for the time being as a result of the Tipharean civil war in ES 591.
Methuselyzation is a process to halt human aging that was originally developed by the République Vénus, but has since become widespread through the Solar System after it was publicly leaked by Ping Wu in ES 386. Ironically a side effect of this has been a devaluation of human life, which has led to children being unwanted and considered less than human. It has also influenced the politics the of the Solar System, motivating Venus, the Jupiter System Union, and LADDER into conspiring to maintain the status quo at all costs.
Some humans mutated in the aftermath of the Geo Catastrophe in ES 55. While some degenerated to the point that they lost the power of speech, others grew to large sizes, but also mentally regressed.
Type-V mutants are notable mutants that have existed throughout human history. Popularly known as vampires, they lived within human society, operating in the background. Their numbers were decimated by the Geo Catastrophe and only one surviving Type-V mutant is left, Caerula Sanguis.
The Venusians are a notable form of human, having achieved this through their mastery of bioengineering. Used to tinkering with their bodies, they have bioengineered their physical forms into a variation known as the "Humpty-Dumpty" silhouette, which features a very large head, short, pudgy body, and near-residual, but functional arms and legs.
- Human on Wikipedia